From 92b54aacc0de5446dd5497c39897b0bbff72e626 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Lo=C3=AFc=20Hoguin?= Date: Wed, 13 Jun 2018 09:54:12 +0200 Subject: Rebuild using Asciideck --- docs/en/cowboy/2.3/guide/constraints/index.html | 175 +-- docs/en/cowboy/2.3/guide/cookies/index.html | 171 ++- docs/en/cowboy/2.3/guide/erlang_web/index.html | 218 +--- docs/en/cowboy/2.3/guide/flow_diagram/index.html | 121 +- .../en/cowboy/2.3/guide/getting_started/index.html | 181 ++- docs/en/cowboy/2.3/guide/handlers/index.html | 106 +- docs/en/cowboy/2.3/guide/index.html | 211 +--- docs/en/cowboy/2.3/guide/introduction/index.html | 77 +- docs/en/cowboy/2.3/guide/listeners/index.html | 128 +-- docs/en/cowboy/2.3/guide/loop_handlers/index.html | 157 +-- docs/en/cowboy/2.3/guide/middlewares/index.html | 100 +- .../cowboy/2.3/guide/migrating_from_1.0/index.html | 480 ++------ .../cowboy/2.3/guide/migrating_from_2.0/index.html | 185 +-- .../cowboy/2.3/guide/migrating_from_2.1/index.html | 199 +--- .../cowboy/2.3/guide/migrating_from_2.2/index.html | 104 +- docs/en/cowboy/2.3/guide/modern_web/index.html | 131 +-- docs/en/cowboy/2.3/guide/multipart/index.html | 220 ++-- docs/en/cowboy/2.3/guide/req/index.html | 484 +++----- docs/en/cowboy/2.3/guide/req_body/index.html | 167 +-- .../en/cowboy/2.3/guide/resource_design/index.html | 245 +--- docs/en/cowboy/2.3/guide/resp/index.html | 476 +++----- .../en/cowboy/2.3/guide/rest_flowcharts/index.html | 284 +---- docs/en/cowboy/2.3/guide/rest_handlers/index.html | 413 +++---- .../en/cowboy/2.3/guide/rest_principles/index.html | 169 +-- docs/en/cowboy/2.3/guide/routing/index.html | 304 ++--- docs/en/cowboy/2.3/guide/specs/index.html | 1172 ++++++-------------- docs/en/cowboy/2.3/guide/static_files/index.html | 194 +--- docs/en/cowboy/2.3/guide/streams/index.html | 68 +- docs/en/cowboy/2.3/guide/ws_handlers/index.html | 371 +++---- docs/en/cowboy/2.3/guide/ws_protocol/index.html | 74 +- .../en/cowboy/2.3/manual/cowboy.set_env/index.html | 124 +-- .../2.3/manual/cowboy.start_clear/index.html | 159 +-- .../cowboy/2.3/manual/cowboy.start_tls/index.html | 165 +-- .../2.3/manual/cowboy.stop_listener/index.html | 87 +- docs/en/cowboy/2.3/manual/cowboy/index.html | 135 +-- docs/en/cowboy/2.3/manual/cowboy_app/index.html | 178 +-- .../2.3/manual/cowboy_constraints.int/index.html | 92 +- .../manual/cowboy_constraints.nonempty/index.html | 90 +- .../2.3/manual/cowboy_constraints/index.html | 85 +- .../2.3/manual/cowboy_handler.terminate/index.html | 115 +- .../en/cowboy/2.3/manual/cowboy_handler/index.html | 108 +- docs/en/cowboy/2.3/manual/cowboy_http/index.html | 321 ++---- docs/en/cowboy/2.3/manual/cowboy_http2/index.html | 139 +-- docs/en/cowboy/2.3/manual/cowboy_loop/index.html | 140 +-- .../cowboy/2.3/manual/cowboy_middleware/index.html | 123 +- .../2.3/manual/cowboy_req.binding/index.html | 122 +- .../2.3/manual/cowboy_req.bindings/index.html | 82 +- .../2.3/manual/cowboy_req.body_length/index.html | 86 +- .../cowboy/2.3/manual/cowboy_req.cert/index.html | 108 +- .../cowboy_req.delete_resp_header/index.html | 94 +- .../2.3/manual/cowboy_req.has_body/index.html | 76 +- .../2.3/manual/cowboy_req.has_resp_body/index.html | 83 +- .../manual/cowboy_req.has_resp_header/index.html | 95 +- .../cowboy/2.3/manual/cowboy_req.header/index.html | 129 +-- .../2.3/manual/cowboy_req.headers/index.html | 87 +- .../cowboy/2.3/manual/cowboy_req.host/index.html | 88 +- .../2.3/manual/cowboy_req.host_info/index.html | 84 +- .../cowboy/2.3/manual/cowboy_req.inform/index.html | 139 +-- .../2.3/manual/cowboy_req.match_cookies/index.html | 134 +-- .../2.3/manual/cowboy_req.match_qs/index.html | 134 +-- .../cowboy/2.3/manual/cowboy_req.method/index.html | 102 +- .../2.3/manual/cowboy_req.parse_cookies/index.html | 94 +- .../2.3/manual/cowboy_req.parse_header/index.html | 359 +++--- .../2.3/manual/cowboy_req.parse_qs/index.html | 118 +- .../cowboy/2.3/manual/cowboy_req.path/index.html | 87 +- .../2.3/manual/cowboy_req.path_info/index.html | 84 +- .../cowboy/2.3/manual/cowboy_req.peer/index.html | 97 +- .../cowboy/2.3/manual/cowboy_req.port/index.html | 88 +- .../cowboy/2.3/manual/cowboy_req.push/index.html | 162 +-- docs/en/cowboy/2.3/manual/cowboy_req.qs/index.html | 86 +- .../2.3/manual/cowboy_req.read_body/index.html | 165 +-- .../2.3/manual/cowboy_req.read_part/index.html | 200 ++-- .../manual/cowboy_req.read_part_body/index.html | 150 +-- .../cowboy_req.read_urlencoded_body/index.html | 140 +-- .../cowboy/2.3/manual/cowboy_req.reply/index.html | 190 +--- .../2.3/manual/cowboy_req.resp_header/index.html | 119 +- .../2.3/manual/cowboy_req.resp_headers/index.html | 75 +- .../cowboy/2.3/manual/cowboy_req.scheme/index.html | 93 +- .../2.3/manual/cowboy_req.set_resp_body/index.html | 151 +-- .../manual/cowboy_req.set_resp_cookie/index.html | 189 ++-- .../manual/cowboy_req.set_resp_header/index.html | 129 +-- .../manual/cowboy_req.set_resp_headers/index.html | 116 +- .../cowboy/2.3/manual/cowboy_req.sock/index.html | 83 +- .../2.3/manual/cowboy_req.stream_body/index.html | 129 +-- .../2.3/manual/cowboy_req.stream_reply/index.html | 174 +-- .../manual/cowboy_req.stream_trailers/index.html | 118 +- .../en/cowboy/2.3/manual/cowboy_req.uri/index.html | 199 ++-- .../2.3/manual/cowboy_req.version/index.html | 85 +- docs/en/cowboy/2.3/manual/cowboy_req/index.html | 556 +++------- docs/en/cowboy/2.3/manual/cowboy_rest/index.html | 845 ++++++-------- .../2.3/manual/cowboy_router.compile/index.html | 93 +- docs/en/cowboy/2.3/manual/cowboy_router/index.html | 117 +- docs/en/cowboy/2.3/manual/cowboy_static/index.html | 221 ++-- docs/en/cowboy/2.3/manual/cowboy_stream/index.html | 541 ++++----- .../cowboy/2.3/manual/cowboy_websocket/index.html | 370 ++---- .../cowboy/2.3/manual/http_status_codes/index.html | 267 +---- docs/en/cowboy/2.3/manual/index.html | 178 +-- 97 files changed, 5199 insertions(+), 12758 deletions(-) (limited to 'docs/en/cowboy/2.3') diff --git a/docs/en/cowboy/2.3/guide/constraints/index.html b/docs/en/cowboy/2.3/guide/constraints/index.html index 029dcc19..7907e2b5 100644 --- a/docs/en/cowboy/2.3/guide/constraints/index.html +++ b/docs/en/cowboy/2.3/guide/constraints/index.html @@ -62,141 +62,86 @@

Constraints

-

Constraints are validation and conversion functions applied -to user input.

-

They are used in various places in Cowboy, including the -router and the cowboy_req match functions.

-
+

Constraints are validation and conversion functions applied to user input.

+

They are used in various places in Cowboy, including the router and the cowboy_req match functions.

Syntax

-
-

Constraints are provided as a list of fields. For each field -in the list, specific constraints can be applied, as well as -a default value if the field is missing.

-

A field can take the form of an atom field, a tuple with -constraints {field, Constraints} or a tuple with constraints -and a default value {field, Constraints, Default}. -The field form indicates the field is mandatory.

-

Note that when used with the router, only the second form -makes sense, as it does not use the default and the field -is always defined.

-

Constraints for each field are provided as an ordered list -of atoms or funs to apply. Built-in constraints are provided -as atoms, while custom constraints are provided as funs.

-

When multiple constraints are provided, they are applied in -the order given. If the value has been modified by a constraint -then the next one receives the new value.

-

For example, the following constraints will first validate -and convert the field my_value to an integer, and then -check that the integer is positive:

-
-
-
PositiveFun = fun
-    (_, V) when V > 0 ->
-        {ok, V};
-    (_, _) ->
-        {error, not_positive}
-end,
-{my_value, [int, PositiveFun]}.
-

We ignore the first fun argument in this snippet. We shouldn’t. -We will simply learn what it is later in this chapter.

-

When there’s only one constraint, it can be provided directly -without wrapping it into a list:

-
-
-
{my_value, int}
-
-
-
+
{my_value, int}
+

Built-in constraints

-
-

Built-in constraints are specified as an atom:

-
- --- - - - - - - - - - +

Built-in constraints are specified as an atom:

+
Constraint Description

int

Converts binary value to integer.

+ + + + - - - + + - -
ConstraintDescription
intConverts binary value to integer.

nonempty

Ensures the binary value is non-empty.

nonemptyEnsures the binary value is non-empty.
-
-
- -
+

Custom constraints

-
-

Custom constraints are specified as a fun. This fun takes -two arguments. The first argument indicates the operation -to be performed, and the second is the value. What the -value is and what must be returned depends on the operation.

-

Cowboy currently defines three operations. The operation -used for validating and converting user input is the forward -operation.

-
-
-
int(forward, Value) ->
-    try
-        {ok, binary_to_integer(Value)}
-    catch _:_ ->
-        {error, not_an_integer}
-    end;
-

The value must be returned even if it is not converted -by the constraint.

-

The reverse operation does the opposite: it -takes a converted value and changes it back to what the -user input would have been.

-
-
-
int(reverse, Value) ->
-        try
-                {ok, integer_to_binary(Value)}
-        catch _:_ ->
-                {error, not_an_integer}
-        end;
-

Finally, the format_error operation takes an error -returned by any other operation and returns a formatted -human-readable error message.

-
-
-
int(format_error, {not_an_integer, Value}) ->
-        io_lib:format("The value ~p is not an integer.", [Value]).
-

Notice that for this case you get both the error and -the value that was given to the constraint that produced -this error.

-

Cowboy will not catch exceptions coming from constraint -functions. They should be written to not emit any exceptions.

-
-
+
int(format_error, {not_an_integer, Value}) ->
+	io_lib:format("The value ~p is not an integer.", [Value]).
+ +

Notice that for this case you get both the error and the value that was given to the constraint that produced this error.

+

Cowboy will not catch exceptions coming from constraint functions. They should be written to not emit any exceptions.

+ diff --git a/docs/en/cowboy/2.3/guide/cookies/index.html b/docs/en/cowboy/2.3/guide/cookies/index.html index 2f4c28f8..8d1e67bb 100644 --- a/docs/en/cowboy/2.3/guide/cookies/index.html +++ b/docs/en/cowboy/2.3/guide/cookies/index.html @@ -62,144 +62,103 @@

Using cookies

-

Cookies are a mechanism allowing applications to maintain -state on top of the stateless HTTP protocol.

-

Cookies are a name/value store where the names and values are -stored in plain text. They expire either after a delay -or when the browser closes. They can be configured on a -specific domain name or path, and restricted to secure -resources (sent or downloaded over HTTPS), or restricted -to the server (disallowing access from client-side scripts).

-

Cookie names are de facto case sensitive.

-

Cookies are stored client-side and sent with every subsequent -request that matches the domain and path for which they were -stored, until they expire. This can create a non-negligible -cost.

-

Cookies should not be considered secure. They are stored on -the user’s computer in plain text, and can be read by any -program. They can also be read by proxies when using clear -connections. Always validate the value before using it, -and never store any sensitive information inside it.

-

Cookies set by the server are only available in requests -following the client reception of the response containing -them.

-

Cookies may be sent repeatedly. This is often useful to -update the expiration time and avoid losing a cookie.

-
+

Cookies are a mechanism allowing applications to maintain state on top of the stateless HTTP protocol.

+

Cookies are a name/value store where the names and values are stored in plain text. They expire either after a delay or when the browser closes. They can be configured on a specific domain name or path, and restricted to secure resources (sent or downloaded over HTTPS), or restricted to the server (disallowing access from client-side scripts).

+

Cookie names are de facto case sensitive.

+

Cookies are stored client-side and sent with every subsequent request that matches the domain and path for which they were stored, until they expire. This can create a non-negligible cost.

+

Cookies should not be considered secure. They are stored on the user's computer in plain text, and can be read by any program. They can also be read by proxies when using clear connections. Always validate the value before using it, and never store any sensitive information inside it.

+

Cookies set by the server are only available in requests following the client reception of the response containing them.

+

Cookies may be sent repeatedly. This is often useful to update the expiration time and avoid losing a cookie.

Setting cookies

-
-

By default cookies are defined for the duration of the session:

-
-
-
SessionID = generate_session_id(),
-Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, Req0).
-

They can also be set for a duration in seconds:

-
-
-
SessionID = generate_session_id(),
-Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, Req0,
-    #{max_age => 3600}).
-

To delete cookies, set max_age to 0:

-
-
-
SessionID = generate_session_id(),
-Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, Req0,
-    #{max_age => 0}).
-

To restrict cookies to a specific domain and path, the options -of the same name can be used:

-
-
-
Req = cowboy_req:set_resp_cookie(<<"inaccount">>, <<"1">>, Req0,
-    #{domain => "my.example.org", path => "/account"}).
-

Cookies will be sent with requests to this domain and all -its subdomains, and to resources on this path or deeper -in the path hierarchy.

-

To restrict cookies to secure channels (typically resources -available over HTTPS):

-
-
-
SessionID = generate_session_id(),
-Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, Req0,
-    #{secure => true}).
-

To prevent client-side scripts from accessing a cookie:

-
-
-
SessionID = generate_session_id(),
-Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, Req0,
-    #{http_only => true}).
-

Cookies may also be set client-side, for example using -Javascript.

-
-
-
+
SessionID = generate_session_id(),
+Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, Req0,
+    #{http_only => true}).
+
+

Cookies may also be set client-side, for example using Javascript.

Reading cookies

-
-

The client only ever sends back the cookie name and value. -All other options that can be set are never sent back.

-

Cowboy provides two functions for reading cookies. Both -involve parsing the cookie header(s) and so should not -be called repeatedly.

-

You can get all cookies as a key/value list:

-
-
-
Cookies = cowboy_req:parse_cookies(Req),
-{_, Lang} = lists:keyfind(<<"lang">>, 1, Cookies).
-

Or you can perform a match against cookies and retrieve -only the ones you need, while at the same time doing -any required post processing using constraints. -This function returns a map:

-
-
-
#{id := ID, lang := Lang} = cowboy_req:match_cookies([id, lang], Req).
-

You can use constraints to validate the values while matching -them. The following snippet will crash if the id cookie is -not an integer number or if the lang cookie is empty. Additionally -the id cookie value will be converted to an integer term:

-
-
-
CookiesMap = cowboy_req:match_cookies([{id, int}, {lang, nonempty}], Req).
-

Note that if two cookies share the same name, then the map value -will be a list of the two cookie values.

-

A default value can be provided. The default will be used -if the lang cookie is not found. It will not be used if -the cookie is found but has an empty value:

-
-
-
#{lang := Lang} = cowboy_req:match_cookies([{lang, [], <<"en-US">>}], Req).
-

If no default is provided and the value is missing, an -exception is thrown.

-
- +
#{lang := Lang} = cowboy_req:match_cookies([{lang, [], <<"en-US">>}], Req).
+ +

If no default is provided and the value is missing, an exception is thrown.

+ diff --git a/docs/en/cowboy/2.3/guide/erlang_web/index.html b/docs/en/cowboy/2.3/guide/erlang_web/index.html index 97bc07d2..76a54644 100644 --- a/docs/en/cowboy/2.3/guide/erlang_web/index.html +++ b/docs/en/cowboy/2.3/guide/erlang_web/index.html @@ -62,194 +62,52 @@

Erlang and the Web

-

Erlang is the ideal platform for writing Web applications. -Its features are a perfect match for the requirements of -modern Web applications.

-
+

Erlang is the ideal platform for writing Web applications. Its features are a perfect match for the requirements of modern Web applications.

The Web is concurrent

-
-

When you access a website there is little concurrency -involved. A few connections are opened and requests -are sent through these connections. Then the web page -is displayed on your screen. Your browser will only -open up to 4 or 8 connections to the server, depending -on your settings. This isn’t much.

-

But think about it. You are not the only one accessing -the server at the same time. There can be hundreds, if -not thousands, if not millions of connections to the -same server at the same time.

-

Even today a lot of systems used in production haven’t -solved the C10K problem (ten thousand concurrent connections). -And the ones who did are trying hard to get to the next -step, C100K, and are pretty far from it.

-

Erlang meanwhile has no problem handling millions of -connections. At the time of writing there are application -servers written in Erlang that can handle more than two -million connections on a single server in a real production -application, with spare memory and CPU!

-

The Web is concurrent, and Erlang is a language designed -for concurrency, so it is a perfect match.

-

Of course, various platforms need to scale beyond a few -million connections. This is where Erlang’s built-in -distribution mechanisms come in. If one server isn’t -enough, add more! Erlang allows you to use the same code -for talking to local processes or to processes in other -parts of your cluster, which means you can scale very -quickly if the need arises.

-

The Web has large userbases, and the Erlang platform was -designed to work in a distributed setting, so it is a -perfect match.

-

Or is it? Surely you can find solutions to handle that many -concurrent connections with your favorite language… But all -these solutions will break down in the next few years. Why? -Firstly because servers don’t get any more powerful, they -instead get a lot more cores and memory. This is only useful -if your application can use them properly, and Erlang is -light-years away from anything else in that area. Secondly, -today your computer and your phone are online, tomorrow your -watch, goggles, bike, car, fridge and tons of other devices -will also connect to various applications on the Internet.

-

Only Erlang is prepared to deal with what’s coming.

-
-
-
+

When you access a website there is little concurrency involved. A few connections are opened and requests are sent through these connections. Then the web page is displayed on your screen. Your browser will only open up to 4 or 8 connections to the server, depending on your settings. This isn't much.

+

But think about it. You are not the only one accessing the server at the same time. There can be hundreds, if not thousands, if not millions of connections to the same server at the same time.

+

Even today a lot of systems used in production haven't solved the C10K problem (ten thousand concurrent connections). And the ones who did are trying hard to get to the next step, C100K, and are pretty far from it.

+

Erlang meanwhile has no problem handling millions of connections. At the time of writing there are application servers written in Erlang that can handle more than two million connections on a single server in a real production application, with spare memory and CPU!

+

The Web is concurrent, and Erlang is a language designed for concurrency, so it is a perfect match.

+

Of course, various platforms need to scale beyond a few million connections. This is where Erlang's built-in distribution mechanisms come in. If one server isn't enough, add more! Erlang allows you to use the same code for talking to local processes or to processes in other parts of your cluster, which means you can scale very quickly if the need arises.

+

The Web has large userbases, and the Erlang platform was designed to work in a distributed setting, so it is a perfect match.

+

Or is it? Surely you can find solutions to handle that many concurrent connections with your favorite language... But all these solutions will break down in the next few years. Why? Firstly because servers don't get any more powerful, they instead get a lot more cores and memory. This is only useful if your application can use them properly, and Erlang is light-years away from anything else in that area. Secondly, today your computer and your phone are online, tomorrow your watch, goggles, bike, car, fridge and tons of other devices will also connect to various applications on the Internet.

+

Only Erlang is prepared to deal with what's coming.

The Web is soft real time

-
-

What does soft real time mean, you ask? It means we want the -operations done as quickly as possible, and in the case of -web applications, it means we want the data propagated fast.

-

In comparison, hard real time has a similar meaning, but also -has a hard time constraint, for example an operation needs to -be done in under N milliseconds otherwise the system fails -entirely.

-

Users aren’t that needy yet, they just want to get access -to their content in a reasonable delay, and they want the -actions they make to register at most a few seconds after -they submitted them, otherwise they’ll start worrying about -whether it successfully went through.

-

The Web is soft real time because taking longer to perform an -operation would be seen as bad quality of service.

-

Erlang is a soft real time system. It will always run -processes fairly, a little at a time, switching to another -process after a while and preventing a single process to -steal resources from all others. This means that Erlang -can guarantee stable low latency of operations.

-

Erlang provides the guarantees that the soft real time Web -requires.

-
-
-
+

What does soft real time mean, you ask? It means we want the operations done as quickly as possible, and in the case of web applications, it means we want the data propagated fast.

+

In comparison, hard real time has a similar meaning, but also has a hard time constraint, for example an operation needs to be done in under N milliseconds otherwise the system fails entirely.

+

Users aren't that needy yet, they just want to get access to their content in a reasonable delay, and they want the actions they make to register at most a few seconds after they submitted them, otherwise they'll start worrying about whether it successfully went through.

+

The Web is soft real time because taking longer to perform an operation would be seen as bad quality of service.

+

Erlang is a soft real time system. It will always run processes fairly, a little at a time, switching to another process after a while and preventing a single process to steal resources from all others. This means that Erlang can guarantee stable low latency of operations.

+

Erlang provides the guarantees that the soft real time Web requires.

The Web is asynchronous

-
-

Long ago, the Web was synchronous because HTTP was synchronous. -You fired a request, and then waited for a response. Not anymore. -It all began when XmlHttpRequest started being used. It allowed -the client to perform asynchronous calls to the server.

-

Then Websocket appeared and allowed both the server and the client -to send data to the other endpoint completely asynchronously. The -data is contained within frames and no response is necessary.

-

Erlang processes work the same. They send each other data contained -within messages and then continue running without needing a response. -They tend to spend most of their time inactive, waiting for a new -message, and the Erlang VM happily activate them when one is received.

-

It is therefore quite easy to imagine Erlang being good at receiving -Websocket frames, which may come in at unpredictable times, pass the -data to the responsible processes which are always ready waiting for -new messages, and perform the operations required by only activating -the required parts of the system.

-

The more recent Web technologies, like Websocket of course, but also -HTTP/2.0, are all fully asynchronous protocols. The concept -of requests and responses is retained of course, but anything could -be sent in between, by both the client or the browser, and the -responses could also be received in a completely different order.

-

Erlang is by nature asynchronous and really good at it thanks to the -great engineering that has been done in the VM over the years. It’s -only natural that it’s so good at dealing with the asynchronous Web.

-
-
-
+

Long ago, the Web was synchronous because HTTP was synchronous. You fired a request, and then waited for a response. Not anymore. It all began when XmlHttpRequest started being used. It allowed the client to perform asynchronous calls to the server.

+

Then Websocket appeared and allowed both the server and the client to send data to the other endpoint completely asynchronously. The data is contained within frames and no response is necessary.

+

Erlang processes work the same. They send each other data contained within messages and then continue running without needing a response. They tend to spend most of their time inactive, waiting for a new message, and the Erlang VM happily activate them when one is received.

+

It is therefore quite easy to imagine Erlang being good at receiving Websocket frames, which may come in at unpredictable times, pass the data to the responsible processes which are always ready waiting for new messages, and perform the operations required by only activating the required parts of the system.

+

The more recent Web technologies, like Websocket of course, but also HTTP/2.0, are all fully asynchronous protocols. The concept of requests and responses is retained of course, but anything could be sent in between, by both the client or the browser, and the responses could also be received in a completely different order.

+

Erlang is by nature asynchronous and really good at it thanks to the great engineering that has been done in the VM over the years. It's only natural that it's so good at dealing with the asynchronous Web.

The Web is omnipresent

-
-

The Web has taken a very important part of our lives. We’re -connected at all times, when we’re on our phone, using our computer, -passing time using a tablet while in the bathroom… And this -isn’t going to slow down, every single device at home or on us -will be connected.

-

All these devices are always connected. And with the number of -alternatives to give you access to the content you seek, users -tend to not stick around when problems arise. Users today want -their applications to be always available and if it’s having -too many issues they just move on.

-

Despite this, when developers choose a product to use for building -web applications, their only concern seems to be "Is it fast?", -and they look around for synthetic benchmarks showing which one -is the fastest at sending "Hello world" with only a handful -concurrent connections. Web benchmarks haven’t been representative -of reality in a long time, and are drifting further away as -time goes on.

-

What developers should really ask themselves is "Can I service -all my users with no interruption?" and they’d find that they have -two choices. They can either hope for the best, or they can use -Erlang.

-

Erlang is built for fault tolerance. When writing code in any other -language, you have to check all the return values and act accordingly -to avoid any unforeseen issues. If you’re lucky, you won’t miss -anything important. When writing Erlang code, you can just check -the success condition and ignore all errors. If an error happens, -the Erlang process crashes and is then restarted by a special -process called a supervisor.

-

Erlang developers thus have no need to fear unhandled -errors, and can focus on handling only the errors that should -give some feedback to the user and let the system take care of -the rest. This also has the advantage of allowing them to write -a lot less code, and let them sleep at night.

-

Erlang’s fault tolerance oriented design is the first piece of -what makes it the best choice for the omnipresent, always available -Web.

-

The second piece is Erlang’s built-in distribution. Distribution -is a key part of building a fault tolerant system, because it -allows you to handle bigger failures, like a whole server going -down, or even a data center entirely.

-

Fault tolerance and distribution are important today, and will be -vital in the future of the Web. Erlang is ready.

-
-
-
+

The Web has taken a very important part of our lives. We're connected at all times, when we're on our phone, using our computer, passing time using a tablet while in the bathroom... And this isn't going to slow down, every single device at home or on us will be connected.

+

All these devices are always connected. And with the number of alternatives to give you access to the content you seek, users tend to not stick around when problems arise. Users today want their applications to be always available and if it's having too many issues they just move on.

+

Despite this, when developers choose a product to use for building web applications, their only concern seems to be "Is it fast?", and they look around for synthetic benchmarks showing which one is the fastest at sending "Hello world" with only a handful concurrent connections. Web benchmarks haven't been representative of reality in a long time, and are drifting further away as time goes on.

+

What developers should really ask themselves is "Can I service all my users with no interruption?" and they'd find that they have two choices. They can either hope for the best, or they can use Erlang.

+

Erlang is built for fault tolerance. When writing code in any other language, you have to check all the return values and act accordingly to avoid any unforeseen issues. If you're lucky, you won't miss anything important. When writing Erlang code, you can just check the success condition and ignore all errors. If an error happens, the Erlang process crashes and is then restarted by a special process called a supervisor.

+

Erlang developers thus have no need to fear unhandled errors, and can focus on handling only the errors that should give some feedback to the user and let the system take care of the rest. This also has the advantage of allowing them to write a lot less code, and let them sleep at night.

+

Erlang's fault tolerance oriented design is the first piece of what makes it the best choice for the omnipresent, always available Web.

+

The second piece is Erlang's built-in distribution. Distribution is a key part of building a fault tolerant system, because it allows you to handle bigger failures, like a whole server going down, or even a data center entirely.

+

Fault tolerance and distribution are important today, and will be vital in the future of the Web. Erlang is ready.

Learn Erlang

-
-

If you are new to Erlang, you may want to grab a book or -two to get started. Those are my recommendations as the -author of Cowboy.

-
+

If you are new to Erlang, you may want to grab a book or two to get started. Those are my recommendations as the author of Cowboy.

The Erlanger Playbook

-

The Erlanger Playbook is an ebook I am currently writing, -which covers a number of different topics from code to -documentation to testing Erlang applications. It also has -an Erlang section where it covers directly the building -blocks and patterns, rather than details like the syntax.

-

You can most likely read it as a complete beginner, but -you will need a companion book to make the most of it. -Buy it from the Nine Nines website.

-
-
+

The Erlanger Playbook is an ebook I am currently writing, which covers a number of different topics from code to documentation to testing Erlang applications. It also has an Erlang section where it covers directly the building blocks and patterns, rather than details like the syntax.

+

You can most likely read it as a complete beginner, but you will need a companion book to make the most of it. Buy it from the Nine Nines website.

Programming Erlang

-

This book is from one of the creator of Erlang, Joe -Armstrong. It provides a very good explanation of what -Erlang is and why it is so. It serves as a very good -introduction to the language and platform.

-

The book is Programming Erlang, -and it also features a chapter on Cowboy.

-
-
+

This book is from one of the creator of Erlang, Joe Armstrong. It provides a very good explanation of what Erlang is and why it is so. It serves as a very good introduction to the language and platform.

+

The book is Programming Erlang, and it also features a chapter on Cowboy.

Learn You Some Erlang for Great Good!

-

LYSE is a much more complete -book covering many aspects of Erlang, while also providing -stories and humor. Be warned: it’s pretty verbose. It comes -with a free online version and a more refined paper and -ebook version.

-
-
-
+

LYSE is a much more complete book covering many aspects of Erlang, while also providing stories and humor. Be warned: it's pretty verbose. It comes with a free online version and a more refined paper and ebook version.

+ diff --git a/docs/en/cowboy/2.3/guide/flow_diagram/index.html b/docs/en/cowboy/2.3/guide/flow_diagram/index.html index 05bc677a..d675a2f5 100644 --- a/docs/en/cowboy/2.3/guide/flow_diagram/index.html +++ b/docs/en/cowboy/2.3/guide/flow_diagram/index.html @@ -62,113 +62,30 @@

Flow diagram

-

Cowboy is a lightweight HTTP server with support for HTTP/1.1, -HTTP/2 and Websocket.

-

It is built on top of Ranch. Please see the Ranch guide for more -information about how the network connections are handled.

-
+

Cowboy is a lightweight HTTP server with support for HTTP/1.1, HTTP/2 and Websocket.

+

It is built on top of Ranch. Please see the Ranch guide for more information about how the network connections are handled.

Overview

-
-
-
-HTTP request/response flowchart -
-
-

As you can see on the diagram, the client -begins by connecting to the server. This step is handled -by a Ranch acceptor, which is a process dedicated to -accepting new connections.

-

After Ranch accepts a new connection, whether it is an -HTTP/1.1 or HTTP/2 connection, Cowboy starts receiving -requests and handling them.

-

In HTTP/1.1 all requests come sequentially. In HTTP/2 -the requests may arrive and be processed concurrently.

-

When a request comes in, Cowboy creates a stream, which -is a set of request/response and all the events associated -with them. The protocol code in Cowboy defers the handling -of these streams to stream handler modules. When you -configure Cowboy you may define one or more module that -will receive all events associated with a stream, including -the request, response, bodies, Erlang messages and more.

-

By default Cowboy comes configured with a stream handler -called cowboy_stream_h. This stream handler will create -a new process for every request coming in, and then -communicate with this process to read the body or send -a response back. The request process executes middlewares -which, by default, including the router and then the -execution of handlers. Like stream handlers, middlewares -may also be customized.

-

A response may be sent at almost any point in this -diagram. If the response must be sent before the stream -is initialized (because an error occurred early, for -example) then stream handlers receive a special event -indicating this error.

-
-
-
+HTTP request/response flowchart

As you can see on the diagram, the client begins by connecting to the server. This step is handled by a Ranch acceptor, which is a process dedicated to accepting new connections.

+

After Ranch accepts a new connection, whether it is an HTTP/1.1 or HTTP/2 connection, Cowboy starts receiving requests and handling them.

+

In HTTP/1.1 all requests come sequentially. In HTTP/2 the requests may arrive and be processed concurrently.

+

When a request comes in, Cowboy creates a stream, which is a set of request/response and all the events associated with them. The protocol code in Cowboy defers the handling of these streams to stream handler modules. When you configure Cowboy you may define one or more module that will receive all events associated with a stream, including the request, response, bodies, Erlang messages and more.

+

By default Cowboy comes configured with a stream handler called cowboy_stream_h. This stream handler will create a new process for every request coming in, and then communicate with this process to read the body or send a response back. The request process executes middlewares which, by default, including the router and then the execution of handlers. Like stream handlers, middlewares may also be customized.

+

A response may be sent at almost any point in this diagram. If the response must be sent before the stream is initialized (because an error occurred early, for example) then stream handlers receive a special event indicating this error.

Protocol-specific headers

-
-

Cowboy takes care of protocol-specific headers and prevents -you from sending them manually. For HTTP/1.1 this includes -the transfer-encoding and connection headers. For HTTP/2 -this includes the colon headers like :status.

-

Cowboy will also remove protocol-specific headers from -requests before passing them to stream handlers. Cowboy -tries to hide the implementation details of all protocols -as well as possible.

-
-
-
+

Cowboy takes care of protocol-specific headers and prevents you from sending them manually. For HTTP/1.1 this includes the transfer-encoding and connection headers. For HTTP/2 this includes the colon headers like :status.

+

Cowboy will also remove protocol-specific headers from requests before passing them to stream handlers. Cowboy tries to hide the implementation details of all protocols as well as possible.

Number of processes per connection

-
-

By default, Cowboy will use one process per connection, -plus one process per set of request/response (called a -stream, internally).

-

The reason it creates a new process for every request is due -to the requirements of HTTP/2 where requests are executed -concurrently and independently from the connection. The -frames from the different requests end up interleaved on -the single TCP connection.

-

The request processes are never reused. There is therefore -no need to perform any cleanup after the response has been -sent. The process will terminate and Erlang/OTP will reclaim -all memory at once.

-

Cowboy ultimately does not require more than one process -per connection. It is possible to interact with the connection -directly from a stream handler, a low level interface to Cowboy. -They are executed from within the connection process, and can -handle the incoming requests and send responses. This is however -not recommended in normal circumstances, as a stream handler -taking too long to execute could have a negative impact on -concurrent requests or the state of the connection itself.

-
-
-
+

By default, Cowboy will use one process per connection, plus one process per set of request/response (called a stream, internally).

+

The reason it creates a new process for every request is due to the requirements of HTTP/2 where requests are executed concurrently and independently from the connection. The frames from the different requests end up interleaved on the single TCP connection.

+

The request processes are never reused. There is therefore no need to perform any cleanup after the response has been sent. The process will terminate and Erlang/OTP will reclaim all memory at once.

+

Cowboy ultimately does not require more than one process per connection. It is possible to interact with the connection directly from a stream handler, a low level interface to Cowboy. They are executed from within the connection process, and can handle the incoming requests and send responses. This is however not recommended in normal circumstances, as a stream handler taking too long to execute could have a negative impact on concurrent requests or the state of the connection itself.

Date header

-
-

Because querying for the current date and time can be expensive, -Cowboy generates one Date header value every second, shares it -to all other processes, which then simply copy it in the response. -This allows compliance with HTTP/1.1 with no actual performance loss.

-
-
-
+

Because querying for the current date and time can be expensive, Cowboy generates one Date header value every second, shares it to all other processes, which then simply copy it in the response. This allows compliance with HTTP/1.1 with no actual performance loss.

Binaries

-
-

Cowboy makes extensive use of binaries.

-

Binaries are more efficient than lists for representing -strings because they take less memory space. Processing -performance can vary depending on the operation. Binaries -are known for generally getting a great boost if the code -is compiled natively. Please see the HiPE documentation -for more details.

-

Binaries may end up being shared between processes. This -can lead to some large memory usage when one process keeps -the binary data around forever without freeing it. If you -see some weird memory usage in your application, this might -be the cause.

-
-
+

Cowboy makes extensive use of binaries.

+

Binaries are more efficient than lists for representing strings because they take less memory space. Processing performance can vary depending on the operation. Binaries are known for generally getting a great boost if the code is compiled natively. Please see the HiPE documentation for more details.

+

Binaries may end up being shared between processes. This can lead to some large memory usage when one process keeps the binary data around forever without freeing it. If you see some weird memory usage in your application, this might be the cause.

+ diff --git a/docs/en/cowboy/2.3/guide/getting_started/index.html b/docs/en/cowboy/2.3/guide/getting_started/index.html index b06cbf46..d214b33a 100644 --- a/docs/en/cowboy/2.3/guide/getting_started/index.html +++ b/docs/en/cowboy/2.3/guide/getting_started/index.html @@ -62,161 +62,104 @@

Getting started

-

Erlang is more than a language, it is also an operating system -for your applications. Erlang developers rarely write standalone -modules, they write libraries or applications, and then bundle -those into what is called a release. A release contains the -Erlang VM plus all applications required to run the node, so -it can be pushed to production directly.

-

This chapter walks you through all the steps of setting up -Cowboy, writing your first application and generating your first -release. At the end of this chapter you should know everything -you need to push your first Cowboy application to production.

-
+

Erlang is more than a language, it is also an operating system for your applications. Erlang developers rarely write standalone modules, they write libraries or applications, and then bundle those into what is called a release. A release contains the Erlang VM plus all applications required to run the node, so it can be pushed to production directly.

+

This chapter walks you through all the steps of setting up Cowboy, writing your first application and generating your first release. At the end of this chapter you should know everything you need to push your first Cowboy application to production.

Prerequisites

-
-

We are going to use the Erlang.mk -build system. If you are using Windows, please check the -Installation instructions -to get your environment setup before you continue.

-
-
-
+

We are going to use the Erlang.mk build system. If you are using Windows, please check the Installation instructions to get your environment setup before you continue.

Bootstrap

-
-

First, let’s create the directory for our application.

-
-
$ mkdir hello_erlang
-$ cd hello_erlang
-

Then we need to download Erlang.mk. Either use the following -command or download it manually.

-
-
-
$ wget https://erlang.mk/erlang.mk
-

We can now bootstrap our application. Since we are going to generate -a release, we will also bootstrap it at the same time.

-
-
-
$ make -f erlang.mk bootstrap bootstrap-rel
-

This creates a Makefile, a base application, and the release files -necessary for creating the release. We can already build and start -this release.

-
-
$ make run
-...
-(hello_erlang@127.0.0.1)1>
-

Entering the command i(). will show the running processes, including -one called hello_erlang_sup. This is the supervisor for our -application.

-

The release currently does nothing. In the rest of this chapter we -will add Cowboy as a dependency and write a simple "Hello world!" -handler.

-
-
-
+... +(hello_erlang@127.0.0.1)1> +
+

Entering the command i(). will show the running processes, including one called hello_erlang_sup. This is the supervisor for our application.

+

The release currently does nothing. In the rest of this chapter we will add Cowboy as a dependency and write a simple "Hello world!" handler.

Cowboy setup

-
-

We will modify the Makefile to tell the build system it needs to -fetch and compile Cowboy:

-
-
-
PROJECT = hello_erlang
+
PROJECT = hello_erlang
 
-DEPS = cowboy
-dep_cowboy_commit = 2.3.0
+DEPS = cowboy
+dep_cowboy_commit = 2.3.0
 
-DEP_PLUGINS = cowboy
+DEP_PLUGINS = cowboy
 
-include erlang.mk
-

We also tell the build system to load the plugins Cowboy provides. -These include predefined templates that we will use soon.

-

If you do make run now, Cowboy will be included in the release -and started automatically. This is not enough however, as Cowboy -doesn’t do anything by default. We still need to tell Cowboy to -listen for connections.

-
- -
+include erlang.mk +
+

We also tell the build system to load the plugins Cowboy provides. These include predefined templates that we will use soon.

+

If you do make run now, Cowboy will be included in the release and started automatically. This is not enough however, as Cowboy doesn't do anything by default. We still need to tell Cowboy to listen for connections.

Listening for connections

-
-

First we define the routes that Cowboy will use to map requests -to handler modules, and then we start the listener. This is best -done at application startup.

-

Open the src/hello_erlang_app.erl file and add the necessary -code to the start/2 function to make it look like this:

-
-
-
start(_Type, _Args) ->
-    Dispatch = cowboy_router:compile([
-        {'_', [{"/", hello_handler, []}]}
+
start(_Type, _Args) ->
+    Dispatch = cowboy_router:compile([
+        {'_', [{"/", hello_handler, []}]}
     ]),
-    {ok, _} = cowboy:start_clear(my_http_listener,
-        [{port, 8080}],
-        #{env => #{dispatch => Dispatch}}
+    {ok, _} = cowboy:start_clear(my_http_listener,
+        [{port, 8080}],
+        #{env => #{dispatch => Dispatch}}
     ),
-    hello_erlang_sup:start_link().
-

Routes are explained in details in the Routing -chapter. For this tutorial we map the path / to the handler -module hello_handler. This module doesn’t exist yet.

-

Build and start the release, then open http://localhost:8080 -in your browser. You will get a 500 error because the module is missing. -Any other URL, like http://localhost:8080/test, will result in a -404 error.

-
- -
+ hello_erlang_sup:start_link(). +
+

Routes are explained in details in the Routing chapter. For this tutorial we map the path / to the handler module hello_handler. This module doesn't exist yet.

+

Build and start the release, then open http://localhost:8080 in your browser. You will get a 500 error because the module is missing. Any other URL, like http://localhost:8080/test, will result in a 404 error.

Handling requests

-
-

Cowboy features different kinds of handlers, including REST -and Websocket handlers. For this tutorial we will use a plain -HTTP handler.

-

Generate a handler from a template:

-
-
-
$ make new t=cowboy.http n=hello_handler
-

Then, open the src/hello_handler.erl file and modify -the init/2 function like this to send a reply.

-
-
-
init(Req0, State) ->
-    Req = cowboy_req:reply(200,
-        #{<<"content-type">> => <<"text/plain">>},
-        <<"Hello Erlang!">>,
-        Req0),
-    {ok, Req, State}.
-

What the above code does is send a 200 OK reply, with the -Content-type header set to text/plain and the response -body set to Hello Erlang!.

-

If you run the release and open http://localhost:8080 -in your browser, you should get a nice Hello Erlang! displayed!

-
- +
init(Req0, State) ->
+    Req = cowboy_req:reply(200,
+        #{<<"content-type">> => <<"text/plain">>},
+        <<"Hello Erlang!">>,
+        Req0),
+    {ok, Req, State}.
+ +

What the above code does is send a 200 OK reply, with the Content-type header set to text/plain and the response body set to Hello Erlang!.

+

If you run the release and open http://localhost:8080 in your browser, you should get a nice Hello Erlang! displayed!

+ diff --git a/docs/en/cowboy/2.3/guide/handlers/index.html b/docs/en/cowboy/2.3/guide/handlers/index.html index e8567d8e..61d83e67 100644 --- a/docs/en/cowboy/2.3/guide/handlers/index.html +++ b/docs/en/cowboy/2.3/guide/handlers/index.html @@ -62,91 +62,57 @@

Handlers

-

Handlers are Erlang modules that handle HTTP requests.

-
+

Handlers are Erlang modules that handle HTTP requests.

Plain HTTP handlers

-
-

The most basic handler in Cowboy implements the mandatory -init/2 callback, manipulates the request, optionally -sends a response and then returns.

-

This callback receives the Req object and the initial -state defined in the router configuration.

-

A handler that does nothing would look like this:

-
-
-
init(Req, State) ->
-    {ok, Req, State}.
-

Despite sending no reply, a 204 No Content response will be -sent to the client, as Cowboy makes sure that a response is -sent for every request.

-

We need to use the Req object to reply.

-
-
-
init(Req0, State) ->
-    Req = cowboy_req:reply(200, #{
-        <<"content-type">> => <<"text/plain">>
-    }, <<"Hello World!">>, Req0),
-    {ok, Req, State}.
-

Cowboy will immediately send a response when cowboy:reply/4 -is called.

-

We then return a 3-tuple. ok means that the handler ran -successfully. We also give the modified Req back to Cowboy.

-

The last value of the tuple is a state that will be used -in every subsequent callbacks to this handler. Plain HTTP -handlers only have one additional callback, the optional -and rarely used terminate/3.

-
-
-
+
init(Req0, State) ->
+    Req = cowboy_req:reply(200, #{
+        <<"content-type">> => <<"text/plain">>
+    }, <<"Hello World!">>, Req0),
+    {ok, Req, State}.
+
+

Cowboy will immediately send a response when cowboy:reply/4 is called.

+

We then return a 3-tuple. ok means that the handler ran successfully. We also give the modified Req back to Cowboy.

+

The last value of the tuple is a state that will be used in every subsequent callbacks to this handler. Plain HTTP handlers only have one additional callback, the optional and rarely used terminate/3.

Other handlers

-
-

The init/2 callback can also be used to inform Cowboy -that this is a different kind of handler and that Cowboy -should switch to it. To do this you simply need to return -the module name of the handler type you want to switch to.

-

Cowboy comes with three handler types you can switch to: -cowboy_rest, cowboy_websocket -and cowboy_loop. In addition to those you -can define your own handler types.

-

Switching is simple. Instead of returning ok, you simply -return the name of the handler type you want to use. The -following snippet switches to a Websocket handler:

-
-
-
init(Req, State) ->
-    {cowboy_websocket, Req, State}.
-
- -
+
init(Req, State) ->
+    {cowboy_websocket, Req, State}.
+

Cleaning up

-
-

All handler types provide the optional terminate/3 callback.

-
-
-
terminate(_Reason, _Req, _State) ->
-    ok.
-

This callback is strictly reserved for any required cleanup. -You cannot send a response from this function. There is no -other return value.

-

This callback is optional because it is rarely necessary. -Cleanup should be done in separate processes directly (by -monitoring the handler process to detect when it exits).

-

Cowboy does not reuse processes for different requests. The -process will terminate soon after this call returns.

-
- +
terminate(_Reason, _Req, _State) ->
+    ok.
+ +

This callback is strictly reserved for any required cleanup. You cannot send a response from this function. There is no other return value.

+

This callback is optional because it is rarely necessary. Cleanup should be done in separate processes directly (by monitoring the handler process to detect when it exits).

+

Cowboy does not reuse processes for different requests. The process will terminate soon after this call returns.

+ diff --git a/docs/en/cowboy/2.3/guide/index.html b/docs/en/cowboy/2.3/guide/index.html index 88267686..2aede748 100644 --- a/docs/en/cowboy/2.3/guide/index.html +++ b/docs/en/cowboy/2.3/guide/index.html @@ -62,214 +62,85 @@

Cowboy User Guide

-
+ +

Rationale

-
-
-
-
-
+

Introduction

-
-
-
-
-
+

Configuration

-
-
-
-
-
+

Handlers

-
-
-
-
-
+

Request and response

-
-
-
-
-
+

REST

-
-
-
-
-
+

Websocket

-
-
-
-
-
+

Advanced

-
-
-
-
-
+

Additional information

-
-
-
-
+ + diff --git a/docs/en/cowboy/2.3/guide/introduction/index.html b/docs/en/cowboy/2.3/guide/introduction/index.html index eaeaf485..3a0db4b4 100644 --- a/docs/en/cowboy/2.3/guide/introduction/index.html +++ b/docs/en/cowboy/2.3/guide/introduction/index.html @@ -62,79 +62,40 @@

Introduction

-

Cowboy is a small, fast and modern HTTP server for Erlang/OTP.

-

Cowboy aims to provide a complete modern Web stack. -This includes HTTP/1.1, HTTP/2, Websocket, Server-Sent Events and -Webmachine-based REST.

-

Cowboy comes with functions for introspection and tracing, enabling -developers to know precisely what is happening at any time. Its modular -design also easily enable developers to add instrumentation.

-

Cowboy is a high quality project. It has a small code base, is very -efficient (both in latency and memory use) and can easily be embedded -in another application.

-

Cowboy is clean Erlang code. It includes hundreds of tests and its code -is fully compliant with the Dialyzer. It is also well documented and -features a Function Reference, a User Guide and numerous Tutorials.

-
+

Cowboy is a small, fast and modern HTTP server for Erlang/OTP.

+

Cowboy aims to provide a complete modern Web stack. This includes HTTP/1.1, HTTP/2, Websocket, Server-Sent Events and Webmachine-based REST.

+

Cowboy comes with functions for introspection and tracing, enabling developers to know precisely what is happening at any time. Its modular design also easily enable developers to add instrumentation.

+

Cowboy is a high quality project. It has a small code base, is very efficient (both in latency and memory use) and can easily be embedded in another application.

+

Cowboy is clean Erlang code. It includes hundreds of tests and its code is fully compliant with the Dialyzer. It is also well documented and features a Function Reference, a User Guide and numerous Tutorials.

Prerequisites

-
-

Beginner Erlang knowledge is recommended for reading this guide.

-

Knowledge of the HTTP protocol is recommended but not required, as it -will be detailed throughout the guide.

-
-
-
+

Beginner Erlang knowledge is recommended for reading this guide.

+

Knowledge of the HTTP protocol is recommended but not required, as it will be detailed throughout the guide.

Supported platforms

-
-

Cowboy is tested and supported on Linux, FreeBSD, Windows and OSX.

-

Cowboy has been reported to work on other platforms, but we make no -guarantee that the experience will be safe and smooth. You are advised -to perform the necessary testing and security audits prior to deploying -on other platforms.

-

Cowboy is developed for Erlang/OTP 19.0 and newer.

-
-
-
+

Cowboy is tested and supported on Linux, FreeBSD, Windows and OSX.

+

Cowboy has been reported to work on other platforms, but we make no guarantee that the experience will be safe and smooth. You are advised to perform the necessary testing and security audits prior to deploying on other platforms.

+

Cowboy is developed for Erlang/OTP 19.0 and newer.

License

-
-

Cowboy uses the ISC License.

-
-
-
Copyright (c) 2011-2017, Loïc Hoguin <essen@ninenines.eu>
+
Cowboy uses the ISC License.

+
Copyright (c) 2011-2017, Loïc Hoguin <essen@ninenines.eu>
 
 Permission to use, copy, modify, and/or distribute this software for any
 purpose with or without fee is hereby granted, provided that the above
 copyright notice and this permission notice appear in all copies.
 
-THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
-OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

-

-
-
-
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

Versioning

-
-

Cowboy uses Semantic Versioning 2.0.0.

-
-
-
+

Cowboy uses Semantic Versioning 2.0.0.

Conventions

-
-

In the HTTP protocol, the method name is case sensitive. All standard -method names are uppercase.

-

Header names are case insensitive. When using HTTP/1.1, Cowboy converts -all the request header names to lowercase. HTTP/2 requires clients to -send them as lowercase. Any other header name is expected to be provided -lowercased, including when querying information about the request or -when sending responses.

-

The same applies to any other case insensitive value.

-
-
+

In the HTTP protocol, the method name is case sensitive. All standard method names are uppercase.

+

Header names are case insensitive. When using HTTP/1.1, Cowboy converts all the request header names to lowercase. HTTP/2 requires clients to send them as lowercase. Any other header name is expected to be provided lowercased, including when querying information about the request or when sending responses.

+

The same applies to any other case insensitive value.

+ diff --git a/docs/en/cowboy/2.3/guide/listeners/index.html b/docs/en/cowboy/2.3/guide/listeners/index.html index 0990f98c..743c25fb 100644 --- a/docs/en/cowboy/2.3/guide/listeners/index.html +++ b/docs/en/cowboy/2.3/guide/listeners/index.html @@ -62,109 +62,61 @@

Listeners

-

A listener is a set of processes that listens on a port for -new connections. Incoming connections get handled by Cowboy. -Depending on the connection handshake, one or another protocol -may be used.

-

This chapter is specific to Cowboy. Please refer to the -Ranch User Guide -for more information about listeners.

-

Cowboy provides two types of listeners: one listening for -clear TCP connections, and one listening for secure TLS -connections. Both of them support the HTTP/1.1 and HTTP/2 -protocols.

-
+

A listener is a set of processes that listens on a port for new connections. Incoming connections get handled by Cowboy. Depending on the connection handshake, one or another protocol may be used.

+

This chapter is specific to Cowboy. Please refer to the Ranch User Guide for more information about listeners.

+

Cowboy provides two types of listeners: one listening for clear TCP connections, and one listening for secure TLS connections. Both of them support the HTTP/1.1 and HTTP/2 protocols.

Clear TCP listener

-
-

The clear TCP listener will accept connections on the -given port. A typical HTTP server would listen on port 80. -Port 80 requires special permissions on most platforms -however so a common alternative is port 8080.

-

The following snippet starts listening for connections -on port 8080:

-
-
-
start(_Type, _Args) ->
-    Dispatch = cowboy_router:compile([
-        {'_', [{"/", hello_handler, []}]}
+
start(_Type, _Args) ->
+    Dispatch = cowboy_router:compile([
+        {'_', [{"/", hello_handler, []}]}
     ]),
-    {ok, _} = cowboy:start_clear(my_http_listener,
-        [{port, 8080}],
-        #{env => #{dispatch => Dispatch}}
+    {ok, _} = cowboy:start_clear(my_http_listener,
+        [{port, 8080}],
+        #{env => #{dispatch => Dispatch}}
     ),
-    hello_erlang_sup:start_link().
-

The Getting Started chapter uses a -clear TCP listener.

-

Clients connecting to Cowboy on the clear listener port are -expected to use either HTTP/1.1 or HTTP/2.

-

Cowboy supports both methods of initiating a clear -HTTP/2 connection: through the Upgrade mechanism -(RFC 7540 3.2) -or by sending the preface directly -(RFC 7540 3.4).

-

Compatibility with HTTP/1.0 is provided by Cowboy’s HTTP/1.1 -implementation.

-
-
-
+ hello_erlang_sup:start_link(). +
+

The Getting Started chapter uses a clear TCP listener.

+

Clients connecting to Cowboy on the clear listener port are expected to use either HTTP/1.1 or HTTP/2.

+

Cowboy supports both methods of initiating a clear HTTP/2 connection: through the Upgrade mechanism (RFC 7540 3.2) or by sending the preface directly (RFC 7540 3.4).

+

Compatibility with HTTP/1.0 is provided by Cowboy's HTTP/1.1 implementation.

Secure TLS listener

-
-

The secure TLS listener will accept connections on the -given port. A typical HTTPS server would listen on port 443. -Port 443 requires special permissions on most platforms -however so a common alternative is port 8443.

-

The function provided by Cowboy will ensure that the TLS -options given are following the HTTP/2 RFC with regards -to security. For example some TLS extensions or ciphers -may be disabled. This also applies to HTTP/1.1 connections -on this listener. If this is not desirable, Ranch can be -used directly to setup a custom listener.

-
-
+

The function provided by Cowboy will ensure that the TLS options given are following the HTTP/2 RFC with regards to security. For example some TLS extensions or ciphers may be disabled. This also applies to HTTP/1.1 connections on this listener. If this is not desirable, Ranch can be used directly to setup a custom listener.

+
-
start(_Type, _Args) ->
-    Dispatch = cowboy_router:compile([
-        {'_', [{"/", hello_handler, []}]}
+
start(_Type, _Args) ->
+    Dispatch = cowboy_router:compile([
+        {'_', [{"/", hello_handler, []}]}
     ]),
-    {ok, _} = cowboy:start_tls(my_http_listener,
+    {ok, _} = cowboy:start_tls(my_http_listener,
         [
-            {port, 8443},
-            {certfile, "/path/to/certfile"},
-            {keyfile, "/path/to/keyfile"}
+            {port, 8443},
+            {certfile, "/path/to/certfile"},
+            {keyfile, "/path/to/keyfile"}
         ],
-        #{env => #{dispatch => Dispatch}}
+        #{env => #{dispatch => Dispatch}}
     ),
-    hello_erlang_sup:start_link().
-

Clients connecting to Cowboy on the secure listener are -expected to use the ALPN TLS extension to indicate what -protocols they understand. Cowboy always prefers HTTP/2 -over HTTP/1.1 when both are supported. When neither are -supported by the client, or when the ALPN extension was -missing, Cowboy expects HTTP/1.1 to be used.

-

Cowboy also advertises HTTP/2 support through the older -NPN TLS extension for compatibility. Note however that -this support will likely not be enabled by default when -Cowboy 2.0 gets released.

-

Compatibility with HTTP/1.0 is provided by Cowboy’s HTTP/1.1 -implementation.

-
-
-
+ hello_erlang_sup:start_link(). +
+

Clients connecting to Cowboy on the secure listener are expected to use the ALPN TLS extension to indicate what protocols they understand. Cowboy always prefers HTTP/2 over HTTP/1.1 when both are supported. When neither are supported by the client, or when the ALPN extension was missing, Cowboy expects HTTP/1.1 to be used.

+

Cowboy also advertises HTTP/2 support through the older NPN TLS extension for compatibility. Note however that this support will likely not be enabled by default when Cowboy 2.0 gets released.

+

Compatibility with HTTP/1.0 is provided by Cowboy's HTTP/1.1 implementation.

Protocol configuration

-
-

The HTTP/1.1 and HTTP/2 protocols share the same semantics; -only their framing differs. The first is a text protocol and -the second a binary protocol.

-

Cowboy doesn’t separate the configuration for HTTP/1.1 and -HTTP/2. Everything goes into the same map. Many options are -shared.

-
- +

The HTTP/1.1 and HTTP/2 protocols share the same semantics; only their framing differs. The first is a text protocol and the second a binary protocol.

+

Cowboy doesn't separate the configuration for HTTP/1.1 and HTTP/2. Everything goes into the same map. Many options are shared.

+ + + diff --git a/docs/en/cowboy/2.3/guide/loop_handlers/index.html b/docs/en/cowboy/2.3/guide/loop_handlers/index.html index 57c5be92..637a54e1 100644 --- a/docs/en/cowboy/2.3/guide/loop_handlers/index.html +++ b/docs/en/cowboy/2.3/guide/loop_handlers/index.html @@ -62,131 +62,72 @@

Loop handlers

-

Loop handlers are a special kind of HTTP handlers used when the -response can not be sent right away. The handler enters instead -a receive loop waiting for the right message before it can send -a response.

-

Loop handlers are used for requests where a response might not -be immediately available, but where you would like to keep the -connection open for a while in case the response arrives. The -most known example of such practice is known as long polling.

-

Loop handlers can also be used for requests where a response is -partially available and you need to stream the response body -while the connection is open. The most known example of such -practice is server-sent events.

-

While the same can be accomplished using plain HTTP handlers, -it is recommended to use loop handlers because they are well-tested -and allow using built-in features like hibernation and timeouts.

-

Loop handlers essentially wait for one or more Erlang messages -and feed these messages to the info/3 callback. It also features -the init/2 and terminate/3 callbacks which work the same as -for plain HTTP handlers.

-
+

Loop handlers are a special kind of HTTP handlers used when the response can not be sent right away. The handler enters instead a receive loop waiting for the right message before it can send a response.

+

Loop handlers are used for requests where a response might not be immediately available, but where you would like to keep the connection open for a while in case the response arrives. The most known example of such practice is known as long polling.

+

Loop handlers can also be used for requests where a response is partially available and you need to stream the response body while the connection is open. The most known example of such practice is server-sent events.

+

While the same can be accomplished using plain HTTP handlers, it is recommended to use loop handlers because they are well-tested and allow using built-in features like hibernation and timeouts.

+

Loop handlers essentially wait for one or more Erlang messages and feed these messages to the info/3 callback. It also features the init/2 and terminate/3 callbacks which work the same as for plain HTTP handlers.

Initialization

-
-

The init/2 function must return a cowboy_loop tuple to enable -loop handler behavior. This tuple may optionally contain -a timeout value and/or the atom hibernate to make the -process enter hibernation until a message is received.

-

This snippet enables the loop handler:

-
-
-
init(Req, State) ->
-    {cowboy_loop, Req, State}.
-

This also makes the process hibernate:

-
-
-
init(Req, State) ->
-    {cowboy_loop, Req, State, hibernate}.
-
-
-
+
init(Req, State) ->
+    {cowboy_loop, Req, State, hibernate}.
+

Receive loop

-
-

Once initialized, Cowboy will wait for messages to arrive -in the process' mailbox. When a message arrives, Cowboy -calls the info/3 function with the message, the Req object -and the handler’s state.

-

The following snippet sends a reply when it receives a -reply message from another process, or waits for another -message otherwise.

-
-
-
info({reply, Body}, Req, State) ->
-    cowboy_req:reply(200, #{}, Body, Req),
-    {stop, Req, State};
-info(_Msg, Req, State) ->
-    {ok, Req, State, hibernate}.
-

Do note that the reply tuple here may be any message -and is simply an example.

-

This callback may perform any necessary operation including -sending all or parts of a reply, and will subsequently -return a tuple indicating if more messages are to be expected.

-

The callback may also choose to do nothing at all and just -skip the message received.

-

If a reply is sent, then the stop tuple should be returned. -This will instruct Cowboy to end the request.

-

Otherwise an ok tuple should be returned.

-
- -
+
info({reply, Body}, Req, State) ->
+    cowboy_req:reply(200, #{}, Body, Req),
+    {stop, Req, State};
+info(_Msg, Req, State) ->
+    {ok, Req, State, hibernate}.
+
+

Do note that the reply tuple here may be any message and is simply an example.

+

This callback may perform any necessary operation including sending all or parts of a reply, and will subsequently return a tuple indicating if more messages are to be expected.

+

The callback may also choose to do nothing at all and just skip the message received.

+

If a reply is sent, then the stop tuple should be returned. This will instruct Cowboy to end the request.

+

Otherwise an ok tuple should be returned.

Streaming loop

-
-

Another common case well suited for loop handlers is -streaming data received in the form of Erlang messages. -This can be done by initiating a chunked reply in the -init/2 callback and then using cowboy_req:chunk/2 -every time a message is received.

-

The following snippet does exactly that. As you can see -a chunk is sent every time an event message is received, -and the loop is stopped by sending an eof message.

-
-
-
init(Req, State) ->
-    Req2 = cowboy_req:stream_reply(200, Req),
-    {cowboy_loop, Req2, State}.
-
-info(eof, Req, State) ->
-    {stop, Req, State};
-info({event, Data}, Req, State) ->
-    cowboy_req:stream_body(Data, nofin, Req),
-    {ok, Req, State};
-info(_Msg, Req, State) ->
-    {ok, Req, State}.
-
- -
+
init(Req, State) ->
+    Req2 = cowboy_req:stream_reply(200, Req),
+    {cowboy_loop, Req2, State}.
+
+info(eof, Req, State) ->
+    {stop, Req, State};
+info({event, Data}, Req, State) ->
+    cowboy_req:stream_body(Data, nofin, Req),
+    {ok, Req, State};
+info(_Msg, Req, State) ->
+    {ok, Req, State}.
+

Cleaning up

-
-

It is recommended that you set the connection header to -close when replying, as this process may be reused for -a subsequent request.

-

Please refer to the Handlers chapter -for general instructions about cleaning up.

-
- -
+

It is recommended that you set the connection header to close when replying, as this process may be reused for a subsequent request.

+

Please refer to the Handlers chapter for general instructions about cleaning up.

Hibernate

-
-

To save memory, you may hibernate the process in between -messages received. This is done by returning the atom -hibernate as part of the loop tuple callbacks normally -return. Just add the atom at the end and Cowboy will hibernate -accordingly.

-
-
+

To save memory, you may hibernate the process in between messages received. This is done by returning the atom hibernate as part of the loop tuple callbacks normally return. Just add the atom at the end and Cowboy will hibernate accordingly.

+ diff --git a/docs/en/cowboy/2.3/guide/middlewares/index.html b/docs/en/cowboy/2.3/guide/middlewares/index.html index a02ce678..6dbf8869 100644 --- a/docs/en/cowboy/2.3/guide/middlewares/index.html +++ b/docs/en/cowboy/2.3/guide/middlewares/index.html @@ -62,92 +62,38 @@

Middlewares

-

Cowboy delegates the request processing to middleware components. -By default, two middlewares are defined, for the routing and handling -of the request, as is detailed in most of this guide.

-

Middlewares give you complete control over how requests are to be -processed. You can add your own middlewares to the mix or completely -change the chain of middlewares as needed.

-

Cowboy will execute all middlewares in the given order, unless one -of them decides to stop processing.

-
+

Cowboy delegates the request processing to middleware components. By default, two middlewares are defined, for the routing and handling of the request, as is detailed in most of this guide.

+

Middlewares give you complete control over how requests are to be processed. You can add your own middlewares to the mix or completely change the chain of middlewares as needed.

+

Cowboy will execute all middlewares in the given order, unless one of them decides to stop processing.

Usage

-
-

Middlewares only need to implement a single callback: execute/2. -It is defined in the cowboy_middleware behavior.

-

This callback has two arguments. The first is the Req object. -The second is the environment.

-

Middlewares can return one of three different values:

-
    -
  • -

    -{ok, Req, Env} to continue the request processing -

    +

    Middlewares only need to implement a single callback: execute/2. It is defined in the cowboy_middleware behavior.

    +

    This callback has two arguments. The first is the Req object. The second is the environment.

    +

    Middlewares can return one of three different values:

    +
    • {ok, Req, Env} to continue the request processing
      • -
    • -

      -{suspend, Module, Function, Args} to hibernate -

      +
    • {suspend, Module, Function, Args} to hibernate
      • -
    • -

      -{stop, Req} to stop processing and move on to the next request -

      +
    • {stop, Req} to stop processing and move on to the next request
      • -
-

Of note is that when hibernating, processing will resume on the given -MFA, discarding all previous stacktrace. Make sure you keep the Req -and Env in the arguments of this MFA for later use.

-

If an error happens during middleware processing, Cowboy will not try -to send an error back to the socket, the process will just crash. It -is up to the middleware to make sure that a reply is sent if something -goes wrong.

-
-
-
+ +

Of note is that when hibernating, processing will resume on the given MFA, discarding all previous stacktrace. Make sure you keep the Req and Env in the arguments of this MFA for later use.

+

If an error happens during middleware processing, Cowboy will not try to send an error back to the socket, the process will just crash. It is up to the middleware to make sure that a reply is sent if something goes wrong.

Configuration

-
-

The middleware environment is defined as the env protocol option. -In the previous chapters we saw it briefly when we needed to pass -the routing information. It is a list of tuples with the first -element being an atom and the second any Erlang term.

-

Two values in the environment are reserved:

-
    -
  • -

    -listener contains the name of the listener -

    +

    The middleware environment is defined as the env protocol option. In the previous chapters we saw it briefly when we needed to pass the routing information. It is a list of tuples with the first element being an atom and the second any Erlang term.

    +

    Two values in the environment are reserved:

    +
    • listener contains the name of the listener
      • -
    • -

      -result contains the result of the processing -

      +
    • result contains the result of the processing
      • -
-

The listener value is always defined. The result value can be -set by any middleware. If set to anything other than ok, Cowboy -will not process any subsequent requests on this connection.

-

The middlewares that come with Cowboy may define or require other -environment values to perform.

-

You can update the environment by calling the cowboy:set_env/3 -convenience function, adding or replacing a value in the environment.

-
-
-
+ +

The listener value is always defined. The result value can be set by any middleware. If set to anything other than ok, Cowboy will not process any subsequent requests on this connection.

+

The middlewares that come with Cowboy may define or require other environment values to perform.

+

You can update the environment by calling the cowboy:set_env/3 convenience function, adding or replacing a value in the environment.

Routing middleware

-
-

The routing middleware requires the dispatch value. If routing -succeeds, it will put the handler name and options in the handler -and handler_opts values of the environment, respectively.

-
-
-
+

The routing middleware requires the dispatch value. If routing succeeds, it will put the handler name and options in the handler and handler_opts values of the environment, respectively.

Handler middleware

-
-

The handler middleware requires the handler and handler_opts -values. It puts the result of the request handling into result.

-
-
+

The handler middleware requires the handler and handler_opts values. It puts the result of the request handling into result.

+ diff --git a/docs/en/cowboy/2.3/guide/migrating_from_1.0/index.html b/docs/en/cowboy/2.3/guide/migrating_from_1.0/index.html index c284d717..b8a30584 100644 --- a/docs/en/cowboy/2.3/guide/migrating_from_1.0/index.html +++ b/docs/en/cowboy/2.3/guide/migrating_from_1.0/index.html @@ -62,388 +62,120 @@

Migrating from Cowboy 1.0 to 2.0

-

A lot has changed between Cowboy 1.0 and 2.0. The cowboy_req -interface in particular has seen a massive revamp. Hooks are -gone, their functionality can now be achieved via stream -handlers.

-

The documentation has seen great work, in particular the -manual. Each module and each function now has its own dedicated -manual page with full details and examples.

-
+

A lot has changed between Cowboy 1.0 and 2.0. The cowboy_req interface in particular has seen a massive revamp. Hooks are gone, their functionality can now be achieved via stream handlers.

+

The documentation has seen great work, in particular the manual. Each module and each function now has its own dedicated manual page with full details and examples.

Compatibility

-
-

Compatibility with Erlang/OTP R16, 17 and 18 has been dropped. -Erlang/OTP 19.0 or above is required. It is non-trivial to -make Cowboy 2.0 work with older Erlang/OTP versions.

-

Cowboy 2.0 is not compatible with Cowlib versions older than -2.0. It should be compatible with Ranch 1.0 or above, however -it has not been tested with Ranch versions older than 1.4.

-

Cowboy 2.0 is tested on Arch Linux, Ubuntu, FreeBSD, Windows -and OSX. It is tested with every point release (latest patch -release) and also with HiPE on the most recent release.

-

Cowboy 2.0 now comes with Erlang.mk templates.

-
-
-
+

Compatibility with Erlang/OTP R16, 17 and 18 has been dropped. Erlang/OTP 19.0 or above is required. It is non-trivial to make Cowboy 2.0 work with older Erlang/OTP versions.

+

Cowboy 2.0 is not compatible with Cowlib versions older than 2.0. It should be compatible with Ranch 1.0 or above, however it has not been tested with Ranch versions older than 1.4.

+

Cowboy 2.0 is tested on Arch Linux, Ubuntu, FreeBSD, Windows and OSX. It is tested with every point release (latest patch release) and also with HiPE on the most recent release.

+

Cowboy 2.0 now comes with Erlang.mk templates.

Features added

-
-
    -
  • -

    -The HTTP/2 protocol is now supported. -

    -
    • -
  • -

    -Cowboy no longer uses only one process per connection. - It now uses one process per connection plus one process - per request by default. This is necessary for HTTP/2. - There might be a slight drop in performance for HTTP/1.1 - connections due to this change. -

    -
    • -
  • -

    -Cowboy internals have largely been reworked in order to - support HTTP/2. This opened the way to stream handlers, - which are a chain of modules that are called whenever - something happens relating to a request/response. -

    -
    • -
  • -

    -The cowboy_stream_h stream handler has been added. - It provides most of Cowboy’s default behavior. -

    -
    • -
  • -

    -The cowboy_compress_h stream handler has been added. - It compresses responses when possible. It’s worth noting - that it compresses in more cases than Cowboy 1.0 ever did. -

    -
    • -
  • -

    -Because of the many changes in the internals of Cowboy, - many options have been added or modified. Of note is that - the Websocket options are now given per handler rather - than for the entire listener. -

    -
    • -
  • -

    -Websocket permessage-deflate compression is now supported - via the compress option. -

    -
    • -
  • -

    -Static file handlers will now correctly find files found - in .ez archives. -

    -
    • -
  • -

    -Constraints have been generalized and are now used not only - in the router but also in some cowboy_req functions. Their - interface has also been modified to allow for reverse - operations and formatting of errors. -

    -
    • -
-
-
-
+

Features removed

-
-
    -
  • -

    -SPDY support has been removed. Use HTTP/2 instead. -

    -
    • -
  • -

    -Hooks have been removed. Use stream handlers instead. -

    -
    • -
  • -

    -The undocumented waiting_stream hack has been removed. - It allowed disabling chunked transfer-encoding for HTTP/1.1. - It has no equivalent in Cowboy 2.0. Open a ticket if necessary. -

    -
    • -
  • -

    -Sub protocols still exist, but their interface has largely changed - and they are no longer documented for the time being. -

    -
    • -
-
-
-
+

Changed behaviors

-
-
    -
  • -

    -The handler behaviors have been renamed and are now cowboy_handler, - cowboy_loop, cowboy_rest and cowboy_websocket. -

    -
    • -
  • -

    -Plain HTTP, loop, REST and Websocket handlers have had their - init and terminate callbacks unified. They now all use the - init/2 and terminate/3 callbacks. The latter is now optional. - The terminate reason has now been documented for all handlers. -

    -
    • -
  • -

    -The tuple returned to switch to a different handler type has - changed. It now takes the form {Module, Req, State} or - {Module, Req, State, Opts}, where Opts is a map of options - to configure the handler. The timeout and hibernate options - must now be specified using this map, where applicable. -

    -
    • -
  • -

    -All behaviors that used to accept halt or shutdown tuples - as a return value no longer do so. The return value is now - a stop tuple, consistent across Cowboy. -

    -
    • -
  • -

    -Middlewares can no longer return an error tuple. They have - to send the response and return a stop tuple instead. -

    -
    • -
  • -

    -The known_content_type REST handler callback has been removed - as it was found unnecessary. -

    -
    • -
  • -

    -Websocket handlers have both the normal init/2 and - an optional websocket_init/1 function. The reason for - that exception is that the websocket_* callbacks execute - in a separate process from the init/2 callback, and it - was therefore not obvious how timers or monitors should - be setup properly. They are effectively initializing the - handler before and after the HTTP/1.1 upgrade. -

    -
    • -
  • -

    -Websocket handlers can now send frames directly from - websocket_init/1. The frames will be sent immediately - after the handshake. -

    -
    • -
  • -

    -Websocket handler callbacks no longer receive the Req - argument. The init/2 callback still receives it and - can be used to extract relevant information. The terminate/3 - callback, if implemented, may still receive the Req - (see next bullet point). -

    -
    • -
  • -

    -Websocket handlers have a new req_filter option that - can be used to customize how much information should be - discarded from the Req object after the handshake. Note - that the Req object is only available in terminate/3 - past that point. -

    -
    • -
  • -

    -Websocket handlers have their timeout default changed - from infinity to 60 seconds. -

    -
    • -
-
-
-
+

New functions

-
-
    -
  • -

    -The cowboy_req:scheme/1 function has been added. -

    -
    • -
  • -

    -The cowboy_req:uri/1,2 function has been added, replacing the - less powerful functions cowboy_req:url/1 and cowboy_req:host_url/1. -

    -
    • -
  • -

    -The functions cowboy_req:match_qs/2 and cowboy_req:match_cookies/2 - allow matching query string and cookies against constraints. -

    -
    • -
  • -

    -The function cowboy_req:set_resp_cookie/3 has been added to - complement cowboy_req:set_resp_cookie/4. -

    -
    • -
  • -

    -The functions cowboy_req:resp_header/2,3 and cowboy_req:resp_headers/1 - have been added. They can be used to retrieve response headers - that were previously set. -

    -
    • -
  • -

    -The function cowboy_req:set_resp_headers/2 has been added. It - allows setting many response headers at once. -

    -
    • -
  • -

    -The functions cowboy_req:push/3,4 can be used to push resources - for protocols that support it (by default only HTTP/2). -

    -
    • -
-
-
-
+

Changed functions

-
-
    -
  • -

    -The cowboy:start_http/4 function was renamed to cowboy:start_clear/3. -

    -
    • -
  • -

    -The cowboy:start_https/4 function was renamed to cowboy:start_tls/3. -

    -
    • -
  • -

    -Most, if not all, functions in the cowboy_req module have been modified. - Please consult the changelog of each individual functions. The changes - are mainly about simplifying and clarifying the interface. The Req is no - longer returned when not necessary, maps are used wherever possible, - and some functions have been renamed. -

    -
    • -
  • -

    -The position of the Opts argument for cowboy_req:set_resp_cookie/4 - has changed to improve consistency. It is now the last argument. -

    -
    • -
-
-
-
+

Removed functions

-
-
    -
  • -

    -The functions cowboy_req:url/1 and cowboy_req:host_url/1 have been - removed in favor of the new function cowboy_req:uri/1,2. -

    -
    • -
  • -

    -The functions cowboy_req:meta/2,3 and cowboy_req:set_meta/3 have - been removed. The Req object is now a public map, therefore they became - unnecessary. -

    -
    • -
  • -

    -The functions cowboy_req:set_resp_body_fun/2,3 have been removed. - For sending files, the function cowboy_req:set_resp_body/2 can now - take a sendfile tuple. -

    -
    • -
  • -

    -Remove many undocumented functions from cowboy_req, including the - functions cowboy_req:get/2 and cowboy_req:set/3. -

    -
    • -
-
-
-
+

Other changes

-
-
    -
  • -

    -The correct percent-decoding algorithm is now used for path elements - during routing. It will no longer decode + characters. -

    -
    • -
  • -

    -The router will now properly handle path segments . and ... -

    -
    • -
  • -

    -Routing behavior has changed for URIs containing latin1 characters. - They are no longer allowed. URIs are expected to be in UTF-8 once - they are percent-decoded. -

    -
    • -
  • -

    -Clients that send multiple headers of the same name - will have the values of those headers concatenated into a - comma-separated list. This is of special importance in the - case of the content-type header, as previously only the - first value was used in the content_types_accepted/2 step - in REST handlers. -

    -
    • -
  • -

    -Etag comparison in REST handlers has been fixed. Some requests may - now fail when they succeeded in the past. -

    -
    • -
  • -

    -The If-*-Since headers are now ignored in REST handlers if - the corresponding If*-Match header exist. The former is - largely a backward compatible header and this shouldn’t create - any issue. The new behavior follows the current RFCs more closely. -

    -
    • -
  • -

    -The static file handler has been improved to handle more special - characters on systems that accept them. -

    -
    • -
-
-
+ + diff --git a/docs/en/cowboy/2.3/guide/migrating_from_2.0/index.html b/docs/en/cowboy/2.3/guide/migrating_from_2.0/index.html index d547b8c6..fa7978d1 100644 --- a/docs/en/cowboy/2.3/guide/migrating_from_2.0/index.html +++ b/docs/en/cowboy/2.3/guide/migrating_from_2.0/index.html @@ -62,188 +62,55 @@

Migrating from Cowboy 2.0 to 2.1

-

Cowboy 2.1 focused on adding features that were temporarily -removed in Cowboy 2.0. A number of bugs found in the 2.0 -release were also fixed.

-
+

Cowboy 2.1 focused on adding features that were temporarily removed in Cowboy 2.0. A number of bugs found in the 2.0 release were also fixed.

Features added

-
-
    -
  • -

    -It is now possible to obtain the client TLS certificate - and the local IP/port for the connection from the Req object. -

    +
    • It is now possible to obtain the client TLS certificate and the local IP/port for the connection from the Req object.
      • -
    • -

      -Informational responses (1XX responses) can now be sent. - They must be sent before initiating the final response. -

      +
    • Informational responses (1XX responses) can now be sent. They must be sent before initiating the final response.
      • -
    • -

      -The expect: 100-continue header is now handled - automatically. The 100 response will be sent on the - first cowboy_req:read_body/2,3,4 call. This only applies - when using the default cowboy_stream_h stream handler. -

      +
    • The expect: 100-continue header is now handled automatically. The 100 response will be sent on the first cowboy_req:read_body/2,3,4 call. This only applies when using the default cowboy_stream_h stream handler.
      • -
-
-
-
+

Experimental features added

-
-

Experimental features are previews of features that will be -added in a future release. They are not documented and their -interface may change at any time. You are welcome to try them -and provide feedback.

-
    -
  • -

    -The cowboy_metrics_h stream handler can be used to - extract metrics out of Cowboy. It must be used first in - the list of stream handlers, and will record all events - related to requests, responses and spawned processes. - When the stream terminates it will pass this information - to a user-defined callback. -

    +

    Experimental features are previews of features that will be added in a future release. They are not documented and their interface may change at any time. You are welcome to try them and provide feedback.

    +
    • The cowboy_metrics_h stream handler can be used to extract metrics out of Cowboy. It must be used first in the list of stream handlers, and will record all events related to requests, responses and spawned processes. When the stream terminates it will pass this information to a user-defined callback.
      • -
    • -

      -The cowboy_tracer_h stream handler can be used to setup - automatic tracing of specific requests. You can conditionally - enable tracing based on a function, header, path or any other - element from the request and the trace will apply to the - entire connection and any processes created by it. This is - meant to be used for debugging both in tests and production. -

      +
    • The cowboy_tracer_h stream handler can be used to setup automatic tracing of specific requests. You can conditionally enable tracing based on a function, header, path or any other element from the request and the trace will apply to the entire connection and any processes created by it. This is meant to be used for debugging both in tests and production.
      • -
-
-
-
+

Changed behaviors

-
-
    -
  • -

    -The cowboy_rest handler now implements a mechanism for - switching to a different type of handler from any callback - where stop is also allowed. Switch by returning - {switch_handler, Module} or {switch_handler, Module, Opts}. - This is especially useful for switching to cowboy_loop - for streaming the request or response body. -

    +
    • The cowboy_rest handler now implements a mechanism for switching to a different type of handler from any callback where stop is also allowed. Switch by returning {switch_handler, Module} or {switch_handler, Module, Opts}. This is especially useful for switching to cowboy_loop for streaming the request or response body.
      • -
    • -

      -REST callbacks that do not allow stop as a return value - are now explicitly listed in the documentation. -

      +
    • REST callbacks that do not allow stop as a return value are now explicitly listed in the documentation.
      • -
-
-
-
+

New functions

-
-
    -
  • -

    -The function cowboy_req:sock/1 returns the IP/port - of the local socket. -

    +
    • The function cowboy_req:sock/1 returns the IP/port of the local socket.
      • -
    • -

      -The function cowboy_req:cert/1 returns the client - TLS certificate or undefined if it isn’t available. -

      +
    • The function cowboy_req:cert/1 returns the client TLS certificate or undefined if it isn't available.
      • -
    • -

      -The function cowboy_req:inform/2,3 sends an - informational response. -

      +
    • The function cowboy_req:inform/2,3 sends an informational response.
      • -
-
-
-
+

Bugs fixed

-
-
    -
  • -

    -Ensure HTTP/2 connections are not closed prematurely - when the user code does not read the request body. -

    +
    • Ensure HTTP/2 connections are not closed prematurely when the user code does not read the request body.
      • -
    • -

      -Ensure HTTP/1.1 streams are not terminated too early. - Their behavior is now consistent with the HTTP/2 code - where the stream handler is only terminated when the - stop command is returned. -

      +
    • Ensure HTTP/1.1 streams are not terminated too early. Their behavior is now consistent with the HTTP/2 code where the stream handler is only terminated when the stop command is returned.
      • -
    • -

      -Sending zero-sized data from stream handlers or from - cowboy_req:stream_body/3 could lead to issues with - HTTP/1.1. This has been fixed. -

      +
    • Sending zero-sized data from stream handlers or from cowboy_req:stream_body/3 could lead to issues with HTTP/1.1. This has been fixed.
      • -
    • -

      -The final chunk sent by Cowboy when it terminates a - chunked body after the handler process exits was not - passed through stream handlers, which could lead to - issues when cowboy_compress_h was being used. This - is now corrected. -

      +
    • The final chunk sent by Cowboy when it terminates a chunked body after the handler process exits was not passed through stream handlers, which could lead to issues when cowboy_compress_h was being used. This is now corrected.
      • -
    • -

      -The stream handler state was discarded in some cases - where Cowboy had to send a response or response data - automatically when ending a stream. This has now - been corrected. -

      +
    • The stream handler state was discarded in some cases where Cowboy had to send a response or response data automatically when ending a stream. This has now been corrected.
      • -
    • -

      -The stream handler callback terminate/3 will now be - called when switching to another protocol using the - command switch_protocol. This doesn’t apply when - doing upgrades to HTTP/2 as those occur before the - stream is initialized. -

      +
    • The stream handler callback terminate/3 will now be called when switching to another protocol using the command switch_protocol. This doesn't apply when doing upgrades to HTTP/2 as those occur before the stream is initialized.
      • -
    • -

      -Cowlib has been updated to 2.0.1 to fix an issue with - Websocket compression when using Erlang/OTP 20.1. Note - that at the time of writing all 20.1 versions (from - 20.1 to 20.1.4) have issues when compression is enabled. - It is expected to work properly from 20.1.5 onward. In - the meantime it is recommended to run the plain 20.1 - release and disable Websocket compression, or use a - release before 20.1. -

      +
    • Cowlib has been updated to 2.0.1 to fix an issue with Websocket compression when using Erlang/OTP 20.1. Note that at the time of writing all 20.1 versions (from 20.1 to 20.1.4) have issues when compression is enabled. It is expected to work properly from 20.1.5 onward. In the meantime it is recommended to run the plain 20.1 release and disable Websocket compression, or use a release before 20.1.
      • -
    • -

      -Cowboy will no longer crash when the cowboy_clock - process is not running. This can happen when Cowboy - is being restarted during upgrades, for example. -

      +
    • Cowboy will no longer crash when the cowboy_clock process is not running. This can happen when Cowboy is being restarted during upgrades, for example.
      • -
-
-
+ + diff --git a/docs/en/cowboy/2.3/guide/migrating_from_2.1/index.html b/docs/en/cowboy/2.3/guide/migrating_from_2.1/index.html index 6d6fed21..364c295f 100644 --- a/docs/en/cowboy/2.3/guide/migrating_from_2.1/index.html +++ b/docs/en/cowboy/2.3/guide/migrating_from_2.1/index.html @@ -62,203 +62,66 @@

Migrating from Cowboy 2.1 to 2.2

-

Cowboy 2.2 focused on adding features required for writing -gRPC servers and on completing test suites for the core -HTTP RFCs, fixing many bugs along the way.

-
+

Cowboy 2.2 focused on adding features required for writing gRPC servers and on completing test suites for the core HTTP RFCs, fixing many bugs along the way.

Features added

-
-
    -
  • -

    -Add support for sending trailers at the end of response bodies. - Trailers are additional header fields that may be sent after the - body to add more information to the response. Their usage is - required in gRPC servers. They are optional and may be discarded - in other scenarios (for example if the request goes through an - HTTP/1.0 proxy, as HTTP/1.0 does not support trailers). -

    +
    • Add support for sending trailers at the end of response bodies. Trailers are additional header fields that may be sent after the body to add more information to the response. Their usage is required in gRPC servers. They are optional and may be discarded in other scenarios (for example if the request goes through an HTTP/1.0 proxy, as HTTP/1.0 does not support trailers).
      • -
    • -

      -The max_skip_body_length option was added to cowboy_http. - It controls how much of a request body Cowboy is willing to skip - when the handler did not touch it. If the remaining body size is - too large Cowboy instead closes the connection. It defaults to 1MB. -

      +
    • The max_skip_body_length option was added to cowboy_http. It controls how much of a request body Cowboy is willing to skip when the handler did not touch it. If the remaining body size is too large Cowboy instead closes the connection. It defaults to 1MB.
      • -
    • -

      -The CONNECT and TRACE methods are now rejected as they are - currently not implemented and must be handled differently than - other methods. They will be implemented in a future release. -

      +
    • The CONNECT and TRACE methods are now rejected as they are currently not implemented and must be handled differently than other methods. They will be implemented in a future release.
      • -
-
-
-
+

New functions

-
-
    -
  • -

    -The function stream_trailers/2 has been added. It terminates - a stream and adds trailer fields at the end of the response. A - corresponding stream handler command {trailers, Trailers} - has also been added. -

    +
    • The function stream_trailers/2 has been added. It terminates a stream and adds trailer fields at the end of the response. A corresponding stream handler command {trailers, Trailers} has also been added.
      • -
-
-
-
+

Bugs fixed

-
-
    -
  • -

    -Test suites for the core HTTP RFCs RFC7230, RFC7231 and RFC7540 - have been completed. Many of the bugs listed here were fixed as - a result of this work. -

    +
    • Test suites for the core HTTP RFCs RFC7230, RFC7231 and RFC7540 have been completed. Many of the bugs listed here were fixed as a result of this work.
      • -
    • -

      -Many HTTP/2 edge cases when clients are misbehaving have been - corrected. This includes many cases where the request is malformed - (for example when a pseudo-header is present twice). -

      +
    • Many HTTP/2 edge cases when clients are misbehaving have been corrected. This includes many cases where the request is malformed (for example when a pseudo-header is present twice).
      • -
    • -

      -When the HTTP/2 SETTINGS_INITIAL_WINDOW_SIZE value changes, - Cowboy now properly updates the flow control windows. -

      +
    • When the HTTP/2 SETTINGS_INITIAL_WINDOW_SIZE value changes, Cowboy now properly updates the flow control windows.
      • -
    • -

      -HTTP/2 could mistakenly log stray messages that actually were - expected. This is no longer the case. -

      +
    • HTTP/2 could mistakenly log stray messages that actually were expected. This is no longer the case.
      • -
    • -

      -We no longer send a GOAWAY frame when the HTTP/2 preface is invalid. -

      +
    • We no longer send a GOAWAY frame when the HTTP/2 preface is invalid.
      • -
    • -

      -Some values in the Req object of pushed requests were in the - wrong type. They are now the expected binary instead of iolist. -

      +
    • Some values in the Req object of pushed requests were in the wrong type. They are now the expected binary instead of iolist.
      • -
    • -

      -A response body was sometimes sent in response to HEAD requests - when using HTTP/2. The body is now ignored. -

      +
    • A response body was sometimes sent in response to HEAD requests when using HTTP/2. The body is now ignored.
      • -
    • -

      -The max_headers option for cowboy_http was not always respected - depending on the contents of the buffer. The limit is now strict. -

      +
    • The max_headers option for cowboy_http was not always respected depending on the contents of the buffer. The limit is now strict.
      • -
    • -

      -When an early error occurred on the HTTP/1.1 request line, the - partial Req given to stream handlers was missing the ref and - peer information. This has been corrected. -

      +
    • When an early error occurred on the HTTP/1.1 request line, the partial Req given to stream handlers was missing the ref and peer information. This has been corrected.
      • -
    • -

      -Absolute URIs with a userinfo component, or without an authority - component, are now properly rejected for HTTP/1.0 and HTTP/1.1. -

      +
    • Absolute URIs with a userinfo component, or without an authority component, are now properly rejected for HTTP/1.0 and HTTP/1.1.
      • -
    • -

      -Whitespace is no longer allowed in header lines before the colon. -

      +
    • Whitespace is no longer allowed in header lines before the colon.
      • -
    • -

      -408 responses to HTTP/1.1 requests now properly include a - connection: close header indicating that we are going to - close the connection. This header will also be sent for - other early errors resulting in the closing of the connection. -

      +
    • 408 responses to HTTP/1.1 requests now properly include a connection: close header indicating that we are going to close the connection. This header will also be sent for other early errors resulting in the closing of the connection.
      • -
    • -

      -When both the transfer-encoding and content-length headers are - sent in an HTTP/1.1 request, the transfer-encoding now takes - precedence over the content-length header and the latter is - removed from the Req object. -

      +
    • When both the transfer-encoding and content-length headers are sent in an HTTP/1.1 request, the transfer-encoding now takes precedence over the content-length header and the latter is removed from the Req object.
      • -
    • -

      -A 400 response is now returned when the transfer-encoding - header is invalid or contains any transfer-coding other - than chunked. -

      +
    • A 400 response is now returned when the transfer-encoding header is invalid or contains any transfer-coding other than chunked.
      • -
    • -

      -Invalid chunk sizes are now rejected immediately. -

      +
    • Invalid chunk sizes are now rejected immediately.
      • -
    • -

      -Chunk extensions are now limited to 129 characters. They are - not used in practice and are still ignored by Cowboy. The limit - is not configurable. -

      +
    • Chunk extensions are now limited to 129 characters. They are not used in practice and are still ignored by Cowboy. The limit is not configurable.
      • -
    • -

      -The final chunk was mistakenly sent in responses to HEAD - requests. This is now corrected. -

      +
    • The final chunk was mistakenly sent in responses to HEAD requests. This is now corrected.
      • -
    • -

      -OPTIONS * requests were broken in Cowboy 2.0. They are now - working again. Both the routing and cowboy_req:uri/1,2 have - been corrected. -

      +
    • OPTIONS * requests were broken in Cowboy 2.0. They are now working again. Both the routing and cowboy_req:uri/1,2 have been corrected.
      • -
    • -

      -204 responses no longer include a content-length header. -

      +
    • 204 responses no longer include a content-length header.
      • -
    • -

      -A packet could be lost when switching to Websocket or any - other protocol via the switch_protocol command. This is - now fixed. -

      +
    • A packet could be lost when switching to Websocket or any other protocol via the switch_protocol command. This is now fixed.
      • -
    • -

      -A 426 response will now be sent when a handler requires - the client to upgrade to Websocket and the request did not - include the required headers. -

      +
    • A 426 response will now be sent when a handler requires the client to upgrade to Websocket and the request did not include the required headers.
      • -
    • -

      -Both experimental stream handlers cowboy_metrics_h and - cowboy_tracer_h received a number of fixes and improvements. -

      +
    • Both experimental stream handlers cowboy_metrics_h and cowboy_tracer_h received a number of fixes and improvements.
      • -
-
-
+ + diff --git a/docs/en/cowboy/2.3/guide/migrating_from_2.2/index.html b/docs/en/cowboy/2.3/guide/migrating_from_2.2/index.html index ced40d21..95aea629 100644 --- a/docs/en/cowboy/2.3/guide/migrating_from_2.2/index.html +++ b/docs/en/cowboy/2.3/guide/migrating_from_2.2/index.html @@ -62,108 +62,38 @@

Migrating from Cowboy 2.2 to 2.3

-

Cowboy 2.3 focused on making the Cowboy processes behave -properly according to OTP principles. This version is a -very good milestone toward that goal and most of everything -should now work. Release upgrades and a few details will -be improved in future versions.

-
+

Cowboy 2.3 focused on making the Cowboy processes behave properly according to OTP principles. This version is a very good milestone toward that goal and most of everything should now work. Release upgrades and a few details will be improved in future versions.

Features added

-
-
    -
  • -

    -Add support for all functions from the module sys. Note - that Cowboy currently does not implement the sys debugging - mechanisms as tracing is recommended instead. -

    +
    • Add support for all functions from the module sys. Note that Cowboy currently does not implement the sys debugging mechanisms as tracing is recommended instead.
      • -
    • -

      -Add a max_frame_size option for Websocket handlers - to close the connection when the client attempts to - send a frame that’s too large. It currently defaults - to infinity to avoid breaking existing code but will - be changed in a future version. -

      +
    • Add a max_frame_size option for Websocket handlers to close the connection when the client attempts to send a frame that's too large. It currently defaults to infinity to avoid breaking existing code but will be changed in a future version.
      • -
    • -

      -Update Cowlib to 2.2.1. -

      +
    • Update Cowlib to 2.2.1.
      • -
    • -

      -Add support for the 308 status code and a test suite - for RFC7538 where it is defined. -

      +
    • Add support for the 308 status code and a test suite for RFC7538 where it is defined.
      • -
-
-
-
+

Bugs fixed

-
-
    -
  • -

    -Ensure timeout options accept the value infinity as - documented. -

    +
    • Ensure timeout options accept the value infinity as documented.
      • -
    • -

      -Properly reject HTTP/2 requests with an invalid content-length - header instead of simply crashing. -

      +
    • Properly reject HTTP/2 requests with an invalid content-length header instead of simply crashing.
      • -
    • -

      -When switching from HTTP/1.1 to Websocket or user protocols - all the messages in the mailbox were flushed. Only messages - specific to cowboy_http should now be flushed. -

      +
    • When switching from HTTP/1.1 to Websocket or user protocols all the messages in the mailbox were flushed. Only messages specific to cowboy_http should now be flushed.
      • -
    • -

      -Parsing of the x-forwarded-for header has been corrected. - It now supports IPv6 addresses both with and without port. -

      +
    • Parsing of the x-forwarded-for header has been corrected. It now supports IPv6 addresses both with and without port.
      • -
    • -

      -Websocket subprotocol tokens are now parsed in a case - insensitive manner, according to the spec. -

      +
    • Websocket subprotocol tokens are now parsed in a case insensitive manner, according to the spec.
      • -
    • -

      -Cookies without values are now allowed. For example Cookie: foo. -

      +
    • Cookies without values are now allowed. For example Cookie: foo.
      • -
    • -

      -Colons are now allowed within path segments in routes provided - to cowboy_router:compile/1 as long as they are not the first - character of the path segment. -

      +
    • Colons are now allowed within path segments in routes provided to cowboy_router:compile/1 as long as they are not the first character of the path segment.
      • -
    • -

      -The cowboy_req:delete_resp_header/2 function will no longer - crash when no response header was set before calling it. -

      +
    • The cowboy_req:delete_resp_header/2 function will no longer crash when no response header was set before calling it.
      • -
    • -

      -A miscount of the output HTTP/2 flow control window has been - fixed. It prevented sending the response body fully to some - clients. The issue only affected response bodies sent as iolists. -

      +
    • A miscount of the output HTTP/2 flow control window has been fixed. It prevented sending the response body fully to some clients. The issue only affected response bodies sent as iolists.
      • -
-
-
+ + diff --git a/docs/en/cowboy/2.3/guide/modern_web/index.html b/docs/en/cowboy/2.3/guide/modern_web/index.html index 4b1a8406..2f9cc837 100644 --- a/docs/en/cowboy/2.3/guide/modern_web/index.html +++ b/docs/en/cowboy/2.3/guide/modern_web/index.html @@ -62,115 +62,38 @@

The modern Web

-

Cowboy is a server for the modern Web. This chapter explains -what it means and details all the standards involved.

-

Cowboy supports all the standards listed in this document.

-
+

Cowboy is a server for the modern Web. This chapter explains what it means and details all the standards involved.

+

Cowboy supports all the standards listed in this document.

HTTP/2

-
-

HTTP/2 is the most efficient protocol for consuming Web -services. It enables clients to keep a connection open -for long periods of time; to send requests concurrently; -to reduce the size of requests through HTTP headers -compression; and more. The protocol is binary, greatly -reducing the resources needed to parse it.

-

HTTP/2 also enables the server to push messages to the -client. This can be used for various purposes, including -the sending of related resources before the client requests -them, in an effort to reduce latency. This can also be used -to enable bidirectional communication.

-

Cowboy provides transparent support for HTTP/2. Clients -that know it can use it; others fall back to HTTP/1.1 -automatically.

-

HTTP/2 is compatible with the HTTP/1.1 semantics.

-

HTTP/2 is defined by RFC 7540 and RFC 7541.

-
-
-
+

HTTP/2 is the most efficient protocol for consuming Web services. It enables clients to keep a connection open for long periods of time; to send requests concurrently; to reduce the size of requests through HTTP headers compression; and more. The protocol is binary, greatly reducing the resources needed to parse it.

+

HTTP/2 also enables the server to push messages to the client. This can be used for various purposes, including the sending of related resources before the client requests them, in an effort to reduce latency. This can also be used to enable bidirectional communication.

+

Cowboy provides transparent support for HTTP/2. Clients that know it can use it; others fall back to HTTP/1.1 automatically.

+

HTTP/2 is compatible with the HTTP/1.1 semantics.

+

HTTP/2 is defined by RFC 7540 and RFC 7541.

HTTP/1.1

-
-

HTTP/1.1 is the previous version of the HTTP protocol. -The protocol itself is text-based and suffers from numerous -issues and limitations. In particular it is not possible -to execute requests concurrently (though pipelining is -sometimes possible), and it’s also sometimes difficult -to detect that a client disconnected.

-

HTTP/1.1 does provide very good semantics for interacting -with Web services. It defines the standard methods, headers -and status codes used by HTTP/1.1 and HTTP/2 clients and -servers.

-

HTTP/1.1 also defines compatibility with an older version -of the protocol, HTTP/1.0, which was never really standardized -across implementations.

-

The core of HTTP/1.1 is defined by RFC 7230, RFC 7231, -RFC 7232, RFC 7233, RFC 7234 and RFC 7235. Numerous RFCs -and other specifications exist defining additional HTTP -methods, status codes, headers or semantics.

-
-
-
+

HTTP/1.1 is the previous version of the HTTP protocol. The protocol itself is text-based and suffers from numerous issues and limitations. In particular it is not possible to execute requests concurrently (though pipelining is sometimes possible), and it's also sometimes difficult to detect that a client disconnected.

+

HTTP/1.1 does provide very good semantics for interacting with Web services. It defines the standard methods, headers and status codes used by HTTP/1.1 and HTTP/2 clients and servers.

+

HTTP/1.1 also defines compatibility with an older version of the protocol, HTTP/1.0, which was never really standardized across implementations.

+

The core of HTTP/1.1 is defined by RFC 7230, RFC 7231, RFC 7232, RFC 7233, RFC 7234 and RFC 7235. Numerous RFCs and other specifications exist defining additional HTTP methods, status codes, headers or semantics.

Websocket

-
-

Websocket is a protocol built on top of HTTP/1.1 -that provides a two-ways communication channel between the client and -the server. Communication is asynchronous and can occur concurrently.

-

It consists of a Javascript object allowing setting up a -Websocket connection to the server, and a binary based -protocol for sending data to the server or the client.

-

Websocket connections can transfer either UTF-8 encoded text -data or binary data. The protocol also includes support for -implementing a ping/pong mechanism, allowing the server and -the client to have more confidence that the connection is still -alive.

-

A Websocket connection can be used to transfer any kind of data, -small or big, text or binary. Because of this Websocket is -sometimes used for communication between systems.

-

Websocket messages have no semantics on their own. Websocket -is closer to TCP in that aspect, and requires you to design -and implement your own protocol on top of it; or adapt an -existing protocol to Websocket.

-

Cowboy provides an interface known as Websocket handlers -that gives complete control over a Websocket connection.

-

The Websocket protocol is defined by RFC 6455.

-
-
-
+

Websocket is a protocol built on top of HTTP/1.1 that provides a two-ways communication channel between the client and the server. Communication is asynchronous and can occur concurrently.

+

It consists of a Javascript object allowing setting up a Websocket connection to the server, and a binary based protocol for sending data to the server or the client.

+

Websocket connections can transfer either UTF-8 encoded text data or binary data. The protocol also includes support for implementing a ping/pong mechanism, allowing the server and the client to have more confidence that the connection is still alive.

+

A Websocket connection can be used to transfer any kind of data, small or big, text or binary. Because of this Websocket is sometimes used for communication between systems.

+

Websocket messages have no semantics on their own. Websocket is closer to TCP in that aspect, and requires you to design and implement your own protocol on top of it; or adapt an existing protocol to Websocket.

+

Cowboy provides an interface known as Websocket handlers that gives complete control over a Websocket connection.

+

The Websocket protocol is defined by RFC 6455.

Long-lived requests

-
-

Cowboy provides an interface that can be used to support -long-polling or to stream large amounts of data reliably, -including using Server-Sent Events.

-

Long-polling is a mechanism in which the client performs -a request which may not be immediately answered by the -server. It allows clients to request resources that may -not currently exist, but are expected to be created soon, -and which will be returned as soon as they are.

-

Long-polling is essentially a hack, but it is widely used -to overcome limitations on older clients and servers.

-

Server-Sent Events is a small protocol defined as a media -type, text/event-stream, along with a new HTTP header, -Last-Event-ID. It is defined in the EventSource W3C -specification.

-

Cowboy provides an interface known as loop handlers -that facilitates the implementation of long-polling or stream -mechanisms. It works regardless of the underlying protocol.

-
-
-
+

Cowboy provides an interface that can be used to support long-polling or to stream large amounts of data reliably, including using Server-Sent Events.

+

Long-polling is a mechanism in which the client performs a request which may not be immediately answered by the server. It allows clients to request resources that may not currently exist, but are expected to be created soon, and which will be returned as soon as they are.

+

Long-polling is essentially a hack, but it is widely used to overcome limitations on older clients and servers.

+

Server-Sent Events is a small protocol defined as a media type, text/event-stream, along with a new HTTP header, Last-Event-ID. It is defined in the EventSource W3C specification.

+

Cowboy provides an interface known as loop handlers that facilitates the implementation of long-polling or stream mechanisms. It works regardless of the underlying protocol.

REST

-
-

REST, or REpresentational State Transfer, -is a style of architecture for loosely connected distributed -systems. It can easily be implemented on top of HTTP.

-

REST is essentially a set of constraints to be followed. -Many of these constraints are purely architectural and -solved by simply using HTTP. Some constraints must be -explicitly followed by the developer.

-

Cowboy provides an interface known as REST handlers -that simplifies the implementation of a REST API on top of -the HTTP protocol.

-
-
+

REST, or REpresentational State Transfer, is a style of architecture for loosely connected distributed systems. It can easily be implemented on top of HTTP.

+

REST is essentially a set of constraints to be followed. Many of these constraints are purely architectural and solved by simply using HTTP. Some constraints must be explicitly followed by the developer.

+

Cowboy provides an interface known as REST handlers that simplifies the implementation of a REST API on top of the HTTP protocol.

+ diff --git a/docs/en/cowboy/2.3/guide/multipart/index.html b/docs/en/cowboy/2.3/guide/multipart/index.html index 17224160..2f5559f5 100644 --- a/docs/en/cowboy/2.3/guide/multipart/index.html +++ b/docs/en/cowboy/2.3/guide/multipart/index.html @@ -62,169 +62,107 @@

Multipart requests

-

Multipart originates from MIME, an Internet standard that -extends the format of emails.

-

A multipart message is a list of parts. A part contains -headers and a body. The body of the parts may be -of any media type, and contain text or binary data. -It is possible for parts to contain a multipart media -type.

-

In the context of HTTP, multipart is most often used -with the multipart/form-data media type. It is what -browsers use to upload files through HTML forms.

-

The multipart/byteranges is also common. It is the -media type used to send arbitrary bytes from a resource, -enabling clients to resume downloads.

-
+

Multipart originates from MIME, an Internet standard that extends the format of emails.

+

A multipart message is a list of parts. A part contains headers and a body. The body of the parts may be of any media type, and contain text or binary data. It is possible for parts to contain a multipart media type.

+

In the context of HTTP, multipart is most often used with the multipart/form-data media type. It is what browsers use to upload files through HTML forms.

+

The multipart/byteranges is also common. It is the media type used to send arbitrary bytes from a resource, enabling clients to resume downloads.

Form-data

-
-

In the normal case, when a form is submitted, the -browser will use the application/x-www-form-urlencoded -content-type. This type is just a list of keys and -values and is therefore not fit for uploading files.

-

That’s where the multipart/form-data content-type -comes in. When the form is configured to use this -content-type, the browser will create a multipart -message where each part corresponds to a field on -the form. For files, it also adds some metadata in -the part headers, like the file name.

-

A form with a text input, a file input and a select -choice box will result in a multipart message with -three parts, one for each field.

-

The browser does its best to determine the media type -of the files it sends this way, but you should not -rely on it for determining the contents of the file. -Proper investigation of the contents is recommended.

-
-
-
+

In the normal case, when a form is submitted, the browser will use the application/x-www-form-urlencoded content-type. This type is just a list of keys and values and is therefore not fit for uploading files.

+

That's where the multipart/form-data content-type comes in. When the form is configured to use this content-type, the browser will create a multipart message where each part corresponds to a field on the form. For files, it also adds some metadata in the part headers, like the file name.

+

A form with a text input, a file input and a select choice box will result in a multipart message with three parts, one for each field.

+

The browser does its best to determine the media type of the files it sends this way, but you should not rely on it for determining the contents of the file. Proper investigation of the contents is recommended.

Checking for multipart messages

-
-

The content-type header indicates the presence of -a multipart message:

-
-
-
{<<"multipart">>, <<"form-data">>, _}
-    = cowboy_req:parse_header(<<"content-type">>, Req).
-
-
-
+
{<<"multipart">>, <<"form-data">>, _}
+    = cowboy_req:parse_header(<<"content-type">>, Req).
+

Reading a multipart message

-
-

Cowboy provides two sets of functions for reading -request bodies as multipart messages.

-

The cowboy_req:read_part/1,2 functions return the -next part’s headers, if any.

-

The cowboy_req:read_part_body/1,2 functions return -the current part’s body. For large bodies you may -need to call the function multiple times.

-

To read a multipart message you need to iterate over -all its parts:

-
-
-
multipart(Req0) ->
-    case cowboy_req:read_part(Req0) of
-        {ok, _Headers, Req1} ->
-            {ok, _Body, Req} = cowboy_req:read_part_body(Req1),
-            multipart(Req);
-        {done, Req} ->
-            Req
-    end.
-

When part bodies are too large, Cowboy will return -a more tuple, and allow you to loop until the part -body has been fully read.

-

The function cow_multipart:form_data/1 can be used -to quickly obtain information about a part from a -multipart/form-data message. The function returns -a data or a file tuple depending on whether this -is a normal field or a file being uploaded.

-

The following snippet will use this function and -use different strategies depending on whether the -part is a file:

-
-
-
multipart(Req0) ->
-    case cowboy_req:read_part(Req0) of
-        {ok, Headers, Req1} ->
-            Req = case cow_multipart:form_data(Headers) of
-                {data, _FieldName} ->
-                    {ok, _Body, Req2} = cowboy_req:read_part_body(Req1),
-                    Req2;
-                {file, _FieldName, _Filename, _CType} ->
-                    stream_file(Req1)
-            end,
-            multipart(Req);
-        {done, Req} ->
-            Req
-    end.
-
-stream_file(Req0) ->
-    case cowboy_req:read_part_body(Req0) of
-        {ok, _LastBodyChunk, Req} ->
-            Req;
-        {more, _BodyChunk, Req} ->
-            stream_file(Req)
-    end.
-

Both the part header and body reading functions can take -options that will be given to the request body reading -functions. By default, cowboy_req:read_part/1 reads -up to 64KB for up to 5 seconds. cowboy_req:read_part_body/1 -has the same defaults as cowboy_req:read_body/1.

-

To change the defaults for part headers:

-
-
-
cowboy_req:read_part(Req, #{length => 128000}).
-

And for part bodies:

-
-
-
cowboy_req:read_part_body(Req, #{length => 1000000, period => 7000}).
-
- -
+
cowboy_req:read_part_body(Req, #{length => 1000000, period => 7000}).
+

Skipping unwanted parts

-
-

Part bodies do not have to be read. Cowboy will automatically -skip it when you request the next part’s body.

-

The following snippet reads all part headers and skips -all bodies:

-
-
-
multipart(Req0) ->
-    case cowboy_req:read_part(Req0) of
-        {ok, _Headers, Req} ->
-            multipart(Req);
-        {done, Req} ->
-            Req
-    end.
-

Similarly, if you start reading the body and it ends up -being too big, you can simply continue with the next part. -Cowboy will automatically skip what remains.

-

While Cowboy can skip part bodies automatically, the read -rate is not configurable. Depending on your application -you may want to skip manually, in particular if you observe -poor performance while skipping.

-

You do not have to read all parts either. You can stop -reading as soon as you find the data you need.

-
- +
multipart(Req0) ->
+    case cowboy_req:read_part(Req0) of
+        {ok, _Headers, Req} ->
+            multipart(Req);
+        {done, Req} ->
+            Req
+    end.
+ +

Similarly, if you start reading the body and it ends up being too big, you can simply continue with the next part. Cowboy will automatically skip what remains.

+

While Cowboy can skip part bodies automatically, the read rate is not configurable. Depending on your application you may want to skip manually, in particular if you observe poor performance while skipping.

+

You do not have to read all parts either. You can stop reading as soon as you find the data you need.

+ + diff --git a/docs/en/cowboy/2.3/guide/req/index.html b/docs/en/cowboy/2.3/guide/req/index.html index 9d44a310..b709f063 100644 --- a/docs/en/cowboy/2.3/guide/req/index.html +++ b/docs/en/cowboy/2.3/guide/req/index.html @@ -62,407 +62,283 @@

The Req object

-

The Req object is a variable used for obtaining information -about a request, read its body or send a response.

-

It is not really an object in the object-oriented sense. -It is a simple map that can be directly accessed or -used when calling functions from the cowboy_req module.

-

The Req object is the subject of a few different chapters. -In this chapter we will learn about the Req object and -look at how to retrieve information about the request.

-
+

The Req object is a variable used for obtaining information about a request, read its body or send a response.

+

It is not really an object in the object-oriented sense. It is a simple map that can be directly accessed or used when calling functions from the cowboy_req module.

+

The Req object is the subject of a few different chapters. In this chapter we will learn about the Req object and look at how to retrieve information about the request.

Direct access

-
-

The Req map contains a number of fields which are documented -and can be accessed directly. They are the fields that have -a direct mapping to HTTP: the request method; the HTTP -version used; the effective URI components scheme, -host, port, path and qs; the request headers; -and the connection peer address and port.

-

Note that the version field can be used to determine -whether a connection is using HTTP/2.

-

To access a field, you can simply match in the function -head. The following example sends a simple "Hello world!" -response when the method is GET, and a 405 error -otherwise.

-
-
-
init(Req0=#{method := <<"GET">>}, State) ->
-    Req = cowboy_req:reply(200, #{
-        <<"content-type">> => <<"text/plain">>
-    }, <<"Hello world!">>, Req0),
-    {ok, Req, State};
-init(Req0, State) ->
-    Req = cowboy_req:reply(405, #{
-        <<"allow">> => <<"GET">>
-    }, Req0),
-    {ok, Req, State}.
-

Any other field is internal and should not be accessed. -They may change in future releases, including maintenance -releases, without notice.

-

Modifying the Req object, while allowed, is not recommended -unless strictly necessary. If adding new fields, make sure -to namespace the field names so that no conflict can occur -with future Cowboy updates or third party projects.

-
-
-
+
init(Req0=#{method := <<"GET">>}, State) ->
+    Req = cowboy_req:reply(200, #{
+        <<"content-type">> => <<"text/plain">>
+    }, <<"Hello world!">>, Req0),
+    {ok, Req, State};
+init(Req0, State) ->
+    Req = cowboy_req:reply(405, #{
+        <<"allow">> => <<"GET">>
+    }, Req0),
+    {ok, Req, State}.
+
+

Any other field is internal and should not be accessed. They may change in future releases, including maintenance releases, without notice.

+

Modifying the Req object, while allowed, is not recommended unless strictly necessary. If adding new fields, make sure to namespace the field names so that no conflict can occur with future Cowboy updates or third party projects.

+

Introduction to the cowboy_req interface

-
-

Functions in the cowboy_req module provide access to -the request information but also various operations that -are common when dealing with HTTP requests.

-

All the functions that begin with a verb indicate an action. -Other functions simply return the corresponding value -(sometimes that value does need to be built, but the -cost of the operation is equivalent to retrieving a value).

-

Some of the cowboy_req functions return an updated Req -object. They are the read, reply, set and delete functions. -While ignoring the returned Req will not cause incorrect -behavior for some of them, it is highly recommended to -always keep and use the last returned Req object. The -manual for cowboy_req details these functions and what -modifications are done to the Req object.

-

Some of the calls to cowboy_req have side effects. This -is the case of the read and reply functions. Cowboy reads -the request body or replies immediately when the function -is called.

-

All functions will crash if something goes wrong. There -is usually no need to catch these errors, Cowboy will -send the appropriate 4xx or 5xx response depending on -where the crash occurred.

-
- -
+ +

Functions in the cowboy_req module provide access to the request information but also various operations that are common when dealing with HTTP requests.

+

All the functions that begin with a verb indicate an action. Other functions simply return the corresponding value (sometimes that value does need to be built, but the cost of the operation is equivalent to retrieving a value).

+

Some of the cowboy_req functions return an updated Req object. They are the read, reply, set and delete functions. While ignoring the returned Req will not cause incorrect behavior for some of them, it is highly recommended to always keep and use the last returned Req object. The manual for cowboy_req details these functions and what modifications are done to the Req object.

+

Some of the calls to cowboy_req have side effects. This is the case of the read and reply functions. Cowboy reads the request body or replies immediately when the function is called.

+

All functions will crash if something goes wrong. There is usually no need to catch these errors, Cowboy will send the appropriate 4xx or 5xx response depending on where the crash occurred.

Request method

-
-

The request method can be retrieved directly:

-
-
-
#{method := Method} = Req.
-

Or using a function:

-
-
-
Method = cowboy_req:method(Req).
-

The method is a case sensitive binary string. Standard -methods include GET, HEAD, OPTIONS, PATCH, POST, PUT -or DELETE.

-
-
-
+
Method = cowboy_req:method(Req).
+
+

The method is a case sensitive binary string. Standard methods include GET, HEAD, OPTIONS, PATCH, POST, PUT or DELETE.

HTTP version

-
-

The HTTP version is informational. It does not indicate that -the client implements the protocol well or fully.

-

There is typically no need to change behavior based on the -HTTP version: Cowboy already does it for you.

-

It can be useful in some cases, though. For example, one may -want to redirect HTTP/1.1 clients to use Websocket, while HTTP/2 -clients keep using HTTP/2.

-

The HTTP version can be retrieved directly:

-
-
-
#{version := Version} = Req.
-

Or using a function:

-
-
-
Version = cowboy_req:version(Req).
-

Cowboy defines the 'HTTP/1.0', 'HTTP/1.1' and 'HTTP/2' -versions. Custom protocols can define their own values as -atoms.

-
- -
+
Version = cowboy_req:version(Req).
+
+

Cowboy defines the 'HTTP/1.0', 'HTTP/1.1' and 'HTTP/2' versions. Custom protocols can define their own values as atoms.

Effective request URI

-
-

The scheme, host, port, path and query string components -of the effective request URI can all be retrieved directly:

-
-
#{
-    scheme := Scheme,
-    host := Host,
-    port := Port,
-    path := Path,
-    qs := Qs
-} = Req.
-

Or using the related functions:

-
-
-
Scheme = cowboy_req:scheme(Req),
-Host = cowboy_req:host(Req),
-Port = cowboy_req:port(Req),
-Path = cowboy_req:path(Req).
-Qs = cowboy_req:qs(Req).
-

The scheme and host are lowercased case insensitive binary -strings. The port is an integer representing the port number. -The path and query string are case sensitive binary strings.

-

Cowboy defines only the <<"http">> and <<"https">> schemes. -They are chosen so that the scheme will only be <<"https">> -for requests on secure HTTP/1.1 or HTTP/2 connections.

-

The effective request URI itself can be reconstructed with -the cowboy_req:uri/1,2 function. By default, an absolute -URI is returned:

-
-
+

The effective request URI itself can be reconstructed with the cowboy_req:uri/1,2 function. By default, an absolute URI is returned:

+
-
%% scheme://host[:port]/path[?qs]
-URI = cowboy_req:uri(Req).
-

Options are available to either disable or replace some -or all of the components. Various URIs or URI formats can -be generated this way, including the origin form:

-
-
-
%% /path[?qs]
-URI = cowboy_req:uri(Req, #{host => undefined}).
-

The protocol relative form:

-
-
-
%% //host[:port]/path[?qs]
-URI = cowboy_req:uri(Req, #{scheme => undefined}).
-

The absolute URI without a query string:

-
-
-
URI = cowboy_req:uri(Req, #{qs => undefined}).
-

A different host:

-
-
-
URI = cowboy_req:uri(Req, #{host => <<"example.org">>}).
-

And any other combination.

-
-
-
+
URI = cowboy_req:uri(Req, #{host => <<"example.org">>}).
+
+

And any other combination.

Bindings

-
-

Bindings are the host and path components that you chose -to extract when defining the routes of your application. -They are only available after the routing.

-

Cowboy provides functions to retrieve one or all bindings.

-

To retrieve a single value:

-
-
-
Value = cowboy_req:binding(userid, Req).
-

When attempting to retrieve a value that was not bound, -undefined will be returned. A different default value -can be provided:

-
-
-
Value = cowboy_req:binding(userid, Req, 42).
-

To retrieve everything that was bound:

-
-
-
Bindings = cowboy_req:bindings(Req).
-

They are returned as a map, with keys being atoms.

-

The Cowboy router also allows you to capture many host -or path segments at once using the ... qualifier.

-

To retrieve the segments captured from the host name:

-
-
-
HostInfo = cowboy_req:host_info(Req).
-

And the path segments:

-
-
-
PathInfo = cowboy_req:path_info(Req).
-

Cowboy will return undefined if ... was not used -in the route.

-
- -
+
PathInfo = cowboy_req:path_info(Req).
+
+

Cowboy will return undefined if ... was not used in the route.

Query parameters

-
-

Cowboy provides two functions to access query parameters. -You can use the first to get the entire list of parameters.

-
-
-
QsVals = cowboy_req:parse_qs(Req),
-{_, Lang} = lists:keyfind(<<"lang">>, 1, QsVals).
-

Cowboy will only parse the query string, and not do any -transformation. This function may therefore return duplicates, -or parameter names without an associated value. The order of -the list returned is undefined.

-

When a query string is key=1&key=2, the list returned will -contain two parameters of name key.

-

The same is true when trying to use the PHP-style suffix []. -When a query string is key[]=1&key[]=2, the list returned will -contain two parameters of name key[].

-

When a query string is simply key, Cowboy will return the -list [{<<"key">>, true}], using true to indicate that the -parameter key was defined, but with no value.

-

The second function Cowboy provides allows you to match out -only the parameters you are interested in, and at the same -time do any post processing you require using constraints. -This function returns a map.

-
-
-
#{id := ID, lang := Lang} = cowboy_req:match_qs([id, lang], Req).
-

Constraints can be applied automatically. The following -snippet will crash when the id parameter is not an integer, -or when the lang parameter is empty. At the same time, the -value for id will be converted to an integer term:

-
-
-
QsMap = cowboy_req:match_qs([{id, int}, {lang, nonempty}], Req).
-

A default value may also be provided. The default will be used -if the lang key is not found. It will not be used if -the key is found but has an empty value.

-
-
-
#{lang := Lang} = cowboy_req:match_qs([{lang, [], <<"en-US">>}], Req).
-

If no default is provided and the value is missing, the -query string is deemed invalid and the process will crash.

-

When the query string is key=1&key=2, the value for key -will be the list [1, 2]. Parameter names do not need to -include the PHP-style suffix. Constraints may be used to -ensure that only one value was passed through.

-
- -
+
#{lang := Lang} = cowboy_req:match_qs([{lang, [], <<"en-US">>}], Req).
+
+

If no default is provided and the value is missing, the query string is deemed invalid and the process will crash.

+

When the query string is key=1&key=2, the value for key will be the list [1, 2]. Parameter names do not need to include the PHP-style suffix. Constraints may be used to ensure that only one value was passed through.

Headers

-
-

Header values can be retrieved either as a binary string -or parsed into a more meaningful representation.

-

The get the raw value:

-
-
-
HeaderVal = cowboy_req:header(<<"content-type">>, Req).
-

Cowboy expects all header names to be provided as lowercase -binary strings. This is true for both requests and responses, -regardless of the underlying protocol.

-

When the header is missing from the request, undefined -will be returned. A different default can be provided:

-
-
-
HeaderVal = cowboy_req:header(<<"content-type">>, Req, <<"text/plain">>).
-

All headers can be retrieved at once, either directly:

-
-
-
#{headers := AllHeaders} = Req.
-

Or using a function:

-
-
-
AllHeaders = cowboy_req:headers(Req).
-

Cowboy provides equivalent functions to parse individual -headers. There is no function to parse all headers at once.

-

To parse a specific header:

-
-
-
ParsedVal = cowboy_req:parse_header(<<"content-type">>, Req).
-

An exception will be thrown if it doesn’t know how to parse the -given header, or if the value is invalid. The list of known headers -and default values can be found in the manual.

-

When the header is missing, undefined is returned. You can -change the default value. Note that it should be the parsed value -directly:

-
-
-
ParsedVal = cowboy_req:parse_header(<<"content-type">>, Req,
-    {<<"text">>, <<"plain">>, []}).
-
- -
+
ParsedVal = cowboy_req:parse_header(<<"content-type">>, Req,
+    {<<"text">>, <<"plain">>, []}).
+

Peer

-
-

The peer address and port number for the connection can be -retrieved either directly or using a function.

-

To retrieve the peer directly:

-
-
-
#{peer := {IP, Port}} = Req.
-

And using a function:

-
-
-
{IP, Port} = cowboy_req:peer(Req).
-

Note that the peer corresponds to the remote end of the -connection to the server, which may or may not be the -client itself. It may also be a proxy or a gateway.

-
- +
{IP, Port} = cowboy_req:peer(Req).
+ +

Note that the peer corresponds to the remote end of the connection to the server, which may or may not be the client itself. It may also be a proxy or a gateway.

+ diff --git a/docs/en/cowboy/2.3/guide/req_body/index.html b/docs/en/cowboy/2.3/guide/req_body/index.html index 7db337da..a127f6f2 100644 --- a/docs/en/cowboy/2.3/guide/req_body/index.html +++ b/docs/en/cowboy/2.3/guide/req_body/index.html @@ -62,144 +62,93 @@

Reading the request body

-

The request body can be read using the Req object.

-

Cowboy will not attempt to read the body until requested. -You need to call the body reading functions in order to -retrieve it.

-

Cowboy will not cache the body, it is therefore only -possible to read it once.

-

You are not required to read it, however. If a body is -present and was not read, Cowboy will either cancel or -skip its download, depending on the protocol.

-

Cowboy provides functions for reading the body raw, -and read and parse form urlencoded or multipart bodies. -The latter is covered in its own chapter.

-
+

The request body can be read using the Req object.

+

Cowboy will not attempt to read the body until requested. You need to call the body reading functions in order to retrieve it.

+

Cowboy will not cache the body, it is therefore only possible to read it once.

+

You are not required to read it, however. If a body is present and was not read, Cowboy will either cancel or skip its download, depending on the protocol.

+

Cowboy provides functions for reading the body raw, and read and parse form urlencoded or multipart bodies. The latter is covered in its own chapter.

Request body presence

-
-

Not all requests come with a body. You can check for -the presence of a request body with this function:

-
-
-
cowboy_req:has_body(Req).
-

It returns true if there is a body; false otherwise.

-

In practice, this function is rarely used. When the -method is POST, PUT or PATCH, the request body -is often required by the application, which should -just attempt to read it directly.

-
-
-
+
cowboy_req:has_body(Req).
+
+

It returns true if there is a body; false otherwise.

+

In practice, this function is rarely used. When the method is POST, PUT or PATCH, the request body is often required by the application, which should just attempt to read it directly.

Request body length

-
-

You can obtain the length of the body:

-
-
-
Length = cowboy_req:body_length(Req).
-

Note that the length may not be known in advance. In -that case undefined will be returned. This can happen -with HTTP/1.1’s chunked transfer-encoding, or HTTP/2 -when no content-length was provided.

-

Cowboy will update the body length in the Req object -once the body has been read completely. A length will -always be returned when attempting to call this function -after reading the body completely.

-
- -
+
Length = cowboy_req:body_length(Req).
+
+

Note that the length may not be known in advance. In that case undefined will be returned. This can happen with HTTP/1.1's chunked transfer-encoding, or HTTP/2 when no content-length was provided.

+

Cowboy will update the body length in the Req object once the body has been read completely. A length will always be returned when attempting to call this function after reading the body completely.

Reading the body

-
-

You can read the entire body with one function call:

-
-
-
{ok, Data, Req} = cowboy_req:read_body(Req0).
-

Cowboy returns an ok tuple when the body has been -read fully.

-

By default, Cowboy will attempt to read up to 8MB -of data, for up to 15 seconds. The call will return -once Cowboy has read at least 8MB of data, or at -the end of the 15 seconds period.

-

These values can be customized. For example, to read -only up to 1MB for up to 5 seconds:

-
-
-
{ok, Data, Req} = cowboy_req:read_body(Req0,
-    #{length => 1000000, period => 5000}).
-

You may also disable the length limit:

-
-
-
{ok, Data, Req} = cowboy_req:read_body(Req0, #{length => infinity}).
-

This makes the function wait 15 seconds and return with -whatever arrived during that period. This is not -recommended for public facing applications.

-

These two options can effectively be used to control -the rate of transmission of the request body.

-
- -
+
{ok, Data, Req} = cowboy_req:read_body(Req0, #{length => infinity}).
+
+

This makes the function wait 15 seconds and return with whatever arrived during that period. This is not recommended for public facing applications.

+

These two options can effectively be used to control the rate of transmission of the request body.

Streaming the body

-
-

When the body is too large, the first call will return -a more tuple instead of ok. You can call the -function again to read more of the body, reading -it one chunk at a time.

-
-
-
read_body_to_console(Req0) ->
-    case cowboy_req:read_body(Req0) of
-        {ok, Data, Req} ->
-            io:format("~s", [Data]),
-            Req;
-        {more, Data, Req} ->
-            io:format("~s", [Data]),
-            read_body_to_console(Req)
-    end.
-

The length and period options can also be used. -They need to be passed for every call.

-
- -
+
read_body_to_console(Req0) ->
+    case cowboy_req:read_body(Req0) of
+        {ok, Data, Req} ->
+            io:format("~s", [Data]),
+            Req;
+        {more, Data, Req} ->
+            io:format("~s", [Data]),
+            read_body_to_console(Req)
+    end.
+
+

The length and period options can also be used. They need to be passed for every call.

Reading a form urlencoded body

-
-

Cowboy provides a convenient function for reading and -parsing bodies sent as application/x-www-form-urlencoded.

-
-
-
{ok, KeyValues, Req} = cowboy_req:read_urlencoded_body(Req0).
-

This function returns a list of key/values, exactly like -the function cowboy_req:parse_qs/1.

-

The defaults for this function are different. Cowboy will -read for up to 64KB and up to 5 seconds. They can be modified:

-
-
-
{ok, KeyValues, Req} = cowboy_req:read_urlencoded_body(Req0,
-    #{length => 4096, period => 3000}).
-
- +
{ok, KeyValues, Req} = cowboy_req:read_urlencoded_body(Req0,
+    #{length => 4096, period => 3000}).
+ + diff --git a/docs/en/cowboy/2.3/guide/resource_design/index.html b/docs/en/cowboy/2.3/guide/resource_design/index.html index be567d98..699ebc56 100644 --- a/docs/en/cowboy/2.3/guide/resource_design/index.html +++ b/docs/en/cowboy/2.3/guide/resource_design/index.html @@ -62,213 +62,66 @@

Designing a resource handler

-

This chapter aims to provide you with a list of questions -you must answer in order to write a good resource handler. -It is meant to be usable as a step by step guide.

-
+

This chapter aims to provide you with a list of questions you must answer in order to write a good resource handler. It is meant to be usable as a step by step guide.

The service

-
-

Can the service become unavailable, and when it does, can -we detect it? For example, database connectivity problems -may be detected early. We may also have planned outages -of all or parts of the system. Implement the -service_available callback.

-

What HTTP methods does the service implement? Do we need -more than the standard OPTIONS, HEAD, GET, PUT, POST, -PATCH and DELETE? Are we not using one of those at all? -Implement the known_methods callback.

-
-
-
+

Can the service become unavailable, and when it does, can we detect it? For example, database connectivity problems may be detected early. We may also have planned outages of all or parts of the system. Implement the service_available callback.

+

What HTTP methods does the service implement? Do we need more than the standard OPTIONS, HEAD, GET, PUT, POST, PATCH and DELETE? Are we not using one of those at all? Implement the known_methods callback.

Type of resource handler

-
-

Am I writing a handler for a collection of resources, -or for a single resource?

-

The semantics for each of these are quite different. -You should not mix collection and single resource in -the same handler.

-
-
-
+

Am I writing a handler for a collection of resources, or for a single resource?

+

The semantics for each of these are quite different. You should not mix collection and single resource in the same handler.

Collection handler

-
-

Skip this section if you are not doing a collection.

-

Is the collection hardcoded or dynamic? For example, -if you use the route /users for the collection of -users then the collection is hardcoded; if you use -/forums/:category for the collection of threads -then it isn’t. When the collection is hardcoded you -can safely assume the resource always exists.

-

What methods should I implement?

-

OPTIONS is used to get some information about the -collection. It is recommended to allow it even if you -do not implement it, as Cowboy has a default -implementation built-in.

-

HEAD and GET are used to retrieve the collection. -If you allow GET, also allow HEAD as there’s no extra -work required to make it work.

-

POST is used to create a new resource inside the -collection. Creating a resource by using POST on -the collection is useful when resources may be -created before knowing their URI, usually because -parts of it are generated dynamically. A common -case is some kind of auto incremented integer -identifier.

-

The next methods are more rarely allowed.

-

PUT is used to create a new collection (when -the collection isn’t hardcoded), or replace -the entire collection.

-

DELETE is used to delete the entire collection.

-

PATCH is used to modify the collection using -instructions given in the request body. A PATCH -operation is atomic. The PATCH operation may -be used for such things as reordering; adding, -modifying or deleting parts of the collection.

-
-
-
+

Skip this section if you are not doing a collection.

+

Is the collection hardcoded or dynamic? For example, if you use the route /users for the collection of users then the collection is hardcoded; if you use /forums/:category for the collection of threads then it isn't. When the collection is hardcoded you can safely assume the resource always exists.

+

What methods should I implement?

+

OPTIONS is used to get some information about the collection. It is recommended to allow it even if you do not implement it, as Cowboy has a default implementation built-in.

+

HEAD and GET are used to retrieve the collection. If you allow GET, also allow HEAD as there's no extra work required to make it work.

+

POST is used to create a new resource inside the collection. Creating a resource by using POST on the collection is useful when resources may be created before knowing their URI, usually because parts of it are generated dynamically. A common case is some kind of auto incremented integer identifier.

+

The next methods are more rarely allowed.

+

PUT is used to create a new collection (when the collection isn't hardcoded), or replace the entire collection.

+

DELETE is used to delete the entire collection.

+

PATCH is used to modify the collection using instructions given in the request body. A PATCH operation is atomic. The PATCH operation may be used for such things as reordering; adding, modifying or deleting parts of the collection.

Single resource handler

-
-

Skip this section if you are doing a collection.

-

What methods should I implement?

-

OPTIONS is used to get some information about the -resource. It is recommended to allow it even if you -do not implement it, as Cowboy has a default -implementation built-in.

-

HEAD and GET are used to retrieve the resource. -If you allow GET, also allow HEAD as there’s no extra -work required to make it work.

-

POST is used to update the resource.

-

PUT is used to create a new resource (when it doesn’t -already exist) or replace the resource.

-

DELETE is used to delete the resource.

-

PATCH is used to modify the resource using -instructions given in the request body. A PATCH -operation is atomic. The PATCH operation may -be used for adding, removing or modifying specific -values in the resource.

-
-
-
+

Skip this section if you are doing a collection.

+

What methods should I implement?

+

OPTIONS is used to get some information about the resource. It is recommended to allow it even if you do not implement it, as Cowboy has a default implementation built-in.

+

HEAD and GET are used to retrieve the resource. If you allow GET, also allow HEAD as there's no extra work required to make it work.

+

POST is used to update the resource.

+

PUT is used to create a new resource (when it doesn't already exist) or replace the resource.

+

DELETE is used to delete the resource.

+

PATCH is used to modify the resource using instructions given in the request body. A PATCH operation is atomic. The PATCH operation may be used for adding, removing or modifying specific values in the resource.

The resource

-
-

Following the above discussion, implement the -allowed_methods callback.

-

Does the resource always exist? If it may not, implement -the resource_exists callback.

-

Do I need to authenticate the client before they can -access the resource? What authentication mechanisms -should I provide? This may include form-based, token-based -(in the URL or a cookie), HTTP basic, HTTP digest, -SSL certificate or any other form of authentication. -Implement the is_authorized callback.

-

Do I need fine-grained access control? How do I determine -that they are authorized access? Handle that in your -is_authorized callback.

-

Can access to a resource be forbidden regardless of access -being authorized? A simple example of that is censorship -of a resource. Implement the forbidden callback.

-

Are there any constraints on the length of the resource URI? -For example, the URI may be used as a key in storage and may -have a limit in length. Implement uri_too_long.

-
-
-
+

Following the above discussion, implement the allowed_methods callback.

+

Does the resource always exist? If it may not, implement the resource_exists callback.

+

Do I need to authenticate the client before they can access the resource? What authentication mechanisms should I provide? This may include form-based, token-based (in the URL or a cookie), HTTP basic, HTTP digest, SSL certificate or any other form of authentication. Implement the is_authorized callback.

+

Do I need fine-grained access control? How do I determine that they are authorized access? Handle that in your is_authorized callback.

+

Can access to a resource be forbidden regardless of access being authorized? A simple example of that is censorship of a resource. Implement the forbidden callback.

+

Are there any constraints on the length of the resource URI? For example, the URI may be used as a key in storage and may have a limit in length. Implement uri_too_long.

Representations

-
-

What media types do I provide? If text based, what charsets -are provided? What languages do I provide?

-

Implement the mandatory content_types_provided. Prefix -the callbacks with to_ for clarity. For example, to_html -or to_text.

-

Implement the languages_provided or charsets_provided -callbacks if applicable.

-

Is there any other header that may make the representation -of the resource vary? Implement the variances callback.

-

Depending on your choices for caching content, you may -want to implement one or more of the generate_etag, -last_modified and expires callbacks.

-

Do I want the user or user agent to actively choose a -representation available? Send a list of available -representations in the response body and implement -the multiple_choices callback.

-
-
-
+

What media types do I provide? If text based, what charsets are provided? What languages do I provide?

+

Implement the mandatory content_types_provided. Prefix the callbacks with to_ for clarity. For example, to_html or to_text.

+

Implement the languages_provided or charsets_provided callbacks if applicable.

+

Is there any other header that may make the representation of the resource vary? Implement the variances callback.

+

Depending on your choices for caching content, you may want to implement one or more of the generate_etag, last_modified and expires callbacks.

+

Do I want the user or user agent to actively choose a representation available? Send a list of available representations in the response body and implement the multiple_choices callback.

Redirections

-
-

Do I need to keep track of what resources were deleted? -For example, you may have a mechanism where moving a -resource leaves a redirect link to its new location. -Implement the previously_existed callback.

-

Was the resource moved, and is the move temporary? If -it is explicitly temporary, for example due to maintenance, -implement the moved_temporarily callback. Otherwise, -implement the moved_permanently callback.

-
-
-
+

Do I need to keep track of what resources were deleted? For example, you may have a mechanism where moving a resource leaves a redirect link to its new location. Implement the previously_existed callback.

+

Was the resource moved, and is the move temporary? If it is explicitly temporary, for example due to maintenance, implement the moved_temporarily callback. Otherwise, implement the moved_permanently callback.

The request

-
-

Do you need to read the query string? Individual headers? -Implement malformed_request and do all the parsing and -validation in this function. Note that the body should not -be read at this point.

-

May there be a request body? Will I know its size? -What’s the maximum size of the request body I’m willing -to accept? Implement valid_entity_length.

-

Finally, take a look at the sections corresponding to the -methods you are implementing.

-
-
-
+

Do you need to read the query string? Individual headers? Implement malformed_request and do all the parsing and validation in this function. Note that the body should not be read at this point.

+

May there be a request body? Will I know its size? What's the maximum size of the request body I'm willing to accept? Implement valid_entity_length.

+

Finally, take a look at the sections corresponding to the methods you are implementing.

OPTIONS method

-
-

Cowboy by default will send back a list of allowed methods. -Do I need to add more information to the response? Implement -the options method.

-
-
-
+

Cowboy by default will send back a list of allowed methods. Do I need to add more information to the response? Implement the options method.

GET and HEAD methods

-
-

If you implement the methods GET and/or HEAD, you must -implement one ProvideResource callback for each -content-type returned by the content_types_provided -callback.

-
-
-
-

PUT, POST and PATCH methods

-
-

If you implement the methods PUT, POST and/or PATCH, -you must implement the content_types_accepted callback, -and one AcceptCallback callback for each content-type -it returns. Prefix the AcceptCallback callback names -with from_ for clarity. For example, from_html or -from_json.

-

Do we want to allow the POST method to create individual -resources directly through their URI (like PUT)? Implement -the allow_missing_post callback. It is recommended to -explicitly use PUT in these cases instead.

-

May there be conflicts when using PUT to create or replace -a resource? Do we want to make sure that two updates around -the same time are not cancelling one another? Implement the -is_conflict callback.

-
-
-
+

If you implement the methods GET and/or HEAD, you must implement one ProvideResource callback for each content-type returned by the content_types_provided callback.

+

PUT, POST and PATCH methods

+

If you implement the methods PUT, POST and/or PATCH, you must implement the content_types_accepted callback, and one AcceptCallback callback for each content-type it returns. Prefix the AcceptCallback callback names with from_ for clarity. For example, from_html or from_json.

+

Do we want to allow the POST method to create individual resources directly through their URI (like PUT)? Implement the allow_missing_post callback. It is recommended to explicitly use PUT in these cases instead.

+

May there be conflicts when using PUT to create or replace a resource? Do we want to make sure that two updates around the same time are not cancelling one another? Implement the is_conflict callback.

DELETE methods

-
-

If you implement the method DELETE, you must implement -the delete_resource callback.

-

When delete_resource returns, is the resource completely -removed from the server, including from any caching service? -If not, and/or if the deletion is asynchronous and we have -no way of knowing it has been completed yet, implement the -delete_completed callback.

-
-
+

If you implement the method DELETE, you must implement the delete_resource callback.

+

When delete_resource returns, is the resource completely removed from the server, including from any caching service? If not, and/or if the deletion is asynchronous and we have no way of knowing it has been completed yet, implement the delete_completed callback.

+ diff --git a/docs/en/cowboy/2.3/guide/resp/index.html b/docs/en/cowboy/2.3/guide/resp/index.html index bc1a04ea..2fb3f064 100644 --- a/docs/en/cowboy/2.3/guide/resp/index.html +++ b/docs/en/cowboy/2.3/guide/resp/index.html @@ -62,373 +62,249 @@

Sending a response

-

The response must be sent using the Req object.

-

Cowboy provides two different ways of sending responses: -either directly or by streaming the body. Response headers -and body may be set in advance. The response is sent as -soon as one of the reply or stream reply function is -called.

-

Cowboy also provides a simplified interface for sending -files. It can also send only specific parts of a file.

-

While only one response is allowed for every request, -HTTP/2 introduced a mechanism that allows the server -to push additional resources related to the response. -This chapter also describes how this feature works in -Cowboy.

-
+

The response must be sent using the Req object.

+

Cowboy provides two different ways of sending responses: either directly or by streaming the body. Response headers and body may be set in advance. The response is sent as soon as one of the reply or stream reply function is called.

+

Cowboy also provides a simplified interface for sending files. It can also send only specific parts of a file.

+

While only one response is allowed for every request, HTTP/2 introduced a mechanism that allows the server to push additional resources related to the response. This chapter also describes how this feature works in Cowboy.

Reply

-
-

Cowboy provides three functions for sending the entire reply, -depending on whether you need to set headers and body. In all -cases, Cowboy will add any headers required by the protocol -(for example the date header will always be sent).

-

When you need to set only the status code, -use cowboy_req:reply/2:

-
-
-
Req = cowboy_req:reply(200, Req0).
-

When you need to set response headers at the same time, -use cowboy_req:reply/3:

-
-
-
Req = cowboy_req:reply(303, #{
-    <<"location">> => <<"https://ninenines.eu">>
-}, Req0).
-

Note that the header name must always be a lowercase -binary.

-

When you also need to set the response body, -use cowboy_req:reply/4:

-
-
-
Req = cowboy_req:reply(200, #{
-    <<"content-type">> => <<"text/plain">>
-}, "Hello world!", Req0).
-

You should always set the content-type header when the -response has a body. There is however no need to set -the content-length header; Cowboy does it automatically.

-

The response body and the header values must be either -a binary or an iolist. An iolist is a list containing -binaries, characters, strings or other iolists. This -allows you to build a response from different parts -without having to do any concatenation:

-
-
-
Title = "Hello world!",
-Body = <<"Hats off!">>,
-Req = cowboy_req:reply(200, #{
-    <<"content-type">> => <<"text/html">>
-}, ["<html><head><title>", Title, "</title></head>",
-    "<body><p>", Body, "</p></body></html>"], Req0).
-

This method of building responses is more efficient than -concatenating. Behind the scenes, each element of the list -is simply a pointer, and those pointers are used directly -when writing to the socket.

-
-
-
+
Title = "Hello world!",
+Body = <<"Hats off!">>,
+Req = cowboy_req:reply(200, #{
+    <<"content-type">> => <<"text/html">>
+}, ["<html><head><title>", Title, "</title></head>",
+    "<body><p>", Body, "</p></body></html>"], Req0).
+
+

This method of building responses is more efficient than concatenating. Behind the scenes, each element of the list is simply a pointer, and those pointers are used directly when writing to the socket.

Stream reply

-
-

Cowboy provides two functions for initiating a response, -and an additional function for streaming the response body. -Cowboy will add any required headers to the response.

-

When you need to set only the status code, -use cowboy_req:stream_reply/2:

-
-
+

When you need to set only the status code, use cowboy_req:stream_reply/2:

+
-
Req = cowboy_req:stream_reply(200, Req0),
-
-cowboy_req:stream_body("Hello...", nofin, Req),
-cowboy_req:stream_body("chunked...", nofin, Req),
-cowboy_req:stream_body("world!!", fin, Req).
-

The second argument to cowboy_req:stream_body/3 indicates -whether this data terminates the body. Use fin for the -final flag, and nofin otherwise.

-

This snippet does not set a content-type header. This is -not recommended. All responses with a body should have -a content-type. The header can be set beforehand, or -using the cowboy_req:stream_reply/3:

-
-
-
Req = cowboy_req:stream_reply(200, #{
-    <<"content-type">> => <<"text/html">>
-}, Req0),
-
-cowboy_req:stream_body("<html><head>Hello world!</head>", nofin, Req),
-cowboy_req:stream_body("<body><p>Hats off!</p></body></html>", fin, Req).
-

HTTP provides a few different ways to stream response bodies. -Cowboy will select the most appropriate one based on the HTTP -version and the request and response headers.

-

While not required by any means, it is recommended that you -set the content-length header in the response if you know it -in advance. This will ensure that the best response method -is selected and help clients understand when the response -is fully received.

-

Cowboy also provides a function to send response trailers. -Response trailers are semantically equivalent to the headers -you send in the response, only they are sent at the end. -This is especially useful to attach information to the -response that could not be generated until the response -body was fully generated.

-

Trailer fields must be listed in the trailer header. Any -field not listed might be dropped by the client or an intermediary.

-
-
-
Req = cowboy_req:stream_reply(200, #{
-    <<"content-type">> => <<"text/html">>,
-    <<"trailer">> => <<"expires, content-md5">>
-}, Req0),
-
-cowboy_req:stream_body("<html><head>Hello world!</head>", nofin, Req),
-cowboy_req:stream_body("<body><p>Hats off!</p></body></html>", nofin, Req),
-
-cowboy_req:stream_trailers(#{
-    <<"expires">> => <<"Sun, 10 Dec 2017 19:13:47 GMT">>,
-    <<"content-md5">> => <<"c6081d20ff41a42ce17048ed1c0345e2">>
-}, Req).
-

The stream ends with trailers. It is no longer possible to -send data after sending trailers. You cannot send trailers -after setting the fin flag when streaming the body.

-
-
-
+
Req = cowboy_req:stream_reply(200, #{
+    <<"content-type">> => <<"text/html">>,
+    <<"trailer">> => <<"expires, content-md5">>
+}, Req0),
+
+cowboy_req:stream_body("<html><head>Hello world!</head>", nofin, Req),
+cowboy_req:stream_body("<body><p>Hats off!</p></body></html>", nofin, Req),
+
+cowboy_req:stream_trailers(#{
+    <<"expires">> => <<"Sun, 10 Dec 2017 19:13:47 GMT">>,
+    <<"content-md5">> => <<"c6081d20ff41a42ce17048ed1c0345e2">>
+}, Req).
+
+

The stream ends with trailers. It is no longer possible to send data after sending trailers. You cannot send trailers after setting the fin flag when streaming the body.

Preset response headers

-
-

Cowboy provides functions to set response headers without -immediately sending them. They are stored in the Req object -and sent as part of the response when a reply function is -called.

-

To set response headers:

-
-
-
Req = cowboy_req:set_resp_header(<<"allow">>, "GET", Req0).
-

Header names must be a lowercase binary.

-

Do not use this function for setting cookies. Refer to -the Cookies chapter for more information.

-

To check if a response header has already been set:

-
-
-
cowboy_req:has_resp_header(<<"allow">>, Req).
-

It returns true if the header was set, false otherwise.

-

To delete a response header that was set previously:

-
-
-
Req = cowboy_req:delete_resp_header(<<"allow">>, Req0).
-
- -
+
Req = cowboy_req:delete_resp_header(<<"allow">>, Req0).
+

Overriding headers

-
-

As Cowboy provides different ways of setting response -headers and body, clashes may occur, so it’s important -to understand what happens when a header is set twice.

-

Headers come from five different origins:

-
    -
  • -

    -Protocol-specific headers (for example HTTP/1.1’s connection header) -

    +

    As Cowboy provides different ways of setting response headers and body, clashes may occur, so it's important to understand what happens when a header is set twice.

    +

    Headers come from five different origins:

    +
    • Protocol-specific headers (for example HTTP/1.1's connection header)
      • -
    • -

      -Other required headers (for example the date header) -

      +
    • Other required headers (for example the date header)
      • -
    • -

      -Preset headers -

      +
    • Preset headers
      • -
    • -

      -Headers given to the reply function -

      +
    • Headers given to the reply function
      • -
    • -

      -Set-cookie headers -

      +
    • Set-cookie headers
      • -
-

Cowboy does not allow overriding protocol-specific headers.

-

Set-cookie headers will always be appended at the end of -the list of headers before sending the response.

-

Headers given to the reply function will always override -preset headers and required headers. If a header is found -in two or three of these, then the one in the reply function -is picked and the others are dropped.

-

Similarly, preset headers will always override required -headers.

-

To illustrate, look at the following snippet. Cowboy by -default sends the server header with the value "Cowboy". -We can override it:

-
-
-
Req = cowboy_req:reply(200, #{
-    <<"server">> => <<"yaws">>
-}, Req0).
-
- -
+
Req = cowboy_req:reply(200, #{
+    <<"server">> => <<"yaws">>
+}, Req0).
+

Preset response body

-
-

Cowboy provides functions to set the response body without -immediately sending it. It is stored in the Req object and -sent when the reply function is called.

-

To set the response body:

-
-
-
Req = cowboy_req:set_resp_body("Hello world!", Req0).
-

To check if a response body has already been set:

-
-
+ +

To check if a response body has already been set:

+
-
cowboy_req:has_resp_body(Req).
-

It returns true if the body was set and is non-empty, -false otherwise.

-

The preset response body is only sent if the reply function -used is cowboy_req:reply/2 or cowboy_req:reply/3.

-
-
-
+
cowboy_req:has_resp_body(Req).
+
+

It returns true if the body was set and is non-empty, false otherwise.

+ + + +

The preset response body is only sent if the reply function used is cowboy_req:reply/2 or cowboy_req:reply/3.

Sending files

-
-

Cowboy provides a shortcut for sending files. When -using cowboy_req:reply/4, or when presetting the -response header, you can give a sendfile tuple to -Cowboy:

-
-
-
{sendfile, Offset, Length, Filename}
-

Depending on the values for Offset or Length, the -entire file may be sent, or just a part of it.

-

The length is required even for sending the entire file. -Cowboy sends it in the content-length header.

-

To send a file while replying:

-
-
-
Req = cowboy_req:reply(200, #{
-    <<"content-type">> => "image/png"
-}, {sendfile, 0, 12345, "path/to/logo.png"}, Req0).
-
- -
+
Req = cowboy_req:reply(200, #{
+    <<"content-type">> => "image/png"
+}, {sendfile, 0, 12345, "path/to/logo.png"}, Req0).
+
+ + + + + + + + +

Informational responses

-
-

Cowboy allows you to send informational responses.

-

Informational responses are responses that have a status -code between 100 and 199. Any number can be sent before -the proper response. Sending an informational response -does not change the behavior of the proper response, and -clients are expected to ignore any informational response -they do not understand.

-

The following snippet sends a 103 informational response -with some headers that are expected to be in the final -response.

-
-
-
Req = cowboy_req:inform(103, #{
-    <<"link">> => <<"</style.css>; rel=preload; as=style, </script.js>; rel=preload; as=script">>
-}, Req0).
-
- -
+
Req = cowboy_req:inform(103, #{
+    <<"link">> => <<"</style.css>; rel=preload; as=style, </script.js>; rel=preload; as=script">>
+}, Req0).
+

Push

-
-

The HTTP/2 protocol introduced the ability to push resources -related to the one sent in the response. Cowboy provides two -functions for that purpose: cowboy_req:push/3,4.

-

Push is only available for HTTP/2. Cowboy will automatically -ignore push requests if the protocol doesn’t support it.

-

The push function must be called before any of the reply -functions. Doing otherwise will result in a crash.

-

To push a resource, you need to provide the same information -as a client performing a request would. This includes the -HTTP method, the URI and any necessary request headers.

-

Cowboy by default only requires you to give the path to -the resource and the request headers. The rest of the URI -is taken from the current request (excluding the query -string, set to empty) and the method is GET by default.

-

The following snippet pushes a CSS file that is linked to -in the response:

-
-
-
cowboy_req:push("/static/style.css", #{
-    <<"accept">> => <<"text/css">>
-}, Req0),
-Req = cowboy_req:reply(200, #{
-    <<"content-type">> => <<"text/html">>
-}, ["<html><head><title>My web page</title>",
-    "<link rel='stylesheet' type='text/css' href='/static/style.css'>",
-    "<body><p>Welcome to Erlang!</p></body></html>"], Req0).
-

To override the method, scheme, host, port or query string, -simply pass in a fourth argument. The following snippet -uses a different host name:

-
-
-
cowboy_req:push("/static/style.css", #{
-    <<"accept">> => <<"text/css">>
-}, #{host => <<"cdn.example.org">>}, Req),
-

Pushed resources don’t have to be files. As long as the push -request is cacheable, safe and does not include a body, the -resource can be pushed.

-

Under the hood, Cowboy handles pushed requests the same as -normal requests: a different process is created which will -ultimately send a response to the client.

-
- +
cowboy_req:push("/static/style.css", #{
+    <<"accept">> => <<"text/css">>
+}, #{host => <<"cdn.example.org">>}, Req),
+ +

Pushed resources don't have to be files. As long as the push request is cacheable, safe and does not include a body, the resource can be pushed.

+

Under the hood, Cowboy handles pushed requests the same as normal requests: a different process is created which will ultimately send a response to the client.

+ diff --git a/docs/en/cowboy/2.3/guide/rest_flowcharts/index.html b/docs/en/cowboy/2.3/guide/rest_flowcharts/index.html index 7951c237..698e74db 100644 --- a/docs/en/cowboy/2.3/guide/rest_flowcharts/index.html +++ b/docs/en/cowboy/2.3/guide/rest_flowcharts/index.html @@ -62,244 +62,64 @@

REST flowcharts

-

This chapter will explain the REST handler state machine through -a number of different diagrams.

-

There are four main paths that requests may follow. One for the -method OPTIONS; one for the methods GET and HEAD; one for the -methods PUT, POST and PATCH; and one for the method DELETE.

-

All paths start with the "Start" diagram, and all paths excluding -the OPTIONS path go through the "Content negotiation" diagram -and optionally the "Conditional requests" diagram if the resource -exists.

-

The red squares refer to another diagram. The light green squares -indicate a response. Other squares may be either a callback or a -question answered by Cowboy itself. Green arrows tend to indicate -the default behavior if the callback is undefined.

-
+

This chapter will explain the REST handler state machine through a number of different diagrams.

+

There are four main paths that requests may follow. One for the method OPTIONS; one for the methods GET and HEAD; one for the methods PUT, POST and PATCH; and one for the method DELETE.

+

All paths start with the "Start" diagram, and all paths excluding the OPTIONS path go through the "Content negotiation" diagram and optionally the "Conditional requests" diagram if the resource exists.

+

The red squares refer to another diagram. The light green squares indicate a response. Other squares may be either a callback or a question answered by Cowboy itself. Green arrows tend to indicate the default behavior if the callback is undefined.

Start

-
-

All requests start from here.

-
-
-REST starting flowchart -
-
-

A series of callbacks are called in succession to perform -a general checkup of the service, the request line and -request headers.

-

The request body, if any, is not expected to have been -received for any of these steps. It is only processed -at the end of the "PUT, POST and PATCH methods" diagram, -when all conditions have been met.

-

The known_methods and allowed_methods callbacks -return a list of methods. Cowboy then checks if the request -method is in the list, and stops otherwise.

-

The is_authorized callback may be used to check that -access to the resource is authorized. Authentication -may also be performed as needed. When authorization is -denied, the return value from the callback must include -a challenge applicable to the requested resource, which -will be sent back to the client in the www-authenticate -header.

-

This diagram is immediately followed by either the -"OPTIONS method" diagram when the request method is -OPTIONS, or the "Content negotiation" diagram otherwise.

-
-
-
+

All requests start from here.

+REST starting flowchart

A series of callbacks are called in succession to perform a general checkup of the service, the request line and request headers.

+

The request body, if any, is not expected to have been received for any of these steps. It is only processed at the end of the "PUT, POST and PATCH methods" diagram, when all conditions have been met.

+

The known_methods and allowed_methods callbacks return a list of methods. Cowboy then checks if the request method is in the list, and stops otherwise.

+

The is_authorized callback may be used to check that access to the resource is authorized. Authentication may also be performed as needed. When authorization is denied, the return value from the callback must include a challenge applicable to the requested resource, which will be sent back to the client in the www-authenticate header.

+

This diagram is immediately followed by either the "OPTIONS method" diagram when the request method is OPTIONS, or the "Content negotiation" diagram otherwise.

OPTIONS method

-
-

This diagram only applies to OPTIONS requests.

-
-
-REST OPTIONS method flowchart -
-
-

The options callback may be used to add information -about the resource, such as media types or languages -provided; allowed methods; any extra information. A -response body may also be set, although clients should -not be expected to read it.

-

If the options callback is not defined, Cowboy will -send a response containing the list of allowed methods -by default.

-
-
-
+

This diagram only applies to OPTIONS requests.

+REST OPTIONS method flowchart

The options callback may be used to add information about the resource, such as media types or languages provided; allowed methods; any extra information. A response body may also be set, although clients should not be expected to read it.

+

If the options callback is not defined, Cowboy will send a response containing the list of allowed methods by default.

Content negotiation

-
-

This diagram applies to all request methods other than -OPTIONS. It is executed right after the "Start" diagram -is completed.

-
-
-REST content negotiation flowchart -
-
-

The purpose of these steps is to determine an appropriate -representation to be sent back to the client.

-

The request may contain any of the accept header; the -accept-language header; or the accept-charset header. -When present, Cowboy will parse the headers and then -call the corresponding callback to obtain the list -of provided content-type, language or charset for this -resource. It then automatically select the best match -based on the request.

-

If a callback is not defined, Cowboy will select the -content-type, language or charset that the client -prefers.

-

The content_types_provided also returns the name of -a callback for every content-type it accepts. This -callback will only be called at the end of the -"GET and HEAD methods" diagram, when all conditions -have been met.

-

The selected content-type, language and charset are -saved as meta values in the Req object. You should -use the appropriate representation if you set a -response body manually (alongside an error code, -for example).

-

This diagram is immediately followed by -the "GET and HEAD methods" diagram, -the "PUT, POST and PATCH methods" diagram, -or the "DELETE method" diagram, depending on the -method.

-
-
-
+

This diagram applies to all request methods other than OPTIONS. It is executed right after the "Start" diagram is completed.

+REST content negotiation flowchart

The purpose of these steps is to determine an appropriate representation to be sent back to the client.

+

The request may contain any of the accept header; the accept-language header; or the accept-charset header. When present, Cowboy will parse the headers and then call the corresponding callback to obtain the list of provided content-type, language or charset for this resource. It then automatically select the best match based on the request.

+

If a callback is not defined, Cowboy will select the content-type, language or charset that the client prefers.

+

The content_types_provided also returns the name of a callback for every content-type it accepts. This callback will only be called at the end of the "GET and HEAD methods" diagram, when all conditions have been met.

+

The selected content-type, language and charset are saved as meta values in the Req object. You should use the appropriate representation if you set a response body manually (alongside an error code, for example).

+

This diagram is immediately followed by the "GET and HEAD methods" diagram, the "PUT, POST and PATCH methods" diagram, or the "DELETE method" diagram, depending on the method.

GET and HEAD methods

-
-

This diagram only applies to GET and HEAD requests.

-

For a description of the cond step, please see -the "Conditional requests" diagram.

-
-
-REST GET/HEAD methods flowchart -
-
-

When the resource exists, and the conditional steps -succeed, the resource can be retrieved.

-

Cowboy prepares the response by first retrieving -metadata about the representation, then by calling -the ProvideResource callback. This is the callback -you defined for each content-types you returned from -content_types_provided. This callback returns the body -that will be sent back to the client, or a fun if the -body must be streamed.

-

When the resource does not exist, Cowboy will figure out -whether the resource existed previously, and if so whether -it was moved elsewhere in order to redirect the client to -the new URI.

-

The moved_permanently and moved_temporarily callbacks -must return the new location of the resource if it was in -fact moved.

-
-
-
-

PUT, POST and PATCH methods

-
-

This diagram only applies to PUT, POST and PATCH requests.

-

For a description of the cond step, please see -the "Conditional requests" diagram.

-
-
-REST PUT/POST/PATCH methods flowchart -
-
-

When the resource exists, first the conditional steps -are executed. When that succeeds, and the method is PUT, -Cowboy will call the is_conflict callback. This function -can be used to prevent potential race conditions, by locking -the resource for example.

-

Then all three methods reach the content_types_accepted -step that we will describe in a few paragraphs.

-

When the resource does not exist, and the method is PUT, -Cowboy will check for conflicts and then move on to the -content_types_accepted step. For other methods, Cowboy -will figure out whether the resource existed previously, -and if so whether it was moved elsewhere. If the resource -is truly non-existent, the method is POST and the call -for allow_missing_post returns true, then Cowboy will -move on to the content_types_accepted step. Otherwise -the request processing ends there.

-

The moved_permanently and moved_temporarily callbacks -must return the new location of the resource if it was in -fact moved.

-

The content_types_accepted returns a list of -content-types it accepts, but also the name of a callback -for each of them. Cowboy will select the appropriate -callback for processing the request body and call it.

-

This callback may return one of three different return -values.

-

If an error occurred while processing the request body, -it must return false and Cowboy will send an -appropriate error response.

-

If the method is POST, then you may return true with -an URI of where the resource has been created. This is -especially useful for writing handlers for collections.

-

Otherwise, return true to indicate success. Cowboy -will select the appropriate response to be sent depending -on whether a resource has been created, rather than -modified, and on the availability of a location header -or a body in the response.

-
-
-
+

This diagram only applies to GET and HEAD requests.

+

For a description of the cond step, please see the "Conditional requests" diagram.

+REST GET/HEAD methods flowchart

When the resource exists, and the conditional steps succeed, the resource can be retrieved.

+

Cowboy prepares the response by first retrieving metadata about the representation, then by calling the ProvideResource callback. This is the callback you defined for each content-types you returned from content_types_provided. This callback returns the body that will be sent back to the client, or a fun if the body must be streamed.

+

When the resource does not exist, Cowboy will figure out whether the resource existed previously, and if so whether it was moved elsewhere in order to redirect the client to the new URI.

+

The moved_permanently and moved_temporarily callbacks must return the new location of the resource if it was in fact moved.

+

PUT, POST and PATCH methods

+

This diagram only applies to PUT, POST and PATCH requests.

+

For a description of the cond step, please see the "Conditional requests" diagram.

+REST PUT/POST/PATCH methods flowchart

When the resource exists, first the conditional steps are executed. When that succeeds, and the method is PUT, Cowboy will call the is_conflict callback. This function can be used to prevent potential race conditions, by locking the resource for example.

+

Then all three methods reach the content_types_accepted step that we will describe in a few paragraphs.

+

When the resource does not exist, and the method is PUT, Cowboy will check for conflicts and then move on to the content_types_accepted step. For other methods, Cowboy will figure out whether the resource existed previously, and if so whether it was moved elsewhere. If the resource is truly non-existent, the method is POST and the call for allow_missing_post returns true, then Cowboy will move on to the content_types_accepted step. Otherwise the request processing ends there.

+

The moved_permanently and moved_temporarily callbacks must return the new location of the resource if it was in fact moved.

+

The content_types_accepted returns a list of content-types it accepts, but also the name of a callback for each of them. Cowboy will select the appropriate callback for processing the request body and call it.

+

This callback may return one of three different return values.

+

If an error occurred while processing the request body, it must return false and Cowboy will send an appropriate error response.

+

If the method is POST, then you may return true with an URI of where the resource has been created. This is especially useful for writing handlers for collections.

+

Otherwise, return true to indicate success. Cowboy will select the appropriate response to be sent depending on whether a resource has been created, rather than modified, and on the availability of a location header or a body in the response.

DELETE method

-
-

This diagram only applies to DELETE requests.

-

For a description of the cond step, please see -the "Conditional requests" diagram.

-
-
-REST DELETE method flowchart -
-
-

When the resource exists, and the conditional steps -succeed, the resource can be deleted.

-

Deleting the resource is a two steps process. First -the callback delete_resource is executed. Use this -callback to delete the resource.

-

Because the resource may be cached, you must also -delete all cached representations of this resource -in the system. This operation may take a while though, -so you may return before it finished.

-

Cowboy will then call the delete_completed callback. -If you know that the resource has been completely -deleted from your system, including from caches, then -you can return true. If any doubts persist, return -false. Cowboy will assume true by default.

-

To finish, Cowboy checks if you set a response body, -and depending on that, sends the appropriate response.

-

When the resource does not exist, Cowboy will figure out -whether the resource existed previously, and if so whether -it was moved elsewhere in order to redirect the client to -the new URI.

-

The moved_permanently and moved_temporarily callbacks -must return the new location of the resource if it was in -fact moved.

-
-
-
+

This diagram only applies to DELETE requests.

+

For a description of the cond step, please see the "Conditional requests" diagram.

+REST DELETE method flowchart

When the resource exists, and the conditional steps succeed, the resource can be deleted.

+

Deleting the resource is a two steps process. First the callback delete_resource is executed. Use this callback to delete the resource.

+

Because the resource may be cached, you must also delete all cached representations of this resource in the system. This operation may take a while though, so you may return before it finished.

+

Cowboy will then call the delete_completed callback. If you know that the resource has been completely deleted from your system, including from caches, then you can return true. If any doubts persist, return false. Cowboy will assume true by default.

+

To finish, Cowboy checks if you set a response body, and depending on that, sends the appropriate response.

+

When the resource does not exist, Cowboy will figure out whether the resource existed previously, and if so whether it was moved elsewhere in order to redirect the client to the new URI.

+

The moved_permanently and moved_temporarily callbacks must return the new location of the resource if it was in fact moved.

Conditional requests

-
-

This diagram applies to all request methods other than -OPTIONS. It is executed right after the resource_exists -callback, when the resource exists.

-
-
-REST conditional requests flowchart -
-
-

A request becomes conditional when it includes either of -the if-match header; the if-unmodified-since header; the -if-none-match header; or the if-modified-since header.

-

If the condition fails, the request ends immediately -without any retrieval or modification of the resource.

-

The generate_etag and last_modified are called as -needed. Cowboy will only call them once and then cache -the results for subsequent use.

-
-
+

This diagram applies to all request methods other than OPTIONS. It is executed right after the resource_exists callback, when the resource exists.

+REST conditional requests flowchart

A request becomes conditional when it includes either of the if-match header; the if-unmodified-since header; the if-none-match header; or the if-modified-since header.

+

If the condition fails, the request ends immediately without any retrieval or modification of the resource.

+

The generate_etag and last_modified are called as needed. Cowboy will only call them once and then cache the results for subsequent use.

+ diff --git a/docs/en/cowboy/2.3/guide/rest_handlers/index.html b/docs/en/cowboy/2.3/guide/rest_handlers/index.html index 83d1fb46..1d2fe4e6 100644 --- a/docs/en/cowboy/2.3/guide/rest_handlers/index.html +++ b/docs/en/cowboy/2.3/guide/rest_handlers/index.html @@ -62,287 +62,162 @@

REST handlers

-

REST is implemented in Cowboy as a sub protocol. The request -is handled as a state machine with many optional callbacks -describing the resource and modifying the machine’s behavior.

-

The REST handler is the recommended way to handle HTTP requests.

-
+

REST is implemented in Cowboy as a sub protocol. The request is handled as a state machine with many optional callbacks describing the resource and modifying the machine's behavior.

+

The REST handler is the recommended way to handle HTTP requests.

Initialization

-
-

First, the init/2 callback is called. This callback is common -to all handlers. To use REST for the current request, this function -must return a cowboy_rest tuple.

-
-
-
init(Req, State) ->
-    {cowboy_rest, Req, State}.
-

Cowboy will then switch to the REST protocol and start executing -the state machine.

-

After reaching the end of the flowchart, the terminate/3 callback -will be called if it is defined.

-
-
-
+
init(Req, State) ->
+    {cowboy_rest, Req, State}.
+
+

Cowboy will then switch to the REST protocol and start executing the state machine.

+

After reaching the end of the flowchart, the terminate/3 callback will be called if it is defined.

Methods

-
-

The REST component has code for handling the following HTTP methods: -HEAD, GET, POST, PATCH, PUT, DELETE and OPTIONS.

-

Other methods can be accepted, however they have no specific callback -defined for them at this time.

-
- -
+

The REST component has code for handling the following HTTP methods: HEAD, GET, POST, PATCH, PUT, DELETE and OPTIONS.

+

Other methods can be accepted, however they have no specific callback defined for them at this time.

Callbacks

-
-

All callbacks are optional. Some may become mandatory depending -on what other defined callbacks return. The various flowcharts -in the next chapter should be a useful to determine which callbacks -you need.

-

All callbacks take two arguments, the Req object and the State, -and return a three-element tuple of the form {Value, Req, State}.

-

Nearly all callbacks can also return {stop, Req, State} to -stop execution of the request, and -{{switch_handler, Module}, Req, State} or -{{switch_handler, Module, Opts}, Req, State} to switch to -a different handler type. The exceptions are expires -generate_etag, last_modified and variances.

-

The following table summarizes the callbacks and their default values. -If the callback isn’t defined, then the default value will be used. -Please look at the flowcharts to find out the result of each return -value.

-

In the following table, "skip" means the callback is entirely skipped -if it is undefined, moving directly to the next step. Similarly, -"none" means there is no default value for this callback.

-
- --- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - +

All callbacks are optional. Some may become mandatory depending on what other defined callbacks return. The various flowcharts in the next chapter should be a useful to determine which callbacks you need.

+

All callbacks take two arguments, the Req object and the State, and return a three-element tuple of the form {Value, Req, State}.

+

Nearly all callbacks can also return {stop, Req, State} to stop execution of the request, and {{switch_handler, Module}, Req, State} or {{switch_handler, Module, Opts}, Req, State} to switch to a different handler type. The exceptions are expires generate_etag, last_modified and variances.

+

The following table summarizes the callbacks and their default values. If the callback isn't defined, then the default value will be used. Please look at the flowcharts to find out the result of each return value.

+

In the following table, "skip" means the callback is entirely skipped if it is undefined, moving directly to the next step. Similarly, "none" means there is no default value for this callback.

+
Callback name Default value

allowed_methods

[<<"GET">>, <<"HEAD">>, <<"OPTIONS">>]

allow_missing_post

true

charsets_provided

skip

content_types_accepted

none

content_types_provided

[{{ <<"text">>, <<"html">>, '*'}, to_html}]

delete_completed

true

delete_resource

false

expires

undefined

forbidden

false

generate_etag

undefined

is_authorized

true

is_conflict

false

known_methods

[<<"GET">>, <<"HEAD">>, <<"POST">>, <<"PUT">>, <<"PATCH">>, <<"DELETE">>, <<"OPTIONS">>]

languages_provided

skip

last_modified

undefined

malformed_request

false

moved_permanently

false

moved_temporarily

false

multiple_choices

false

options

ok

previously_existed

false

resource_exists

true

service_available

true

uri_too_long

false

+ + + + - - - + + - - - + + - - - + + - -
Callback nameDefault value
allowed_methods[<<"GET">>, <<"HEAD">>, <<"OPTIONS">>]

valid_content_headers

true

allow_missing_posttrue

valid_entity_length

true

charsets_providedskip

variances

[]

content_types_acceptednone
-
-

As you can see, Cowboy tries to move on with the request whenever -possible by using well thought out default values.

-

In addition to these, there can be any number of user-defined -callbacks that are specified through content_types_accepted/2 -and content_types_provided/2. They can take any name, however -it is recommended to use a separate prefix for the callbacks of -each function. For example, from_html and to_html indicate -in the first case that we’re accepting a resource given as HTML, -and in the second case that we send one as HTML.

-
-
-
+content_types_provided +[{{ <<"text">>, <<"html">>, '*'}, to_html}] + +delete_completed +true + +delete_resource +false + +expires +undefined + +forbidden +false + +generate_etag +undefined + +is_authorized +true + +is_conflict +false + +known_methods +[<<"GET">>, <<"HEAD">>, <<"POST">>, <<"PUT">>, <<"PATCH">>, <<"DELETE">>, <<"OPTIONS">>] + +languages_provided +skip + +last_modified +undefined + +malformed_request +false + +moved_permanently +false + +moved_temporarily +false + +multiple_choices +false + +options +ok + +previously_existed +false + +resource_exists +true + +service_available +true + +uri_too_long +false + +valid_content_headers +true + +valid_entity_length +true + +variances +[] + + +

As you can see, Cowboy tries to move on with the request whenever possible by using well thought out default values.

+

In addition to these, there can be any number of user-defined callbacks that are specified through content_types_accepted/2 and content_types_provided/2. They can take any name, however it is recommended to use a separate prefix for the callbacks of each function. For example, from_html and to_html indicate in the first case that we're accepting a resource given as HTML, and in the second case that we send one as HTML.

Meta data

-
-

Cowboy will set informative values to the Req object at various -points of the execution. You can retrieve them by matching the -Req object directly. The values are defined in the following table:

-
- --- - - - - - - - - - - - - - - - - - - - -
Key Details

media_type

The content-type negotiated for the response entity.

language

The language negotiated for the response entity.

charset

The charset negotiated for the response entity.

-
-

They can be used to send a proper body with the response to a -request that used a method other than HEAD or GET.

-
-
-
+

Cowboy will set informative values to the Req object at various points of the execution. You can retrieve them by matching the Req object directly. The values are defined in the following table:

+ + + + + + + + + + + + +
KeyDetails
media_typeThe content-type negotiated for the response entity.
languageThe language negotiated for the response entity.
charsetThe charset negotiated for the response entity.
+

They can be used to send a proper body with the response to a request that used a method other than HEAD or GET.

Response headers

-
-

Cowboy will set response headers automatically over the execution -of the REST code. They are listed in the following table.

-
- --- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Header name Details

content-language

Language used in the response body

content-type

Media type and charset of the response body

etag

Etag of the resource

expires

Expiration date of the resource

last-modified

Last modification date for the resource

location

Relative or absolute URI to the requested resource

vary

List of headers that may change the representation of the resource

-
-
-
+

Cowboy will set response headers automatically over the execution of the REST code. They are listed in the following table.

+ + + + + + + + + + + + + + + + + + + + + + + + +
Header nameDetails
content-languageLanguage used in the response body
content-typeMedia type and charset of the response body
etagEtag of the resource
expiresExpiration date of the resource
last-modifiedLast modification date for the resource
locationRelative or absolute URI to the requested resource
varyList of headers that may change the representation of the resource
+ diff --git a/docs/en/cowboy/2.3/guide/rest_principles/index.html b/docs/en/cowboy/2.3/guide/rest_principles/index.html index 12de886b..78687d10 100644 --- a/docs/en/cowboy/2.3/guide/rest_principles/index.html +++ b/docs/en/cowboy/2.3/guide/rest_principles/index.html @@ -62,153 +62,38 @@

REST principles

-

This chapter will attempt to define the concepts behind REST -and explain what makes a service RESTful.

-

REST is often confused with performing a distinct operation -depending on the HTTP method, while using more than the GET -and POST methods. That’s highly misguided at best.

-

We will first attempt to define REST and will look at what -it means in the context of HTTP and the Web. -For a more in-depth explanation of REST, you can read -Roy T. Fielding’s dissertation -as it does a great job explaining where it comes from and -what it achieves.

-
+

This chapter will attempt to define the concepts behind REST and explain what makes a service RESTful.

+

REST is often confused with performing a distinct operation depending on the HTTP method, while using more than the GET and POST methods. That's highly misguided at best.

+

We will first attempt to define REST and will look at what it means in the context of HTTP and the Web. For a more in-depth explanation of REST, you can read Roy T. Fielding's dissertation as it does a great job explaining where it comes from and what it achieves.

REST architecture

-
-

REST is a client-server architecture. The client and the server -both have a different set of concerns. The server stores and/or -manipulates information and makes it available to the user in -an efficient manner. The client takes that information and -displays it to the user and/or uses it to perform subsequent -requests for information. This separation of concerns allows both -the client and the server to evolve independently as it only -requires that the interface stays the same.

-

REST is stateless. That means the communication between the -client and the server always contains all the information needed -to perform the request. There is no session state in the server, -it is kept entirely on the client’s side. If access to a resource -requires authentication, then the client needs to authenticate -itself with every request.

-

REST is cacheable. The client, the server and any intermediary -components can all cache resources in order to improve performance.

-

REST provides a uniform interface between components. This -simplifies the architecture, as all components follow the same -rules to speak to one another. It also makes it easier to understand -the interactions between the different components of the system. -A number of constraints are required to achieve this. They are -covered in the rest of the chapter.

-

REST is a layered system. Individual components cannot see -beyond the immediate layer with which they are interacting. This -means that a client connecting to an intermediate component, like -a proxy, has no knowledge of what lies beyond. This allows -components to be independent and thus easily replaceable or -extendable.

-

REST optionally provides code on demand. Code may be downloaded -to extend client functionality. This is optional however because -the client may not be able to download or run this code, and so -a REST component cannot rely on it being executed.

-
-
-
+

REST is a client-server architecture. The client and the server both have a different set of concerns. The server stores and/or manipulates information and makes it available to the user in an efficient manner. The client takes that information and displays it to the user and/or uses it to perform subsequent requests for information. This separation of concerns allows both the client and the server to evolve independently as it only requires that the interface stays the same.

+

REST is stateless. That means the communication between the client and the server always contains all the information needed to perform the request. There is no session state in the server, it is kept entirely on the client's side. If access to a resource requires authentication, then the client needs to authenticate itself with every request.

+

REST is cacheable. The client, the server and any intermediary components can all cache resources in order to improve performance.

+

REST provides a uniform interface between components. This simplifies the architecture, as all components follow the same rules to speak to one another. It also makes it easier to understand the interactions between the different components of the system. A number of constraints are required to achieve this. They are covered in the rest of the chapter.

+

REST is a layered system. Individual components cannot see beyond the immediate layer with which they are interacting. This means that a client connecting to an intermediate component, like a proxy, has no knowledge of what lies beyond. This allows components to be independent and thus easily replaceable or extendable.

+

REST optionally provides code on demand. Code may be downloaded to extend client functionality. This is optional however because the client may not be able to download or run this code, and so a REST component cannot rely on it being executed.

Resources and resource identifiers

-
-

A resource is an abstract concept. In a REST system, any information -that can be named may be a resource. This includes documents, images, -a collection of resources and any other information. Any information -that can be the target of an hypertext link can be a resource.

-

A resource is a conceptual mapping to a set of entities. The set of -entities evolves over time; a resource doesn’t. For example, a resource -can map to "users who have logged in this past month" and another -to "all users". At some point in time they may map to the same set of -entities, because all users logged in this past month. But they are -still different resources. Similarly, if nobody logged in recently, -then the first resource may map to the empty set. This resource exists -regardless of the information it maps to.

-

Resources are identified by uniform resource identifiers, also known -as URIs. Sometimes internationalized resource identifiers, or IRIs, -may also be used, but these can be directly translated into a URI.

-

In practice we will identify two kinds of resources. Individual -resources map to a set of one element, for example "user Joe". -Collection of resources map to a set of 0 to N elements, -for example "all users".

-
-
-
+

A resource is an abstract concept. In a REST system, any information that can be named may be a resource. This includes documents, images, a collection of resources and any other information. Any information that can be the target of an hypertext link can be a resource.

+

A resource is a conceptual mapping to a set of entities. The set of entities evolves over time; a resource doesn't. For example, a resource can map to "users who have logged in this past month" and another to "all users". At some point in time they may map to the same set of entities, because all users logged in this past month. But they are still different resources. Similarly, if nobody logged in recently, then the first resource may map to the empty set. This resource exists regardless of the information it maps to.

+

Resources are identified by uniform resource identifiers, also known as URIs. Sometimes internationalized resource identifiers, or IRIs, may also be used, but these can be directly translated into a URI.

+

In practice we will identify two kinds of resources. Individual resources map to a set of one element, for example "user Joe". Collection of resources map to a set of 0 to N elements, for example "all users".

Resource representations

-
-

The representation of a resource is a sequence of bytes associated -with metadata.

-

The metadata comes as a list of key-value pairs, where the name -corresponds to a standard that defines the value’s structure and -semantics. With HTTP, the metadata comes in the form of request -or response headers. The headers' structure and semantics are well -defined in the HTTP standard. Metadata includes representation -metadata, resource metadata and control data.

-

The representation metadata gives information about the -representation, such as its media type, the date of last -modification, or even a checksum.

-

Resource metadata could be link to related resources or -information about additional representations of the resource.

-

Control data allows parameterizing the request or response. -For example, we may only want the representation returned if -it is more recent than the one we have in cache. Similarly, -we may want to instruct the client about how it should cache -the representation. This isn’t restricted to caching. We may, -for example, want to store a new representation of a resource -only if it wasn’t modified since we first retrieved it.

-

The data format of a representation is also known as the media -type. Some media types are intended for direct rendering to the -user, while others are intended for automated processing. The -media type is a key component of the REST architecture.

-
-
-
+

The representation of a resource is a sequence of bytes associated with metadata.

+

The metadata comes as a list of key-value pairs, where the name corresponds to a standard that defines the value's structure and semantics. With HTTP, the metadata comes in the form of request or response headers. The headers' structure and semantics are well defined in the HTTP standard. Metadata includes representation metadata, resource metadata and control data.

+

The representation metadata gives information about the representation, such as its media type, the date of last modification, or even a checksum.

+

Resource metadata could be link to related resources or information about additional representations of the resource.

+

Control data allows parameterizing the request or response. For example, we may only want the representation returned if it is more recent than the one we have in cache. Similarly, we may want to instruct the client about how it should cache the representation. This isn't restricted to caching. We may, for example, want to store a new representation of a resource only if it wasn't modified since we first retrieved it.

+

The data format of a representation is also known as the media type. Some media types are intended for direct rendering to the user, while others are intended for automated processing. The media type is a key component of the REST architecture.

Self-descriptive messages

-
-

Messages must be self-descriptive. That means that the data -format of a representation must always come with its media -type (and similarly requesting a resource involves choosing -the media type of the representation returned). If you are -sending HTML, then you must say it is HTML by sending the -media type with the representation. In HTTP this is done -using the content-type header.

-

The media type is often an IANA registered media type, like -text/html or image/png, but does not need to be. Exactly -two things are important for respecting this constraint: that -the media type is well specified, and that the sender and -recipient agree about what the media type refers to.

-

This means that you can create your own media types, like -application/x-mine, and that as long as you write the -specifications for it and that both endpoints agree about -it then the constraint is respected.

-
-
-
+

Messages must be self-descriptive. That means that the data format of a representation must always come with its media type (and similarly requesting a resource involves choosing the media type of the representation returned). If you are sending HTML, then you must say it is HTML by sending the media type with the representation. In HTTP this is done using the content-type header.

+

The media type is often an IANA registered media type, like text/html or image/png, but does not need to be. Exactly two things are important for respecting this constraint: that the media type is well specified, and that the sender and recipient agree about what the media type refers to.

+

This means that you can create your own media types, like application/x-mine, and that as long as you write the specifications for it and that both endpoints agree about it then the constraint is respected.

Hypermedia as the engine of application state

-
-

The last constraint is generally where services that claim -to be RESTful fail. Interactions with a server must be -entirely driven by hypermedia. The client does not need -any prior knowledge of the service in order to use it, -other than an entry point and of course basic understanding -of the media type of the representations, at the very least -enough to find and identify hyperlinks and link relations.

-

To give a simple example, if your service only works with -the application/json media type then this constraint -cannot be respected (as there are no concept of links in -JSON) and thus your service isn’t RESTful. This is the case -for the majority of self-proclaimed REST services.

-

On the other hand if you create a JSON based media type -that has a concept of links and link relations, then -your service might be RESTful.

-

Respecting this constraint means that the entirety of the -service becomes self-discoverable, not only the resources -in it, but also the operations you can perform on it. This -makes clients very thin as there is no need to implement -anything specific to the service to operate on it.

-
-
+

The last constraint is generally where services that claim to be RESTful fail. Interactions with a server must be entirely driven by hypermedia. The client does not need any prior knowledge of the service in order to use it, other than an entry point and of course basic understanding of the media type of the representations, at the very least enough to find and identify hyperlinks and link relations.

+

To give a simple example, if your service only works with the application/json media type then this constraint cannot be respected (as there are no concept of links in JSON) and thus your service isn't RESTful. This is the case for the majority of self-proclaimed REST services.

+

On the other hand if you create a JSON based media type that has a concept of links and link relations, then your service might be RESTful.

+

Respecting this constraint means that the entirety of the service becomes self-discoverable, not only the resources in it, but also the operations you can perform on it. This makes clients very thin as there is no need to implement anything specific to the service to operate on it.

+ diff --git a/docs/en/cowboy/2.3/guide/routing/index.html b/docs/en/cowboy/2.3/guide/routing/index.html index 5f1ef914..1a7eccc6 100644 --- a/docs/en/cowboy/2.3/guide/routing/index.html +++ b/docs/en/cowboy/2.3/guide/routing/index.html @@ -62,261 +62,181 @@

Routing

-

Cowboy does nothing by default.

-

To make Cowboy useful, you need to map URIs to Erlang modules that will -handle the requests. This is called routing.

-

When Cowboy receives a request, it tries to match the requested host and -path to the configured routes. When there’s a match, the route’s -associated handler is executed.

-

Routes need to be compiled before they can be used by Cowboy. -The result of the compilation is the dispatch rules.

-
+

Cowboy does nothing by default.

+

To make Cowboy useful, you need to map URIs to Erlang modules that will handle the requests. This is called routing.

+

When Cowboy receives a request, it tries to match the requested host and path to the configured routes. When there's a match, the route's associated handler is executed.

+

Routes need to be compiled before they can be used by Cowboy. The result of the compilation is the dispatch rules.

Syntax

-
-

The general structure for the routes is defined as follow.

-
-
-
Routes = [Host1, Host2, ... HostN].
-

Each host contains matching rules for the host along with optional -constraints, and a list of routes for the path component.

-
-
-
Host1 = {HostMatch, PathsList}.
-Host2 = {HostMatch, Constraints, PathsList}.
-

The list of routes for the path component is defined similar to the -list of hosts.

-
-
-
PathsList = [Path1, Path2, ... PathN].
-

Finally, each path contains matching rules for the path along with -optional constraints, and gives us the handler module to be used -along with its initial state.

-
-
-
Path1 = {PathMatch, Handler, InitialState}.
-Path2 = {PathMatch, Constraints, Handler, InitialState}.
-

Continue reading to learn more about the match syntax and the optional -constraints.

-
-
-
+
Path1 = {PathMatch, Handler, InitialState}.
+Path2 = {PathMatch, Constraints, Handler, InitialState}.
+
+

Continue reading to learn more about the match syntax and the optional constraints.

Match syntax

-
-

The match syntax is used to associate host names and paths with their -respective handlers.

-

The match syntax is the same for host and path with a few subtleties. -Indeed, the segments separator is different, and the host is matched -starting from the last segment going to the first. All examples will -feature both host and path match rules and explain the differences -when encountered.

-

Excluding special values that we will explain at the end of this section, -the simplest match value is a host or a path. It can be given as either -a string() or a binary().

-
-
-
PathMatch1 = "/".
-PathMatch2 = "/path/to/resource".
-
-HostMatch1 = "cowboy.example.org".
-

As you can see, all paths defined this way must start with a slash -character. Note that these two paths are identical as far as routing -is concerned.

-
-
-
PathMatch2 = "/path/to/resource".
-PathMatch3 = "/path/to/resource/".
-

Hosts with and without a trailing dot are equivalent for routing. -Similarly, hosts with and without a leading dot are also equivalent.

-
-
-
HostMatch1 = "cowboy.example.org".
-HostMatch2 = "cowboy.example.org.".
-HostMatch3 = ".cowboy.example.org".
-

It is possible to extract segments of the host and path and to store -the values in the Req object for later use. We call these kind of -values bindings.

-

The syntax for bindings is very simple. A segment that begins with -the : character means that what follows until the end of the segment -is the name of the binding in which the segment value will be stored.

-
-
-
PathMatch = "/hats/:name/prices".
-HostMatch = ":subdomain.example.org".
-

If these two end up matching when routing, you will end up with two -bindings defined, subdomain and name, each containing the -segment value where they were defined. For example, the URL -http://test.example.org/hats/wild_cowboy_legendary/prices will -result in having the value test bound to the name subdomain -and the value wild_cowboy_legendary bound to the name name. -They can later be retrieved using cowboy_req:binding/{2,3}. The -binding name must be given as an atom.

-

There is a special binding name you can use to mimic the underscore -variable in Erlang. Any match against the _ binding will succeed -but the data will be discarded. This is especially useful for -matching against many domain names in one go.

-
-
-
HostMatch = "ninenines.:_".
-

Similarly, it is possible to have optional segments. Anything -between brackets is optional.

-
-
-
PathMatch = "/hats/[page/:number]".
-HostMatch = "[www.]ninenines.eu".
-

You can also have imbricated optional segments.

-
-
-
PathMatch = "/hats/[page/[:number]]".
-

You can retrieve the rest of the host or path using [...]. -In the case of hosts it will match anything before, in the case -of paths anything after the previously matched segments. It is -a special case of optional segments, in that it can have -zero, one or many segments. You can then find the segments using -cowboy_req:host_info/1 and cowboy_req:path_info/1 respectively. -They will be represented as a list of segments.

-
-
-
PathMatch = "/hats/[...]".
-HostMatch = "[...]ninenines.eu".
-

If a binding appears twice in the routing rules, then the match -will succeed only if they share the same value. This copies the -Erlang pattern matching behavior.

-
-
-
PathMatch = "/hats/:name/:name".
-

This is also true when an optional segment is present. In this -case the two values must be identical only if the segment is -available.

-
-
-
PathMatch = "/hats/:name/[:name]".
-

If a binding is defined in both the host and path, then they must -also share the same value.

-
-
-
PathMatch = "/:user/[...]".
-HostMatch = ":user.github.com".
-

Finally, there are two special match values that can be used. The -first is the atom '_' which will match any host or path.

-
-
-
PathMatch = '_'.
-HostMatch = '_'.
-

The second is the special host match "*" which will match the -wildcard path, generally used alongside the OPTIONS method.

-
-
-
HostMatch = "*".
-
- -
+
HostMatch = "*".
+

Constraints

-
-

After the matching has completed, the resulting bindings can be tested -against a set of constraints. Constraints are only tested when the -binding is defined. They run in the order you defined them. The match -will succeed only if they all succeed. If the match fails, then Cowboy -tries the next route in the list.

-

The format used for constraints is the same as match functions in -cowboy_req: they are provided as a list of fields which may have -one or more constraints. While the router accepts the same format, -it will skip fields with no constraints and will also ignore default -values, if any.

-

Read more about constraints.

-
- -
+

After the matching has completed, the resulting bindings can be tested against a set of constraints. Constraints are only tested when the binding is defined. They run in the order you defined them. The match will succeed only if they all succeed. If the match fails, then Cowboy tries the next route in the list.

+

The format used for constraints is the same as match functions in cowboy_req: they are provided as a list of fields which may have one or more constraints. While the router accepts the same format, it will skip fields with no constraints and will also ignore default values, if any.

+

Read more about constraints.

Compilation

-
-

The routes must be compiled before Cowboy can use them. The compilation -step normalizes the routes to simplify the code and speed up the -execution, but the routes are still looked up one by one in the end. -Faster compilation strategies could be to compile the routes directly -to Erlang code, but would require heavier dependencies.

-

To compile routes, just call the appropriate function:

-
-
-
Dispatch = cowboy_router:compile([
-    %% {HostMatch, list({PathMatch, Handler, InitialState})}
-    {'_', [{'_', my_handler, #{}}]}
+
Dispatch = cowboy_router:compile([
+    %% {HostMatch, list({PathMatch, Handler, InitialState})}
+    {'_', [{'_', my_handler, #{}}]}
 ]),
-%% Name, NbAcceptors, TransOpts, ProtoOpts
-cowboy:start_clear(my_http_listener,
-    [{port, 8080}],
-    #{env => #{dispatch => Dispatch}}
-).
-
-
-
+%% Name, NbAcceptors, TransOpts, ProtoOpts +cowboy:start_clear(my_http_listener, + [{port, 8080}], + #{env => #{dispatch => Dispatch}} +). +

Live update

-
-

You can use the cowboy:set_env/3 function for updating the dispatch -list used by routing. This will apply to all new connections accepted -by the listener:

-
-
-
Dispatch = cowboy_router:compile(Routes),
-cowboy:set_env(my_http_listener, dispatch, Dispatch).
-

Note that you need to compile the routes again before updating.

-
- +
Dispatch = cowboy_router:compile(Routes),
+cowboy:set_env(my_http_listener, dispatch, Dispatch).
+ +

Note that you need to compile the routes again before updating.

+ diff --git a/docs/en/cowboy/2.3/guide/specs/index.html b/docs/en/cowboy/2.3/guide/specs/index.html index 49ba1e1a..b16bd2fa 100644 --- a/docs/en/cowboy/2.3/guide/specs/index.html +++ b/docs/en/cowboy/2.3/guide/specs/index.html @@ -62,859 +62,345 @@

HTTP and other specifications

-

This chapter intends to list all the specification documents -for or related to HTTP.

-
+

This chapter intends to list all the specification documents for or related to HTTP.

HTTP

-
-

IANA Registries

-
-
-
+

Current

-
    -
  • -

    -CORS: Cross-Origin Resource Sharing -

    -
    • -
  • -

    -CSP2: Content Security Policy Level 2 -

    -
    • -
  • -

    -DNT: Tracking Preference Expression (DNT) -

    -
    • -
  • -

    -eventsource: Server-Sent Events -

    -
    • -
  • -

    -Form content types: Form content types -

    -
    • -
  • -

    -Preload: Preload -

    -
    • -
  • -

    -PROXY: The PROXY protocol -

    -
    • -
  • -

    -REST: Fielding’s Dissertation -

    -
    • -
  • -

    -RFC 1945: HTTP/1.0 -

    -
    • -
  • -

    -RFC 1951: DEFLATE Compressed Data Format Specification version 1.3 -

    -
    • -
  • -

    -RFC 1952: GZIP file format specification version 4.3 -

    -
    • -
  • -

    -RFC 2046: Multipart media type (in MIME Part Two: Media Types) -

    -
    • -
  • -

    -RFC 2295: Transparent Content Negotiation in HTTP -

    -
    • -
  • -

    -RFC 2296: HTTP Remote Variant Selection Algorithm: RVSA/1.0 -

    -
    • -
  • -

    -RFC 2817: Upgrading to TLS Within HTTP/1.1 -

    -
    • -
  • -

    -RFC 2818: HTTP Over TLS -

    -
    • -
  • -

    -RFC 3230: Instance Digests in HTTP -

    -
    • -
  • -

    -RFC 4559: SPNEGO-based Kerberos and NTLM HTTP Authentication in Microsoft Windows -

    -
    • -
  • -

    -RFC 5789: PATCH Method for HTTP -

    -
    • -
  • -

    -RFC 5843: Additional Hash Algorithms for HTTP Instance Digests -

    -
    • -
  • -

    -RFC 5861: HTTP Cache-Control Extensions for Stale Content -

    -
    • -
  • -

    -RFC 5988: Web Linking -

    -
    • -
  • -

    -RFC 6265: HTTP State Management Mechanism -

    -
    • -
  • -

    -RFC 6266: Use of the Content-Disposition Header Field -

    -
    • -
  • -

    -RFC 6454: The Web Origin Concept -

    -
    • -
  • -

    -RFC 6455: The WebSocket Protocol -

    -
    • -
  • -

    -RFC 6585: Additional HTTP Status Codes -

    -
    • -
  • -

    -RFC 6750: The OAuth 2.0 Authorization Framework: Bearer Token Usage -

    -
    • -
  • -

    -RFC 6797: HTTP Strict Transport Security (HSTS) -

    -
    • -
  • -

    -RFC 6903: Additional Link Relation Types -

    -
    • -
  • -

    -RFC 7034: HTTP Header Field X-Frame-Options -

    -
    • -
  • -

    -RFC 7089: Time-Based Access to Resource States: Memento -

    -
    • -
  • -

    -RFC 7230: HTTP/1.1 Message Syntax and Routing -

    -
    • -
  • -

    -RFC 7231: HTTP/1.1 Semantics and Content -

    -
    • -
  • -

    -RFC 7232: HTTP/1.1 Conditional Requests -

    -
    • -
  • -

    -RFC 7233: HTTP/1.1 Range Requests -

    -
    • -
  • -

    -RFC 7234: HTTP/1.1 Caching -

    -
    • -
  • -

    -RFC 7235: HTTP/1.1 Authentication -

    -
    • -
  • -

    -RFC 7239: Forwarded HTTP Extension -

    -
    • -
  • -

    -RFC 7240: Prefer Header for HTTP -

    -
    • -
  • -

    -RFC 7469: Public Key Pinning Extension for HTTP -

    -
    • -
  • -

    -RFC 7486: HTTP Origin-Bound Authentication (HOBA) -

    -
    • -
  • -

    -RFC 7538: HTTP Status Code 308 (Permanent Redirect) -

    -
    • -
  • -

    -RFC 7540: Hypertext Transfer Protocol Version 2 (HTTP/2) -

    -
    • -
  • -

    -RFC 7541: HPACK: Header Compression for HTTP/2 -

    -
    • -
  • -

    -RFC 7578: Returning Values from Forms: multipart/form-data -

    -
    • -
  • -

    -RFC 7615: HTTP Authentication-Info and Proxy-Authentication-Info Response Header Fields -

    -
    • -
  • -

    -RFC 7616: HTTP Digest Access Authentication -

    -
    • -
  • -

    -RFC 7617: The Basic HTTP Authentication Scheme -

    -
    • -
  • -

    -RFC 7639: The ALPN HTTP Header Field -

    -
    • -
  • -

    -RFC 7692: Compression Extensions for WebSocket -

    -
    • -
  • -

    -RFC 7694: HTTP Client-Initiated Content-Encoding -

    -
    • -
  • -

    -RFC 7725: An HTTP Status Code to Report Legal Obstacles -

    -
    • -
  • -

    -RFC 7804: Salted Challenge Response HTTP Authentication Mechanism -

    -
    • -
  • -

    -RFC 7838: HTTP Alternative Services -

    -
    • -
  • -

    -RFC 7932: Brotli Compressed Data Format -

    -
    • -
  • -

    -RFC 7936: Clarifying Registry Procedures for the WebSocket Subprotocol Name Registry -

    -
    • -
  • -

    -RFC 8053: HTTP Authentication Extensions for Interactive Clients -

    -
    • -
  • -

    -RFC 8164: Opportunistic Security for HTTP/2 -

    -
    • -
  • -

    -RFC 8187: Indicating Character Encoding and Language for HTTP Header Field Parameters -

    -
    • -
  • -

    -RFC 8188: Encrypted Content-Encoding for HTTP -

    -
    • -
  • -

    -RFC 8246: HTTP Immutable Responses -

    -
    • -
  • -

    -RFC 8297: An HTTP Status Code for Indicating Hints -

    -
    • -
  • -

    -RFC 8336: The ORIGIN HTTP/2 Frame -

    -
    • -
  • -

    -Webmention: Webmention -

    -
    • -
-
-
+
  • CORS: Cross-Origin Resource Sharing +
    • +
  • CSP2: Content Security Policy Level 2 +
    • +
  • DNT: Tracking Preference Expression (DNT) +
    • +
  • eventsource: Server-Sent Events +
    • +
  • Form content types: Form content types +
    • +
  • Preload: Preload +
    • +
  • PROXY: The PROXY protocol +
    • +
  • REST: Fielding's Dissertation +
    • +
  • RFC 1945: HTTP/1.0 +
    • +
  • RFC 1951: DEFLATE Compressed Data Format Specification version 1.3 +
    • +
  • RFC 1952: GZIP file format specification version 4.3 +
    • +
  • RFC 2046: Multipart media type (in MIME Part Two: Media Types) +
    • +
  • RFC 2295: Transparent Content Negotiation in HTTP +
    • +
  • RFC 2296: HTTP Remote Variant Selection Algorithm: RVSA/1.0 +
    • +
  • RFC 2817: Upgrading to TLS Within HTTP/1.1 +
    • +
  • RFC 2818: HTTP Over TLS +
    • +
  • RFC 3230: Instance Digests in HTTP +
    • +
  • RFC 4559: SPNEGO-based Kerberos and NTLM HTTP Authentication in Microsoft Windows +
    • +
  • RFC 5789: PATCH Method for HTTP +
    • +
  • RFC 5843: Additional Hash Algorithms for HTTP Instance Digests +
    • +
  • RFC 5861: HTTP Cache-Control Extensions for Stale Content +
    • +
  • RFC 5988: Web Linking +
    • +
  • RFC 6265: HTTP State Management Mechanism +
    • +
  • RFC 6266: Use of the Content-Disposition Header Field +
    • +
  • RFC 6454: The Web Origin Concept +
    • +
  • RFC 6455: The WebSocket Protocol +
    • +
  • RFC 6585: Additional HTTP Status Codes +
    • +
  • RFC 6750: The OAuth 2.0 Authorization Framework: Bearer Token Usage +
    • +
  • RFC 6797: HTTP Strict Transport Security (HSTS) +
    • +
  • RFC 6903: Additional Link Relation Types +
    • +
  • RFC 7034: HTTP Header Field X-Frame-Options +
    • +
  • RFC 7089: Time-Based Access to Resource States: Memento +
    • +
  • RFC 7230: HTTP/1.1 Message Syntax and Routing +
    • +
  • RFC 7231: HTTP/1.1 Semantics and Content +
    • +
  • RFC 7232: HTTP/1.1 Conditional Requests +
    • +
  • RFC 7233: HTTP/1.1 Range Requests +
    • +
  • RFC 7234: HTTP/1.1 Caching +
    • +
  • RFC 7235: HTTP/1.1 Authentication +
    • +
  • RFC 7239: Forwarded HTTP Extension +
    • +
  • RFC 7240: Prefer Header for HTTP +
    • +
  • RFC 7469: Public Key Pinning Extension for HTTP +
    • +
  • RFC 7486: HTTP Origin-Bound Authentication (HOBA) +
    • +
  • RFC 7538: HTTP Status Code 308 (Permanent Redirect) +
    • +
  • RFC 7540: Hypertext Transfer Protocol Version 2 (HTTP/2) +
    • +
  • RFC 7541: HPACK: Header Compression for HTTP/2 +
    • +
  • RFC 7578: Returning Values from Forms: multipart/form-data +
    • +
  • RFC 7615: HTTP Authentication-Info and Proxy-Authentication-Info Response Header Fields +
    • +
  • RFC 7616: HTTP Digest Access Authentication +
    • +
  • RFC 7617: The Basic HTTP Authentication Scheme +
    • +
  • RFC 7639: The ALPN HTTP Header Field +
    • +
  • RFC 7692: Compression Extensions for WebSocket +
    • +
  • RFC 7694: HTTP Client-Initiated Content-Encoding +
    • +
  • RFC 7725: An HTTP Status Code to Report Legal Obstacles +
    • +
  • RFC 7804: Salted Challenge Response HTTP Authentication Mechanism +
    • +
  • RFC 7838: HTTP Alternative Services +
    • +
  • RFC 7932: Brotli Compressed Data Format +
    • +
  • RFC 7936: Clarifying Registry Procedures for the WebSocket Subprotocol Name Registry +
    • +
  • RFC 8053: HTTP Authentication Extensions for Interactive Clients +
    • +
  • RFC 8164: Opportunistic Security for HTTP/2 +
    • +
  • RFC 8187: Indicating Character Encoding and Language for HTTP Header Field Parameters +
    • +
  • RFC 8188: Encrypted Content-Encoding for HTTP +
    • +
  • RFC 8246: HTTP Immutable Responses +
    • +
  • RFC 8297: An HTTP Status Code for Indicating Hints +
    • +
  • RFC 8336: The ORIGIN HTTP/2 Frame +
    • +
  • Webmention: Webmention +
    • +

Upcoming

-
-
-
+

Informative

-
    -
  • -

    -Architecture of the World Wide Web -

    -
    • -
  • -

    -RFC 2936: HTTP MIME Type Handler Detection -

    -
    • -
  • -

    -RFC 2964: Use of HTTP State Management -

    -
    • -
  • -

    -RFC 3143: Known HTTP Proxy/Caching Problems -

    -
    • -
  • -

    -RFC 6202: Known Issues and Best Practices for the Use of Long Polling and Streaming in Bidirectional HTTP -

    -
    • -
  • -

    -RFC 6838: Media Type Specifications and Registration Procedures -

    -
    • -
  • -

    -RFC 7478: Web Real-Time Communication Use Cases and Requirements -

    -
    • -
-
-
+
  • Architecture of the World Wide Web +
    • +
  • RFC 2936: HTTP MIME Type Handler Detection +
    • +
  • RFC 2964: Use of HTTP State Management +
    • +
  • RFC 3143: Known HTTP Proxy/Caching Problems +
    • +
  • RFC 6202: Known Issues and Best Practices for the Use of Long Polling and Streaming in Bidirectional HTTP +
    • +
  • RFC 6838: Media Type Specifications and Registration Procedures +
    • +
  • RFC 7478: Web Real-Time Communication Use Cases and Requirements +
    • +

Related

-
-
-
+

Seemingly obsolete

-
    -
  • -

    -RFC 2227: Simple Hit-Metering and Usage-Limiting for HTTP -

    -
    • -
  • -

    -RFC 2310: The Safe Response Header Field -

    -
    • -
  • -

    -RFC 2324: Hyper Text Coffee Pot Control Protocol (HTCPCP/1.0) -

    -
    • -
  • -

    -RFC 2660: The Secure HyperText Transfer Protocol -

    -
    • -
  • -

    -RFC 2774: An HTTP Extension Framework -

    -
    • -
  • -

    -RFC 2965: HTTP State Management Mechanism (Cookie2) -

    -
    • -
  • -

    -RFC 3229: Delta encoding in HTTP -

    -
    • -
  • -

    -RFC 7168: The Hyper Text Coffee Pot Control Protocol for Tea Efflux Appliances (HTCPCP-TEA) -

    -
    • -
  • -

    -SPDY: SPDY Protocol -

    -
    • -
  • -

    -x-webkit-deflate-frame: Deprecated Websocket compression -

    -
    • -
-
-
-
-
+

URL

-
-
-
-
-
+

WebDAV

-
-
    -
  • -

    -RFC 3253: Versioning Extensions to WebDAV -

    -
    • -
  • -

    -RFC 3648: WebDAV Ordered Collections Protocol -

    -
    • -
  • -

    -RFC 3744: WebDAV Access Control Protocol -

    -
    • -
  • -

    -RFC 4316: Datatypes for WebDAV Properties -

    -
    • -
  • -

    -RFC 4331: Quota and Size Properties for DAV Collections -

    -
    • -
  • -

    -RFC 4437: WebDAV Redirect Reference Resources -

    -
    • -
  • -

    -RFC 4709: Mounting WebDAV Servers -

    -
    • -
  • -

    -RFC 4791: Calendaring Extensions to WebDAV (CalDAV) -

    -
    • -
  • -

    -RFC 4918: HTTP Extensions for WebDAV -

    -
    • -
  • -

    -RFC 5323: WebDAV SEARCH -

    -
    • -
  • -

    -RFC 5397: WebDAV Current Principal Extension -

    -
    • -
  • -

    -RFC 5689: Extended MKCOL for WebDAV -

    -
    • -
  • -

    -RFC 5842: Binding Extensions to WebDAV -

    -
    • -
  • -

    -RFC 5995: Using POST to Add Members to WebDAV Collections -

    -
    • -
  • -

    -RFC 6352: CardDAV: vCard Extensions to WebDAV -

    -
    • -
  • -

    -RFC 6578: Collection Synchronization for WebDAV -

    -
    • -
  • -

    -RFC 6638: Scheduling Extensions to CalDAV -

    -
    • -
  • -

    -RFC 6764: Locating Services for Calendaring Extensions to WebDAV (CalDAV) and vCard Extensions to WebDAV (CardDAV) -

    -
    • -
  • -

    -RFC 7809: Calendaring Extensions to WebDAV (CalDAV): Time Zones by Reference -

    -
    • -
  • -

    -RFC 7953: Calendar Availability -

    -
    • -
  • -

    -RFC 8144: Use of the Prefer Header Field in WebDAV -

    -
    • -
-
-
-
+

CoAP

-
-
    -
  • -

    -RFC 7252: The Constrained Application Protocol (CoAP) -

    -
    • -
  • -

    -RFC 7390: Group Communication for CoAP -

    -
    • -
  • -

    -RFC 7641: Observing Resources in CoAP -

    -
    • -
  • -

    -RFC 7650: A CoAP Usage for REsource LOcation And Discovery (RELOAD) -

    -
    • -
  • -

    -RFC 7959: Block-Wise Transfers in CoAP -

    -
    • -
  • -

    -RFC 7967: CoAP Option for No Server Response -

    -
    • -
  • -

    -RFC 8075: Guidelines for Mapping Implementations: HTTP to CoAP -

    -
    • -
  • -

    -RFC 8132: PATCH and FETCH Methods for CoAP -

    -
    • -
  • -

    -RFC 8323: CoAP over TCP, TLS, and WebSockets -

    -
    • -
-
-
+ + diff --git a/docs/en/cowboy/2.3/guide/static_files/index.html b/docs/en/cowboy/2.3/guide/static_files/index.html index 5b5bbd0b..f3fe3254 100644 --- a/docs/en/cowboy/2.3/guide/static_files/index.html +++ b/docs/en/cowboy/2.3/guide/static_files/index.html @@ -62,173 +62,101 @@

Static files

-

Cowboy comes with a ready to use handler for serving static -files. It is provided as a convenience for serving files -during development.

-

For systems in production, consider using one of the many -Content Distribution Network (CDN) available on the market, -as they are the best solution for serving files.

-

The static handler can serve either one file or all files -from a given directory. The etag generation and mime types -can be configured.

-
+

Cowboy comes with a ready to use handler for serving static files. It is provided as a convenience for serving files during development.

+

For systems in production, consider using one of the many Content Distribution Network (CDN) available on the market, as they are the best solution for serving files.

+

The static handler can serve either one file or all files from a given directory. The etag generation and mime types can be configured.

Serve one file

-
-

You can use the static handler to serve one specific file -from an application’s private directory. This is particularly -useful to serve an index.html file when the client requests -the / path, for example. The path configured is relative -to the given application’s private directory.

-

The following rule will serve the file static/index.html -from the application my_app's priv directory whenever the -path / is accessed:

-
-
-
{"/", cowboy_static, {priv_file, my_app, "static/index.html"}}
-

You can also specify the absolute path to a file, or the -path to the file relative to the current directory:

-
-
-
{"/", cowboy_static, {file, "/var/www/index.html"}}
-
-
-
+
{"/", cowboy_static, {file, "/var/www/index.html"}}
+

Serve all files from a directory

-
-

You can also use the static handler to serve all files that -can be found in the configured directory. The handler will -use the path_info information to resolve the file location, -which means that your route must end with a [...] pattern -for it to work. All files are served, including the ones that -may be found in subfolders.

-

You can specify the directory relative to an application’s -private directory.

-

The following rule will serve any file found in the application -my_app's priv directory inside the static/assets folder -whenever the requested path begins with /assets/:

-
-
-
{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets"}}
-

You can also specify the absolute path to the directory or -set it relative to the current directory:

-
-
-
{"/assets/[...]", cowboy_static, {dir, "/var/www/assets"}}
-
- -
+
{"/assets/[...]", cowboy_static, {dir, "/var/www/assets"}}
+

Customize the mimetype detection

-
-

By default, Cowboy will attempt to recognize the mimetype -of your static files by looking at the extension.

-

You can override the function that figures out the mimetype -of the static files. It can be useful when Cowboy is missing -a mimetype you need to handle, or when you want to reduce -the list to make lookups faster. You can also give a -hard-coded mimetype that will be used unconditionally.

-

Cowboy comes with two functions built-in. The default -function only handles common file types used when building -Web applications. The other function is an extensive list -of hundreds of mimetypes that should cover almost any need -you may have. You can of course create your own function.

-

To use the default function, you should not have to configure -anything, as it is the default. If you insist, though, the -following will do the job:

-
-
-
{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets",
-    [{mimetypes, cow_mimetypes, web}]}}
-

As you can see, there is an optional field that may contain -a list of less used options, like mimetypes or etag. All option -types have this optional field.

-

To use the function that will detect almost any mimetype, -the following configuration will do:

-
-
-
{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets",
-    [{mimetypes, cow_mimetypes, all}]}}
-

You probably noticed the pattern by now. The configuration -expects a module and a function name, so you can use any -of your own functions instead:

-
-
-
{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets",
-    [{mimetypes, Module, Function}]}}
-

The function that performs the mimetype detection receives -a single argument that is the path to the file on disk. It -is recommended to return the mimetype in tuple form, although -a binary string is also allowed (but will require extra -processing). If the function can’t figure out the mimetype, -then it should return {<<"application">>, <<"octet-stream">>, []}.

-

When the static handler fails to find the extension, -it will send the file as application/octet-stream. -A browser receiving such file will attempt to download it -directly to disk.

-

Finally, the mimetype can be hard-coded for all files. -This is especially useful in combination with the file -and priv_file options as it avoids needless computation:

-
-
-
{"/", cowboy_static, {priv_file, my_app, "static/index.html",
-    [{mimetypes, {<<"text">>, <<"html">>, []}}]}}
-
- -
+
{"/", cowboy_static, {priv_file, my_app, "static/index.html",
+    [{mimetypes, {<<"text">>, <<"html">>, []}}]}}
+

Generate an etag

-
-

By default, the static handler will generate an etag header -value based on the size and modified time. This solution -can not be applied to all systems though. It would perform -rather poorly over a cluster of nodes, for example, as the -file metadata will vary from server to server, giving a -different etag on each server.

-

You can however change the way the etag is calculated:

-
-
-
{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets",
-    [{etag, Module, Function}]}}
-

This function will receive three arguments: the path to the -file on disk, the size of the file and the last modification -time. In a distributed setup, you would typically use the -file path to retrieve an etag value that is identical across -all your servers.

-

You can also completely disable etag handling:

-
-
-
{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets",
-    [{etag, false}]}}
-
- +
{"/assets/[...]", cowboy_static, {priv_dir, my_app, "static/assets",
+    [{etag, false}]}}
+ + diff --git a/docs/en/cowboy/2.3/guide/streams/index.html b/docs/en/cowboy/2.3/guide/streams/index.html index 4c621525..7f936431 100644 --- a/docs/en/cowboy/2.3/guide/streams/index.html +++ b/docs/en/cowboy/2.3/guide/streams/index.html @@ -62,61 +62,23 @@

Streams

-

A stream is the set of messages that form an HTTP -request/response pair.

-

The term stream comes from HTTP/2. In Cowboy, it is -also used when talking about HTTP/1.1 or HTTP/1.0. -It should not be confused with streaming the request -or response body.

-

All versions of HTTP allow clients to initiate -streams. HTTP/2 is the only one also allowing servers, -through its server push feature. Both client and -server-initiated streams go through the same process -in Cowboy.

-
+

A stream is the set of messages that form an HTTP request/response pair.

+

The term stream comes from HTTP/2. In Cowboy, it is also used when talking about HTTP/1.1 or HTTP/1.0. It should not be confused with streaming the request or response body.

+

All versions of HTTP allow clients to initiate streams. HTTP/2 is the only one also allowing servers, through its server push feature. Both client and server-initiated streams go through the same process in Cowboy.

Stream handlers

-
-

Stream handlers must implement five different callbacks. -Four of them are directly related; one is special.

-

All callbacks receives the stream ID as first argument.

-

Most of them can return a list of commands to be executed -by Cowboy. When callbacks are chained, it is possible to -intercept and modify these commands. This can be useful -for modifying responses for example.

-

The init/3 callback is invoked when a new request -comes in. It receives the Req object and the protocol options -for this listener.

-

The data/4 callback is invoked when data from the request -body is received. It receives both this data and a flag -indicating whether more is to be expected.

-

The info/3 callback is invoked when an Erlang message is -received for this stream. They will typically be messages -sent by the request process.

-

Finally the terminate/3 callback is invoked with the -terminate reason for the stream. The return value is ignored. -Note that as with all terminate callbacks in Erlang, there -is no strong guarantee that it will be called.

-

The special callback early_error/5 is called when an error -occurs before the request headers were fully received and -Cowboy is sending a response. It receives the partial Req -object, the error reason, the protocol options and the response -Cowboy will send. This response must be returned, possibly -modified.

-
-
-
+

Stream handlers must implement five different callbacks. Four of them are directly related; one is special.

+

All callbacks receives the stream ID as first argument.

+

Most of them can return a list of commands to be executed by Cowboy. When callbacks are chained, it is possible to intercept and modify these commands. This can be useful for modifying responses for example.

+

The init/3 callback is invoked when a new request comes in. It receives the Req object and the protocol options for this listener.

+

The data/4 callback is invoked when data from the request body is received. It receives both this data and a flag indicating whether more is to be expected.

+

The info/3 callback is invoked when an Erlang message is received for this stream. They will typically be messages sent by the request process.

+

Finally the terminate/3 callback is invoked with the terminate reason for the stream. The return value is ignored. Note that as with all terminate callbacks in Erlang, there is no strong guarantee that it will be called.

+

The special callback early_error/5 is called when an error occurs before the request headers were fully received and Cowboy is sending a response. It receives the partial Req object, the error reason, the protocol options and the response Cowboy will send. This response must be returned, possibly modified.

Built-in handlers

-
-

Cowboy comes with two handlers.

-

cowboy_stream_h is the default stream handler. -It is the core of much of the functionality of Cowboy. -All chains of stream handlers should call it last.

-

cowboy_compress_h will automatically compress -responses when possible. It is not enabled by default. -It is a good example for writing your own handlers -that will modify responses.

-
-
+

Cowboy comes with two handlers.

+

cowboy_stream_h is the default stream handler. It is the core of much of the functionality of Cowboy. All chains of stream handlers should call it last.

+

cowboy_compress_h will automatically compress responses when possible. It is not enabled by default. It is a good example for writing your own handlers that will modify responses.

+ diff --git a/docs/en/cowboy/2.3/guide/ws_handlers/index.html b/docs/en/cowboy/2.3/guide/ws_handlers/index.html index ab028875..6fca9cf9 100644 --- a/docs/en/cowboy/2.3/guide/ws_handlers/index.html +++ b/docs/en/cowboy/2.3/guide/ws_handlers/index.html @@ -62,297 +62,190 @@

Websocket handlers

-

Websocket handlers provide an interface for upgrading HTTP/1.1 -connections to Websocket and sending or receiving frames on -the Websocket connection.

-

As Websocket connections are established through the HTTP/1.1 -upgrade mechanism, Websocket handlers need to be able to first -receive the HTTP request for the upgrade, before switching to -Websocket and taking over the connection. They can then receive -or send Websocket frames, handle incoming Erlang messages or -close the connection.

-
+

Websocket handlers provide an interface for upgrading HTTP/1.1 connections to Websocket and sending or receiving frames on the Websocket connection.

+

As Websocket connections are established through the HTTP/1.1 upgrade mechanism, Websocket handlers need to be able to first receive the HTTP request for the upgrade, before switching to Websocket and taking over the connection. They can then receive or send Websocket frames, handle incoming Erlang messages or close the connection.

Upgrade

-
-

The init/2 callback is called when the request is received. -To establish a Websocket connection, you must switch to the -cowboy_websocket module:

-
-
-
init(Req, State) ->
-    {cowboy_websocket, Req, State}.
-

Cowboy will perform the Websocket handshake immediately. Note -that the handshake will fail if the client did not request an -upgrade to Websocket.

-

The Req object becomes unavailable after this function returns. -Any information required for proper execution of the Websocket -handler must be saved in the state.

-
-
-
-

Subprotocol

-
-

The client may provide a list of Websocket subprotocols it -supports in the sec-websocket-protocol header. The server must -select one of them and send it back to the client or the -handshake will fail.

-

For example, a client could understand both STOMP and MQTT over -Websocket, and provide the header:

-
-
-
sec-websocket-protocol: v12.stomp, mqtt
+
init(Req, State) ->
+    {cowboy_websocket, Req, State}.
-

If the server only understands MQTT it can return:

-
-
-
sec-websocket-protocol: mqtt
-
-

This selection must be done in init/2. An example usage could -be:

-
-
-
init(Req0, State) ->
-    case cowboy_req:parse_header(<<"sec-websocket-protocol">>, Req0) of
-        undefined ->
-            {cowboy_websocket, Req0, State};
-        Subprotocols ->
-            case lists:keymember(<<"mqtt">>, 1, Subprotocols) of
-                true ->
-                    Req = cowboy_req:set_resp_header(<<"sec-websocket-protocol">>,
-                        <<"mqtt">>, Req0),
-                    {cowboy_websocket, Req, State};
-                false ->
-                    Req = cowboy_req:reply(400, Req0),
-                    {ok, Req, State}
-            end
-    end.
-
-
-
+
init(Req0, State) ->
+    case cowboy_req:parse_header(<<"sec-websocket-protocol">>, Req0) of
+        undefined ->
+            {cowboy_websocket, Req0, State};
+        Subprotocols ->
+            case lists:keymember(<<"mqtt">>, 1, Subprotocols) of
+                true ->
+                    Req = cowboy_req:set_resp_header(<<"sec-websocket-protocol">>,
+                        <<"mqtt">>, Req0),
+                    {cowboy_websocket, Req, State};
+                false ->
+                    Req = cowboy_req:reply(400, Req0),
+                    {ok, Req, State}
+            end
+    end.
+

Post-upgrade initialization

-
-

Cowboy has separate processes for handling the connection -and requests. Because Websocket takes over the connection, -the Websocket protocol handling occurs in a different -process than the request handling.

-

This is reflected in the different callbacks Websocket -handlers have. The init/2 callback is called from the -temporary request process and the websocket_ callbacks -from the connection process.

-

This means that some initialization cannot be done from -init/2. Anything that would require the current pid, -or be tied to the current pid, will not work as intended. -The optional websocket_init/1 can be used instead:

-
-
-
websocket_init(State) ->
-    erlang:start_timer(1000, self(), <<"Hello!">>),
-    {ok, State}.
-

All Websocket callbacks share the same return values. This -means that we can send frames to the client right after -the upgrade:

-
-
-
websocket_init(State) ->
-    {reply, {text, <<"Hello!">>}, State}.
-
- -
+
websocket_init(State) ->
+    {reply, {text, <<"Hello!">>}, State}.
+

Receiving frames

-
-

Cowboy will call websocket_handle/2 whenever a text, binary, -ping or pong frame arrives from the client.

-

The handler can handle or ignore the frames. It can also -send frames back to the client or stop the connection.

-

The following snippet echoes back any text frame received and -ignores all others:

-
-
-
websocket_handle(Frame = {text, _}, State) ->
-    {reply, Frame, State};
-websocket_handle(_Frame, State) ->
-    {ok, State}.
-

Note that ping and pong frames require no action from the -handler as Cowboy will automatically reply to ping frames. -They are provided for informative purposes only.

-
- -
+
websocket_handle(Frame = {text, _}, State) ->
+    {reply, Frame, State};
+websocket_handle(_Frame, State) ->
+    {ok, State}.
+
+

Note that ping and pong frames require no action from the handler as Cowboy will automatically reply to ping frames. They are provided for informative purposes only.

Receiving Erlang messages

-
-

Cowboy will call websocket_info/2 whenever an Erlang message -arrives.

-

The handler can handle or ignore the messages. It can also -send frames to the client or stop the connection.

-

The following snippet forwards log messages to the client -and ignores all others:

-
-
-
websocket_info({log, Text}, State) ->
-    {reply, {text, Text}, State};
-websocket_info(_Info, State) ->
-    {ok, State}.
-
- -
+
websocket_info({log, Text}, State) ->
+    {reply, {text, Text}, State};
+websocket_info(_Info, State) ->
+    {ok, State}.
+

Sending frames

-
-

All websocket_ callbacks share return values. They may -send zero, one or many frames to the client.

-

To send nothing, just return an ok tuple:

-
-
+ + +

All websocket_ callbacks share return values. They may send zero, one or many frames to the client.

+

To send nothing, just return an ok tuple:

+
-
websocket_info(_Info, State) ->
-    {ok, State}.
-

To send one frame, return a reply tuple with the frame to send:

-
-
-
websocket_info(_Info, State) ->
-    {reply, {text, <<"Hello!">>}, State}.
-

You can send frames of any type: text, binary, ping, pong -or close frames.

-

To send many frames at once, return a reply tuple with the -list of frames to send:

-
-
-
websocket_info(_Info, State) ->
-    {reply, [
-        {text, "Hello"},
-        {text, <<"world!">>},
-        {binary, <<0:8000>>}
-    ], State}.
-

They are sent in the given order.

-
-
-
+
websocket_info(_Info, State) ->
+    {reply, [
+        {text, "Hello"},
+        {text, <<"world!">>},
+        {binary, <<0:8000>>}
+    ], State}.
+
+

They are sent in the given order.

Keeping the connection alive

-
-

Cowboy will automatically respond to ping frames sent by -the client. They are still forwarded to the handler for -informative purposes, but no further action is required.

-

Cowboy does not send ping frames itself. The handler can -do it if required. A better solution in most cases is to -let the client handle pings. Doing it from the handler -would imply having an additional timer per connection and -this can be a considerable cost for servers that need to -handle large numbers of connections.

-

Cowboy can be configured to close idle connections -automatically. It is highly recommended to configure -a timeout here, to avoid having processes linger longer -than needed.

-

The init/2 callback can set the timeout to be used -for the connection. For example, this would make Cowboy -close connections idle for more than 30 seconds:

-
-
-
init(Req, State) ->
-    {cowboy_websocket, Req, State, #{
-        idle_timeout => 30000}}.
-

This value cannot be changed once it is set. It defaults to -60000.

-
- -
+
init(Req, State) ->
+    {cowboy_websocket, Req, State, #{
+        idle_timeout => 30000}}.
+
+

This value cannot be changed once it is set. It defaults to 60000.

Limiting frame sizes

-
-

Cowboy accepts frames of any size by default. You should -limit the size depending on what your handler may handle. -You can do this via the init/2 callback:

-
-
-
init(Req, State) ->
-    {cowboy_websocket, Req, State, #{
-        max_frame_size => 8000000}}.
-

The lack of limit is historical. A future version of -Cowboy will have a more reasonable default.

-
- -
+
init(Req, State) ->
+    {cowboy_websocket, Req, State, #{
+        max_frame_size => 8000000}}.
+
+

The lack of limit is historical. A future version of Cowboy will have a more reasonable default.

Saving memory

-
-

The Websocket connection process can be set to hibernate -after the callback returns.

-

Simply add an hibernate field to the ok or reply tuples:

-
-
-
websocket_init(State) ->
-    {ok, State, hibernate}.
-
-websocket_handle(_Frame, State) ->
-    {ok, State, hibernate}.
-
-websocket_info(_Info, State) ->
-    {reply, {text, <<"Hello!">>}, State, hibernate}.
-

It is highly recommended to write your handlers with -hibernate enabled, as this allows to greatly reduce the -memory usage. Do note however that an increase in the -CPU usage or latency can be observed instead, in particular -for the more busy connections.

-
- -
+
websocket_init(State) ->
+    {ok, State, hibernate}.
+
+websocket_handle(_Frame, State) ->
+    {ok, State, hibernate}.
+
+websocket_info(_Info, State) ->
+    {reply, {text, <<"Hello!">>}, State, hibernate}.
+
+

It is highly recommended to write your handlers with hibernate enabled, as this allows to greatly reduce the memory usage. Do note however that an increase in the CPU usage or latency can be observed instead, in particular for the more busy connections.

Closing the connection

-
-

The connection can be closed at any time, either by telling -Cowboy to stop it or by sending a close frame.

-

To tell Cowboy to close the connection, use a stop tuple:

-
-
-
websocket_info(_Info, State) ->
-    {stop, State}.
-

Sending a close frame will immediately initiate the closing -of the Websocket connection. Note that when sending a list of -frames that include a close frame, any frame found after the -close frame will not be sent.

-

The following example sends a close frame with a reason message:

-
-
-
websocket_info(_Info, State) ->
-    {reply, {close, 1000, <<"some-reason">>}, State}.
-
- +
websocket_info(_Info, State) ->
+    {reply, {close, 1000, <<"some-reason">>}, State}.
+ + diff --git a/docs/en/cowboy/2.3/guide/ws_protocol/index.html b/docs/en/cowboy/2.3/guide/ws_protocol/index.html index b6748a82..6f6c593a 100644 --- a/docs/en/cowboy/2.3/guide/ws_protocol/index.html +++ b/docs/en/cowboy/2.3/guide/ws_protocol/index.html @@ -62,70 +62,22 @@

The Websocket protocol

-

This chapter explains what Websocket is and why it is -a vital component of soft realtime Web applications.

-
+

This chapter explains what Websocket is and why it is a vital component of soft realtime Web applications.

Description

-
-

Websocket is an extension to HTTP that emulates plain TCP -connections between the client, typically a Web browser, -and the server. It uses the HTTP Upgrade mechanism to -establish the connection.

-

Websocket connections are fully asynchronous, unlike -HTTP/1.1 (synchronous) and HTTP/2 (asynchronous, but the -server can only initiate streams in response to requests). -With Websocket, the client and the server can both send -frames at any time without any restriction. It is closer -to TCP than any of the HTTP protocols.

-

Websocket is an IETF standard. Cowboy supports the standard -and all drafts that were previously implemented by browsers, -excluding the initial flawed draft sometimes known as -"version 0".

-
-
-
+

Websocket is an extension to HTTP that emulates plain TCP connections between the client, typically a Web browser, and the server. It uses the HTTP Upgrade mechanism to establish the connection.

+

Websocket connections are fully asynchronous, unlike HTTP/1.1 (synchronous) and HTTP/2 (asynchronous, but the server can only initiate streams in response to requests). With Websocket, the client and the server can both send frames at any time without any restriction. It is closer to TCP than any of the HTTP protocols.

+

Websocket is an IETF standard. Cowboy supports the standard and all drafts that were previously implemented by browsers, excluding the initial flawed draft sometimes known as "version 0".

Websocket vs HTTP/2

-
-

For a few years Websocket was the only way to have a -bidirectional asynchronous connection with the server. -This changed when HTTP/2 was introduced. While HTTP/2 -requires the client to first perform a request before -the server can push data, this is only a minor restriction -as the client can do so just as it connects.

-

Websocket was designed as a kind-of-TCP channel to a -server. It only defines the framing and connection -management and lets the developer implement a protocol -on top of it. For example you could implement IRC over -Websocket and use a Javascript IRC client to speak to -the server.

-

HTTP/2 on the other hand is just an improvement over -the HTTP/1.1 connection and request/response mechanism. -It has the same semantics as HTTP/1.1.

-

If all you need is to access an HTTP API, then HTTP/2 -should be your first choice. On the other hand, if what -you need is a different protocol, then you can use -Websocket to implement it.

-
-
-
+

For a few years Websocket was the only way to have a bidirectional asynchronous connection with the server. This changed when HTTP/2 was introduced. While HTTP/2 requires the client to first perform a request before the server can push data, this is only a minor restriction as the client can do so just as it connects.

+

Websocket was designed as a kind-of-TCP channel to a server. It only defines the framing and connection management and lets the developer implement a protocol on top of it. For example you could implement IRC over Websocket and use a Javascript IRC client to speak to the server.

+

HTTP/2 on the other hand is just an improvement over the HTTP/1.1 connection and request/response mechanism. It has the same semantics as HTTP/1.1.

+

If all you need is to access an HTTP API, then HTTP/2 should be your first choice. On the other hand, if what you need is a different protocol, then you can use Websocket to implement it.

Implementation

-
-

Cowboy implements Websocket as a protocol upgrade. Once the -upgrade is performed from the init/2 callback, Cowboy -switches to Websocket. Please consult the next chapter for -more information on initiating and handling Websocket -connections.

-

The implementation of Websocket in Cowboy is validated using -the Autobahn test suite, which is an extensive suite of tests -covering all aspects of the protocol. Cowboy passes the -suite with 100% success, including all optional tests.

-

Cowboy’s Websocket implementation also includes the -permessage-deflate and x-webkit-deflate-frame compression -extensions.

-

Cowboy will automatically use compression when the -compress option is returned from the init/2 function.

-
-
+

Cowboy implements Websocket as a protocol upgrade. Once the upgrade is performed from the init/2 callback, Cowboy switches to Websocket. Please consult the next chapter for more information on initiating and handling Websocket connections.

+

The implementation of Websocket in Cowboy is validated using the Autobahn test suite, which is an extensive suite of tests covering all aspects of the protocol. Cowboy passes the suite with 100% success, including all optional tests.

+

Cowboy's Websocket implementation also includes the permessage-deflate and x-webkit-deflate-frame compression extensions.

+

Cowboy will automatically use compression when the compress option is returned from the init/2 function.

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy.set_env/index.html b/docs/en/cowboy/2.3/manual/cowboy.set_env/index.html index 1b3a9279..89788f69 100644 --- a/docs/en/cowboy/2.3/manual/cowboy.set_env/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy.set_env/index.html @@ -62,117 +62,59 @@

cowboy:set_env(3)

-

Name

-
-

cowboy:set_env - Update a listener’s environment value

-
-
-
+

cowboy:set_env - Update a listener's environment value

Description

-
-
-
-
set_env(Name  :: ranch:ref(),
-        Key   :: atom(),
-        Value :: any())
-    -> ok
-

Set or update an environment value for a previously started -listener.

-

This is most useful for updating the routes dynamically, -without having to restart the listener.

-

The new value will only be available to new connections. -Pre-existing connections will still use the old value.

-
-
-
+
set_env(Name  :: ranch:ref(),
+        Key   :: atom(),
+        Value :: any())
+    -> ok
+
+

Set or update an environment value for a previously started listener.

+

This is most useful for updating the routes dynamically, without having to restart the listener.

+

The new value will only be available to new connections. Pre-existing connections will still use the old value.

Arguments

-
-
-
-Name -
-
-

-The name of the listener to update. -

-

The name of the listener is the first argument given to the -cowboy:start_clear(3), -cowboy:start_tls(3) or -ranch:start_listener(3) function.

+
Name
+

The name of the listener to update.

+

The name of the listener is the first argument given to the cowboy:start_clear(3), cowboy:start_tls(3) or ranch:start_listener(3) function.

-
-Key -
-
-

-The key in the environment map. Common keys include dispatch -and middlewares. -

+
Key
+

The key in the environment map. Common keys include dispatch and middlewares.

-
-Value -
-
-

-The new value. -

-

The type of the value differs depending on the key.

+
Value
+

The new value.

+

The type of the value differs depending on the key.

-
-
- -
+

Return value

-
-

The atom ok is returned on success.

-

An exit:badarg exception is thrown when the listener does -not exist.

-
-
-
+

The atom ok is returned on success.

+

An exit:badarg exception is thrown when the listener does not exist.

Changelog

-
-
    -
  • -

    -1.0: Function introduced. -

    +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Update a listener’s routes
-
-
Dispatch = cowboy_router:compile([
-    {'_', [
-        {"/", toppage_h, []},
-        {"/ws", websocket_h, []}
+
Dispatch = cowboy_router:compile([
+    {'_', [
+        {"/", toppage_h, []},
+        {"/ws", websocket_h, []}
     ]}
 ]),
 
-cowboy:set_env(example, dispatch, Dispatch).
-
-
-
+cowboy:set_env(example, dispatch, Dispatch). +

See also

-
-

cowboy(3), -cowboy:start_clear(3), -cowboy:start_tls(3), -ranch:set_protocol_options(3)

-
- +

cowboy(3), cowboy:start_clear(3), cowboy:start_tls(3), ranch:set_protocol_options(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy.start_clear/index.html b/docs/en/cowboy/2.3/manual/cowboy.start_clear/index.html index 9096c18c..58145cfc 100644 --- a/docs/en/cowboy/2.3/manual/cowboy.start_clear/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy.start_clear/index.html @@ -62,148 +62,77 @@

cowboy:start_clear(3)

-

Name

-
-

cowboy:start_clear - Listen for connections using plain TCP

-
-
-
+

cowboy:start_clear - Listen for connections using plain TCP

Description

-
-
-
-
start_clear(Name          :: ranch:ref(),
-            TransportOpts :: ranch_tcp:opts(),
-            ProtocolOpts  :: opts())
-    -> {ok, ListenerPid :: pid()}
-     | {error, any()}
-

Start listening for connections over a clear TCP channel.

-

Both HTTP/1.1 and HTTP/2 are supported on this listener. -HTTP/2 has two methods of establishing a connection over -a clear TCP channel. Both the upgrade and the prior knowledge -methods are supported.

-
-
-
+
start_clear(Name          :: ranch:ref(),
+            TransportOpts :: ranch_tcp:opts(),
+            ProtocolOpts  :: opts())
+    -> {ok, ListenerPid :: pid()}
+     | {error, any()}
+
+

Start listening for connections over a clear TCP channel.

+

Both HTTP/1.1 and HTTP/2 are supported on this listener. HTTP/2 has two methods of establishing a connection over a clear TCP channel. Both the upgrade and the prior knowledge methods are supported.

Arguments

-
-
-
-Name -
-
-

-The listener name is used to refer to this listener in -future calls, for example when stopping it or when -updating the routes defined. -

-

It can be any Erlang term. An atom is generally good enough, -for example api, my_app_clear or my_app_tls.

+
Name
+

The listener name is used to refer to this listener in future calls, for example when stopping it or when updating the routes defined.

+

It can be any Erlang term. An atom is generally good enough, for example api, my_app_clear or my_app_tls.

-
-TransportOpts -
-
-

-The transport options are where the TCP options, including -the listener’s port number, are defined. Transport options -are provided as a list of keys and values, for example -[{port, 8080}]. -

-

The available options are documented in the -ranch_tcp(3) manual.

+
TransportOpts
+

The transport options are where the TCP options, including the listener's port number, are defined. Transport options are provided as a list of keys and values, for example [{port, 8080}].

+

The available options are documented in the ranch_tcp(3) manual.

-
-ProtocolOpts -
-
-

-The protocol options are in a map containing all the options for -the different protocols that may be involved when connecting -to the listener, including HTTP/1.1 and HTTP/2. -

-

The HTTP/1.1 options are documented in the -cowboy_http(3) manual; -and the HTTP/2 options in -cowboy_http2(3).

+
ProtocolOpts
+

The protocol options are in a map containing all the options for the different protocols that may be involved when connecting to the listener, including HTTP/1.1 and HTTP/2.

+

The HTTP/1.1 options are documented in the cowboy_http(3) manual; and the HTTP/2 options in cowboy_http2(3).

-
-
- -
+

Return value

-
-

An ok tuple is returned on success. It contains the pid of -the top-level supervisor for the listener.

-

An error tuple is returned on error. The error reason may -be any Erlang term.

-

A common error is eaddrinuse. It indicates that the port -configured for Cowboy is already in use.

-
-
-
+

An ok tuple is returned on success. It contains the pid of the top-level supervisor for the listener.

+

An error tuple is returned on error. The error reason may be any Erlang term.

+

A common error is eaddrinuse. It indicates that the port configured for Cowboy is already in use.

Changelog

-
-
    -
  • -

    -2.0: HTTP/2 support added. -

    +
    • 2.0: HTTP/2 support added.
      • -
    • -

      -2.0: Function introduced. Replaces cowboy:start_http/4. -

      +
    • 2.0: Function introduced. Replaces cowboy:start_http/4.
      • -
-
-
-
+

Examples

-
-
-
Start a listener
-
-
Dispatch = cowboy_router:compile([
-    {'_', [
-        {"/", toppage_h, []}
+
Dispatch = cowboy_router:compile([
+    {'_', [
+        {"/", toppage_h, []}
     ]}
 ]),
 
-{ok, _} = cowboy:start_clear(example, [{port, 8080}], #{
-    env => #{dispatch => Dispatch}
-}).
-
-
Start a listener on a random port
-
-
Name = example,
+
Name = example,
 
-{ok, _} = cowboy:start_clear(Name, [], #{
-    env => #{dispatch => Dispatch}
+{ok, _} = cowboy:start_clear(Name, [], #{
+    env => #{dispatch => Dispatch}
 }),
 
-Port = ranch:get_port(Name).
-
-
-
+Port = ranch:get_port(Name). +

See also

-
-

cowboy(3), -cowboy:start_tls(3), -cowboy:stop_listener(3), -ranch(3)

-
- +

cowboy(3), cowboy:start_tls(3), cowboy:stop_listener(3), ranch(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy.start_tls/index.html b/docs/en/cowboy/2.3/manual/cowboy.start_tls/index.html index 08f92c46..41f1c02f 100644 --- a/docs/en/cowboy/2.3/manual/cowboy.start_tls/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy.start_tls/index.html @@ -62,153 +62,82 @@

cowboy:start_tls(3)

-

Name

-
-

cowboy:start_tls - Listen for connections using TLS

-
-
-
+

cowboy:start_tls - Listen for connections using TLS

Description

-
-
-
-
start_tls(Name          :: ranch:ref(),
-          TransportOpts :: ranch_ssl:opts(),
-          ProtocolOpts  :: opts())
-    -> {ok, ListenerPid :: pid()}
-     | {error, any()}
-

Start listening for connections over a secure TLS channel.

-

Both HTTP/1.1 and HTTP/2 are supported on this listener. -The ALPN TLS extension must be used to initiate an HTTP/2 -connection.

-
-
-
+
start_tls(Name          :: ranch:ref(),
+          TransportOpts :: ranch_ssl:opts(),
+          ProtocolOpts  :: opts())
+    -> {ok, ListenerPid :: pid()}
+     | {error, any()}
+
+

Start listening for connections over a secure TLS channel.

+

Both HTTP/1.1 and HTTP/2 are supported on this listener. The ALPN TLS extension must be used to initiate an HTTP/2 connection.

Arguments

-
-
-
-Name -
-
-

-The listener name is used to refer to this listener in -future calls, for example when stopping it or when -updating the routes defined. -

-

It can be any Erlang term. An atom is generally good enough, -for example api, my_app_clear or my_app_tls.

+
Name
+

The listener name is used to refer to this listener in future calls, for example when stopping it or when updating the routes defined.

+

It can be any Erlang term. An atom is generally good enough, for example api, my_app_clear or my_app_tls.

-
-TransportOpts -
-
-

-The transport options are where the TCP options, including -the listener’s port number, are defined. They also contain -the TLS options, like the server’s certificate. Transport options -are provided as a list of keys and values, for example -[{port, 8443}, {certfile, "path/to/cert.pem"}]. -

-

The available options are documented in the -ranch_ssl(3) manual.

+
TransportOpts
+

The transport options are where the TCP options, including the listener's port number, are defined. They also contain the TLS options, like the server's certificate. Transport options are provided as a list of keys and values, for example [{port, 8443}, {certfile, "path/to/cert.pem"}].

+

The available options are documented in the ranch_ssl(3) manual.

-
-ProtocolOpts -
-
-

-The protocol options are in a map containing all the options for -the different protocols that may be involved when connecting -to the listener, including HTTP/1.1 and HTTP/2. -

-

The HTTP/1.1 options are documented in the -cowboy_http(3) manual; -and the HTTP/2 options in -cowboy_http2(3).

+
ProtocolOpts
+

The protocol options are in a map containing all the options for the different protocols that may be involved when connecting to the listener, including HTTP/1.1 and HTTP/2.

+

The HTTP/1.1 options are documented in the cowboy_http(3) manual; and the HTTP/2 options in cowboy_http2(3).

-
-
- -
+

Return value

-
-

An ok tuple is returned on success. It contains the pid of -the top-level supervisor for the listener.

-

An error tuple is returned on error. The error reason may -be any Erlang term.

-

A common error is eaddrinuse. It indicates that the port -configured for Cowboy is already in use.

-
-
-
+

An ok tuple is returned on success. It contains the pid of the top-level supervisor for the listener.

+

An error tuple is returned on error. The error reason may be any Erlang term.

+

A common error is eaddrinuse. It indicates that the port configured for Cowboy is already in use.

Changelog

-
-
    -
  • -

    -2.0: HTTP/2 support added. -

    +
    • 2.0: HTTP/2 support added.
      • -
    • -

      -2.0: Function introduced. Replaces cowboy:start_https/4. -

      +
    • 2.0: Function introduced. Replaces cowboy:start_https/4.
      • -
-
-
-
+

Examples

-
-
-
Start a listener
-
-
Dispatch = cowboy_router:compile([
-    {'_', [
-        {"/", toppage_h, []}
+
Dispatch = cowboy_router:compile([
+    {'_', [
+        {"/", toppage_h, []}
     ]}
 ]),
 
-{ok, _} = cowboy:start_tls(example, [
-    {port, 8443},
-    {cert, "path/to/cert.pem"}
+{ok, _} = cowboy:start_tls(example, [
+    {port, 8443},
+    {cert, "path/to/cert.pem"}
 ], #{
-    env => #{dispatch => Dispatch}
-}).
-
-
Start a listener on a random port
-
-
Name = example,
+
Name = example,
 
-{ok, _} = cowboy:start_tls(Name, [
-    {cert, "path/to/cert.pem"}
+{ok, _} = cowboy:start_tls(Name, [
+    {cert, "path/to/cert.pem"}
 ], #{
-    env => #{dispatch => Dispatch}
+    env => #{dispatch => Dispatch}
 }),
 
-Port = ranch:get_port(Name).
-
-
-
+Port = ranch:get_port(Name). +

See also

-
-

cowboy(3), -cowboy:start_clear(3), -cowboy:stop_listener(3), -ranch(3)

-
- +

cowboy(3), cowboy:start_clear(3), cowboy:stop_listener(3), ranch(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy.stop_listener/index.html b/docs/en/cowboy/2.3/manual/cowboy.stop_listener/index.html index 0fc6df10..8fbdeef2 100644 --- a/docs/en/cowboy/2.3/manual/cowboy.stop_listener/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy.stop_listener/index.html @@ -62,87 +62,42 @@

cowboy:stop_listener(3)

-

Name

-
-

cowboy:stop_listener - Stop the given listener

-
-
-
+

cowboy:stop_listener - Stop the given listener

Description

-
-
-
-
stop_listener(Name :: ranch:ref())
-    -> ok | {error, not_found}.
-

Stop a previously started listener.

-

Alias of ranch:stop_listener(3).

-
-
-
+
stop_listener(Name :: ranch:ref())
+    -> ok | {error, not_found}.
+
+

Stop a previously started listener.

+

Alias of ranch:stop_listener(3).

Arguments

-
-
-
-Name -
-
-

-The name of the listener to be stopped. -

-

The name of the listener is the first argument given to the -cowboy:start_clear(3), -cowboy:start_tls(3) or -ranch:start_listener(3) function.

+
Name
+

The name of the listener to be stopped.

+

The name of the listener is the first argument given to the cowboy:start_clear(3), cowboy:start_tls(3) or ranch:start_listener(3) function.

-
-
- -
+

Return value

-
-

The atom ok is returned on success.

-

The {error, not_found} tuple is returned when the listener -does not exist.

-
-
-
+

The atom ok is returned on success.

+

The {error, not_found} tuple is returned when the listener does not exist.

Changelog

-
-
    -
  • -

    -1.0: Function introduced. -

    +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Stop a listener
-
-
ok = cowboy:stop_listener(example).
-
-
-
+
ok = cowboy:stop_listener(example).
+

See also

-
-

cowboy(3), -cowboy:start_clear(3), -cowboy:start_tls(3), -ranch(3), -ranch:start_listener(3)

-
- +

cowboy(3), cowboy:start_clear(3), cowboy:start_tls(3), ranch(3), ranch:start_listener(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy/index.html b/docs/en/cowboy/2.3/manual/cowboy/index.html index 0b551dfa..9ea56c9e 100644 --- a/docs/en/cowboy/2.3/manual/cowboy/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy/index.html @@ -62,129 +62,76 @@

cowboy(3)

-

Name

-
-

cowboy - HTTP server

-
-
-
+

cowboy - HTTP server

Description

-
-

The module cowboy provides convenience functions for -manipulating Ranch listeners.

-
-
-
+

The module cowboy provides convenience functions for manipulating Ranch listeners.

Exports

-
-
-
-
-
+

Types

-
-

fields()

-
-
-
fields() :: [Name
-           | {Name, Constraints}
-           | {Name, Constraints, Default}]
-
-Name        :: atom()
-Constraints :: Constraint | [Constraint]
-Constraint  :: cowboy_constraints:constraint()
-Default     :: any()
-

Fields description for match operations.

-

This type is used in cowboy_router(3) -for matching bindings and in the match functions found in -cowboy_req(3).

-
-
+
fields() :: [Name
+           | {Name, Constraints}
+           | {Name, Constraints, Default}]
+
+Name        :: atom()
+Constraints :: Constraint | [Constraint]
+Constraint  :: cowboy_constraints:constraint()
+Default     :: any()
+
+

Fields description for match operations.

+

This type is used in cowboy_router(3) for matching bindings and in the match functions found in cowboy_req(3).

http_headers()

-
-
-
http_headers() :: #{binary() => iodata()}
-

HTTP headers.

-
-
+
http_headers() :: #{binary() => iodata()}
+
+

HTTP headers.

http_status()

-
-
-
http_status() :: non_neg_integer() | binary()
-

HTTP response status.

-

A binary status can be used to set a reason phrase. Note -however that HTTP/2 only sends the status code and drops -the reason phrase entirely.

- -
+
http_status() :: non_neg_integer() | binary()
+
+

HTTP response status.

+

A binary status can be used to set a reason phrase. Note however that HTTP/2 only sends the status code and drops the reason phrase entirely.

http_version()

-
-
-
http_version() :: 'HTTP/2' | 'HTTP/1.1' | 'HTTP/1.0'
-

HTTP version.

-

Note that semantically, HTTP/1.1 and HTTP/2 are equivalent.

- -
+
http_version() :: 'HTTP/2' | 'HTTP/1.1' | 'HTTP/1.0'
+
+

HTTP version.

+

Note that semantically, HTTP/1.1 and HTTP/2 are equivalent.

opts()

-
-
-
opts() :: map()
-

Options for the HTTP/1.1, HTTP/2 and Websocket protocols.

-

The protocol options are in a map containing all the options for -the different protocols that may be involved when connecting -to the listener, including HTTP/1.1 and HTTP/2.

-

The HTTP/1.1 options are documented in the -cowboy_http(3) manual -and the HTTP/2 options in -cowboy_http2(3).

- - - -
+
opts() :: map()
+
+

Options for the HTTP/1.1, HTTP/2 and Websocket protocols.

+

The protocol options are in a map containing all the options for the different protocols that may be involved when connecting to the listener, including HTTP/1.1 and HTTP/2.

+

The HTTP/1.1 options are documented in the cowboy_http(3) manual and the HTTP/2 options in cowboy_http2(3).

See also

-
-

cowboy(7), -ranch(3)

-
- +

cowboy(7), ranch(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_app/index.html b/docs/en/cowboy/2.3/manual/cowboy_app/index.html index 906a1178..9512bd6a 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_app/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_app/index.html @@ -62,171 +62,77 @@

cowboy(7)

-

Name

-
-

cowboy - Small, fast, modern HTTP server for Erlang/OTP

-
-
-
+

cowboy - Small, fast, modern HTTP server for Erlang/OTP

Description

-
-

Cowboy is an HTTP server for Erlang/OTP with support for the -HTTP/1.1, HTTP/2 and Websocket protocols.

-

Cowboy aims to provide a complete HTTP stack. This includes -the implementation of the HTTP RFCs but also any directly -related standards, like Websocket or Server-Sent Events.

-
-
-
+

Cowboy is an HTTP server for Erlang/OTP with support for the HTTP/1.1, HTTP/2 and Websocket protocols.

+

Cowboy aims to provide a complete HTTP stack. This includes the implementation of the HTTP RFCs but also any directly related standards, like Websocket or Server-Sent Events.

Modules

-
-

Functions:

-
-

Protocols:

-
+

Protocols:

+
-

Handlers:

-
+

Handlers:

+
-

Behaviors:

-
+

Behaviors:

+
-

Middlewares:

-
+

Middlewares:

+
-
-
-
+ +

Dependencies

-
-
    -
  • -

    -ranch(7) - Socket acceptor pool for TCP protocols -

    +
    • ranch(7) - Socket acceptor pool for TCP protocols
      • -
    • -

      -cowlib(7) - Support library for manipulating Web protocols -

      +
    • cowlib(7) - Support library for manipulating Web protocols
      • -
    • -

      -ssl - Secure communication over sockets -

      +
    • ssl - Secure communication over sockets
      • -
    • -

      -crypto - Crypto functions -

      +
    • crypto - Crypto functions
      • -
-

All these applications must be started before the cowboy -application. To start Cowboy and all dependencies at once:

-
-
-
{ok, _} = application:ensure_all_started(cowboy).
-
-
-
+
{ok, _} = application:ensure_all_started(cowboy).
+

Environment

-
-

The cowboy application does not define any application -environment configuration parameters.

-
- -
+

The cowboy application does not define any application environment configuration parameters.

See also

-
-

ranch(7), -cowlib(7)

-
-
+

ranch(7), cowlib(7)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_constraints.int/index.html b/docs/en/cowboy/2.3/manual/cowboy_constraints.int/index.html index 6153fcbf..67a2c938 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_constraints.int/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_constraints.int/index.html @@ -62,92 +62,52 @@

cowboy_constraints:int(3)

-

Name

-
-

cowboy_constraints:int - Integer constraint

-
-
-
+

cowboy_constraints:int - Integer constraint

Description

-
-

Constraint functions implement a number of different operations.

-
-
-
int(forward, Bin) -> {ok, Int} | {error, not_an_integer}
+
int(forward, Bin) -> {ok, Int} | {error, not_an_integer}
 
-Bin :: binary()
-Int :: integer()
-

Validate and convert the text representation of an integer.

-
-
-
int(reverse, Int) -> {ok, Bin} | {error, not_an_integer}
-

Convert an integer back to its text representation.

-
-
-
int(format_error, Error) -> HumanReadable
+
int(format_error, Error) -> HumanReadable
 
-Error         :: {not_an_integer, Bin | Int}
-HumanReadable :: iolist()
-

Generate a human-readable error message.

-
-
-
+Error :: {not_an_integer, Bin | Int} +HumanReadable :: iolist() +
+

Generate a human-readable error message.

Arguments

-
-

Arguments vary depending on the operation. Constraint -functions always take the operation type as first argument, -and the value as second argument.

-
- -
+

Arguments vary depending on the operation. Constraint functions always take the operation type as first argument, and the value as second argument.

Return value

-
-

The return value varies depending on the operation.

-
-
-
+

The return value varies depending on the operation.

Changelog

-
-
    -
  • -

    -2.0: Interface modified to allow for a variety of operations. -

    +
    • 2.0: Interface modified to allow for a variety of operations.
      • -
    • -

      -1.0: Constraint introduced. -

      +
    • 1.0: Constraint introduced.
      • -
-
-
-
+

Examples

-
-

This function is not meant to be called directly.

-
-
-
+

This function is not meant to be called directly.

See also

-
-

cowboy_constraints(3), -cowboy_constraints:nonempty(3), -cowboy_router(3), -cowboy_req:match_cookies(3), -cowboy_req:match_qs(3)

-
-
+

cowboy_constraints(3), cowboy_constraints:nonempty(3), cowboy_router(3), cowboy_req:match_cookies(3), cowboy_req:match_qs(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_constraints.nonempty/index.html b/docs/en/cowboy/2.3/manual/cowboy_constraints.nonempty/index.html index cc14ce3c..8578be2c 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_constraints.nonempty/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_constraints.nonempty/index.html @@ -62,91 +62,51 @@

cowboy_constraints:nonempty(3)

-

Name

-
-

cowboy_constraints:nonempty - Non-empty constraint

-
-
-
+

cowboy_constraints:nonempty - Non-empty constraint

Description

-
-

Constraint functions implement a number of different operations.

-
-
-
nonempty(forward | reverse, <<>>) -> {error, empty}
-

Reject empty values.

-
-
-
nonempty(forward | reverse, Bin) -> {ok, Bin}
+
nonempty(forward | reverse, Bin) -> {ok, Bin}
 
-Bin :: binary()
-

Accept any other binary values.

-
-
-
nonempty(format_error, Error) -> HumanReadable
+
nonempty(format_error, Error) -> HumanReadable
 
-Error         :: {empty, Bin}
-HumanReadable :: iolist()
-

Generate a human-readable error message.

-
-
-
+Error :: {empty, Bin} +HumanReadable :: iolist() +
+

Generate a human-readable error message.

Arguments

-
-

Arguments vary depending on the operation. Constraint -functions always take the operation type as first argument, -and the value as second argument.

-
- -
+

Arguments vary depending on the operation. Constraint functions always take the operation type as first argument, and the value as second argument.

Return value

-
-

The return value varies depending on the operation.

-
-
-
+

The return value varies depending on the operation.

Changelog

-
-
    -
  • -

    -2.0: Interface modified to allow for a variety of operations. -

    +
    • 2.0: Interface modified to allow for a variety of operations.
      • -
    • -

      -1.0: Constraint introduced. -

      +
    • 1.0: Constraint introduced.
      • -
-
-
-
+

Examples

-
-

This function is not meant to be called directly.

-
-
-
+

This function is not meant to be called directly.

See also

-
-

cowboy_constraints(3), -cowboy_constraints:int(3), -cowboy_router(3), -cowboy_req:match_cookies(3), -cowboy_req:match_qs(3)

-
-
+

cowboy_constraints(3), cowboy_constraints:int(3), cowboy_router(3), cowboy_req:match_cookies(3), cowboy_req:match_qs(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_constraints/index.html b/docs/en/cowboy/2.3/manual/cowboy_constraints/index.html index 6de9597b..8f0ebbbf 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_constraints/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_constraints/index.html @@ -62,84 +62,43 @@

cowboy_constraints(3)

-

Name

-
-

cowboy_constraints - Constraints

-
-
-
+

cowboy_constraints - Constraints

Description

-
-

The module cowboy_constraints defines the built-in -constraints in Cowboy and provides an interface for -manipulating these constraints.

-

Constraints are functions that define what type of -input is allowed. They are used throughout Cowboy, -from the router to query strings to cookies.

-
-
-
+

The module cowboy_constraints defines the built-in constraints in Cowboy and provides an interface for manipulating these constraints.

+

Constraints are functions that define what type of input is allowed. They are used throughout Cowboy, from the router to query strings to cookies.

Exports

-
-

Built-in constraints:

-
-
-
-
+

Types

-
-

constraint()

-
-
-
constraint() :: int | nonempty | fun()
-

A constraint function.

-

The atom constraints are built-in, see the corresponding -function in the exports list above.

-
-
+
constraint() :: int | nonempty | fun()
+
+

A constraint function.

+

The atom constraints are built-in, see the corresponding function in the exports list above.

reason()

-
-
-
reason() :: {constraint(), Reason, Value}
-
-Reason :: any()
-Value  :: any()
-

Reason for the constraint failure.

-

It includes the constraint function in question, -a machine-readable error reason and the value that -made the constraint fail.

-
- - -
+
reason() :: {constraint(), Reason, Value}
+
+Reason :: any()
+Value  :: any()
+
+

Reason for the constraint failure.

+

It includes the constraint function in question, a machine-readable error reason and the value that made the constraint fail.

See also

-
-

cowboy(7), -cowboy(3), -cowboy_router(3), -cowboy_req:match_cookies(3), -cowboy_req:match_qs(3)

-
- +

cowboy(7), cowboy(3), cowboy_router(3), cowboy_req:match_cookies(3), cowboy_req:match_qs(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_handler.terminate/index.html b/docs/en/cowboy/2.3/manual/cowboy_handler.terminate/index.html index dd9d24f4..c1050fa3 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_handler.terminate/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_handler.terminate/index.html @@ -62,109 +62,54 @@

cowboy_handler:terminate(3)

-

Name

-
-

cowboy_handler:terminate - Terminate the handler

-
-
-
+

cowboy_handler:terminate - Terminate the handler

Description

-
-
-
-
terminate(Reason, PartialReq, State, Handler) -> ok
-
-Reason     :: any()
-PartialReq :: map()
-State      :: any()
-Handler    :: module()
-

Call the optional terminate callback if it is defined.

-

Make sure to use this function at the end of the execution -of modules that implement custom handler behaviors.

-
-
-
+
terminate(Reason, PartialReq, State, Handler) -> ok
+
+Reason     :: any()
+PartialReq :: map()
+State      :: any()
+Handler    :: module()
+
+

Call the optional terminate callback if it is defined.

+

Make sure to use this function at the end of the execution of modules that implement custom handler behaviors.

Arguments

-
-
-
-Reason -
-
-

-Reason for termination. -

+
Reason
+

Reason for termination.

-
-PartialReq -
-
-

-The Req object. -

-

It is possible to remove fields from the Req object to save memory -when the handler has no concept of requests/responses. The only -requirement is that a map is provided.

+
PartialReq
+

The Req object.

+

It is possible to remove fields from the Req object to save memory when the handler has no concept of requests/responses. The only requirement is that a map is provided.

-
-State -
-
-

-Handler state. -

+
State
+

Handler state.

-
-Handler -
-
-

-Handler module. -

+
Handler
+

Handler module.

-
-
- -
+

Return value

-
-

The atom ok is always returned. It can be safely ignored.

-
-
-
+

The atom ok is always returned. It can be safely ignored.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. -

    +
    • 2.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Terminate a handler normally
-
-
cowboy_handler:terminate(normal, Req, State, Handler).
-
-
-
+
cowboy_handler:terminate(normal, Req, State, Handler).
+

See also

-
-

cowboy_handler(3)

-
- +

cowboy_handler(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_handler/index.html b/docs/en/cowboy/2.3/manual/cowboy_handler/index.html index 88eed6c6..def10074 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_handler/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_handler/index.html @@ -62,96 +62,46 @@

cowboy_handler(3)

-

Name

-
-

cowboy_handler - Plain HTTP handlers

-
-
-
+

cowboy_handler - Plain HTTP handlers

Description

-
-

The cowboy_handler middleware executes the handler selected -by the router or any other preceding middleware.

-

This middleware takes the handler module and initial state -from the handler and handler_opts environment values, -respectively. On completion, it adds a result value to -the middleware environment, containing the return value -of the terminate/3 callback (if defined) and ok otherwise.

-

This module also defines a callback interface for handling -HTTP requests.

-
-
-
+

The cowboy_handler middleware executes the handler selected by the router or any other preceding middleware.

+

This middleware takes the handler module and initial state from the handler and handler_opts environment values, respectively. On completion, it adds a result value to the middleware environment, containing the return value of the terminate/3 callback (if defined) and ok otherwise.

+

This module also defines a callback interface for handling HTTP requests.

Callbacks

-
-

Plain HTTP handlers implement the following interface:

-
-
-
init(Req, State) -> {ok, Req, State}
-
-terminate(Reason, Req, State) -> ok  %% optional
-
-Req    :: cowboy_req:req()
-State  :: any()
-Reason :: normal
-        | {crash, error | exit | throw, any()}
-

These two callbacks are common to all handlers.

-

Plain HTTP handlers do all their work in the init/2 -callback. Returning ok terminates the handler. If no -response is sent, Cowboy will send a 204 No Content.

-

The optional terminate/3 callback will ultimately be called -with the reason for the termination of the handler. -Cowboy will terminate the process right after this. There -is no need to perform any cleanup in this callback.

-

The following terminate reasons are defined for plain HTTP -handlers:

-
-
-normal -
-
-

- The connection was closed normally. -

+
init(Req, State) -> {ok, Req, State}
+
+terminate(Reason, Req, State) -> ok  %% optional
+
+Req    :: cowboy_req:req()
+State  :: any()
+Reason :: normal
+        | {crash, error | exit | throw, any()}
+
+

These two callbacks are common to all handlers.

+

Plain HTTP handlers do all their work in the init/2 callback. Returning ok terminates the handler. If no response is sent, Cowboy will send a 204 No Content.

+

The optional terminate/3 callback will ultimately be called with the reason for the termination of the handler. Cowboy will terminate the process right after this. There is no need to perform any cleanup in this callback.

+

The following terminate reasons are defined for plain HTTP handlers:

+
normal
+

The connection was closed normally.

-
-{crash, Class, Reason} -
-
-

- A crash occurred in the handler. Class and Reason can be - used to obtain more information about the crash. The function - erlang:get_stacktrace/0 can also be called to obtain the - stacktrace of the process when the crash occurred. -

+
{crash, Class, Reason}
+

A crash occurred in the handler. Class and Reason can be used to obtain more information about the crash. The function erlang:get_stacktrace/0 can also be called to obtain the stacktrace of the process when the crash occurred.

-
- - -
+

Exports

-
-

The following function should be called by modules implementing -custom handlers to execute the optional terminate callback:

-
-
-
-
+

See also

-
-

cowboy(7)

-
-
+

cowboy(7)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_http/index.html b/docs/en/cowboy/2.3/manual/cowboy_http/index.html index 12b29e27..4268bfef 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_http/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_http/index.html @@ -62,255 +62,116 @@

cowboy_http(3)

-

Name

-
-

cowboy_http - HTTP/1.1

-
-
-
+

cowboy_http - HTTP/1.1

Description

-
-

The module cowboy_http implements HTTP/1.1 and HTTP/1.0 -as a Ranch protocol.

-
-
-
+

The module cowboy_http implements HTTP/1.1 and HTTP/1.0 as a Ranch protocol.

Options

-
-
-
+ +
-
opts() :: #{
-    connection_type         => worker | supervisor,
-    env                     => cowboy_middleware:env(),
-    idle_timeout            => timeout(),
-    inactivity_timeout      => timeout(),
-    max_empty_lines         => non_neg_integer(),
-    max_header_name_length  => non_neg_integer(),
-    max_header_value_length => non_neg_integer(),
-    max_headers             => non_neg_integer(),
-    max_keepalive           => non_neg_integer(),
-    max_method_length       => non_neg_integer(),
-    max_request_line_length => non_neg_integer(),
-    max_skip_body_length    => non_neg_integer(),
-    middlewares             => [module()],
-    request_timeout         => timeout(),
-    shutdown_timeout        => timeout(),
-    stream_handlers         => [module()]
-}
-

Configuration for the HTTP/1.1 protocol.

-

This configuration is passed to Cowboy when starting listeners -using cowboy:start_clear/3 or cowboy:start_tls/3 functions.

-

It can be updated without restarting listeners using the -Ranch functions ranch:get_protocol_options/1 and -ranch:set_protocol_options/2.

-

The default value is given next to the option name:

-
-
-connection_type (supervisor) -
-
-

- Whether the connection process also acts as a supervisor. -

-
-
-env (#{}) -
-
-

- Middleware environment. -

-
-
-idle_timeout (60000) -
-
-

- Time in ms with no data received before Cowboy closes the connection. -

-
-
-inactivity_timeout (300000) -
-
-

- Time in ms with nothing received at all before Cowboy closes the connection. -

-
-
-max_empty_lines (5) -
-
-

- Maximum number of empty lines before a request. -

-
-
-max_header_name_length (64) -
-
-

- Maximum length of header names. -

-
-
-max_header_value_length (4096) -
-
-

- Maximum length of header values. -

-
-
-max_headers (100) -
-
-

- Maximum number of headers allowed per request. -

-
-
-max_keepalive (100) -
-
-

- Maximum number of requests allowed per connection. -

-
-
-max_method_length (32) -
-
-

- Maximum length of the method. -

-
-
-max_request_line_length (8000) -
-
-

- Maximum length of the request line. -

-
-
-max_skip_body_length (1000000) -
-
-

- Maximum length Cowboy is willing to skip when the user code did not read the body fully. - When the remaining length is too large or unknown Cowboy will close the connection. -

-
-
-middlewares ([cowboy_router, cowboy_handler]) -
-
-

- Middlewares to run for every request. -

-
-
-request_timeout (5000) -
-
-

- Time in ms with no requests before Cowboy closes the connection. -

-
-
-shutdown_timeout (5000) -
-
-

- Time in ms Cowboy will wait for child processes to shut down before killing them. -

-
-
-stream_handlers ([cowboy_stream_h]) -
-
-

- Ordered list of stream handlers that will handle all stream events. -

-
-
-
-
-
+
opts() :: #{
+    connection_type         => worker | supervisor,
+    env                     => cowboy_middleware:env(),
+    idle_timeout            => timeout(),
+    inactivity_timeout      => timeout(),
+    max_empty_lines         => non_neg_integer(),
+    max_header_name_length  => non_neg_integer(),
+    max_header_value_length => non_neg_integer(),
+    max_headers             => non_neg_integer(),
+    max_keepalive           => non_neg_integer(),
+    max_method_length       => non_neg_integer(),
+    max_request_line_length => non_neg_integer(),
+    max_skip_body_length    => non_neg_integer(),
+    middlewares             => [module()],
+    request_timeout         => timeout(),
+    shutdown_timeout        => timeout(),
+    stream_handlers         => [module()]
+}
+
+

Configuration for the HTTP/1.1 protocol.

+

This configuration is passed to Cowboy when starting listeners using cowboy:start_clear/3 or cowboy:start_tls/3 functions.

+

It can be updated without restarting listeners using the Ranch functions ranch:get_protocol_options/1 and ranch:set_protocol_options/2.

+

The default value is given next to the option name:

+
connection_type (supervisor)
+

Whether the connection process also acts as a supervisor.

+
+
env (#{})
+

Middleware environment.

+
+
idle_timeout (60000)
+

Time in ms with no data received before Cowboy closes the connection.

+
+
inactivity_timeout (300000)
+

Time in ms with nothing received at all before Cowboy closes the connection.

+
+
max_empty_lines (5)
+

Maximum number of empty lines before a request.

+
+
max_header_name_length (64)
+

Maximum length of header names.

+
+
max_header_value_length (4096)
+

Maximum length of header values.

+
+
max_headers (100)
+

Maximum number of headers allowed per request.

+
+
max_keepalive (100)
+

Maximum number of requests allowed per connection.

+
+
max_method_length (32)
+

Maximum length of the method.

+
+
max_request_line_length (8000)
+

Maximum length of the request line.

+
+
max_skip_body_length (1000000)
+

Maximum length Cowboy is willing to skip when the user code did not read the body fully. When the remaining length is too large or unknown Cowboy will close the connection.

+
+
middlewares ([cowboy_router, cowboy_handler])
+

Middlewares to run for every request.

+
+
request_timeout (5000)
+

Time in ms with no requests before Cowboy closes the connection.

+
+
shutdown_timeout (5000)
+

Time in ms Cowboy will wait for child processes to shut down before killing them.

+
+
stream_handlers ([cowboy_stream_h])
+

Ordered list of stream handlers that will handle all stream events.

+
+

Changelog

-
-
    -
  • -

    -2.2: The max_skip_body_length option was added. -

    +
    • 2.2: The max_skip_body_length option was added.
      • -
    • -

      -2.0: The timeout option was renamed request_timeout. -

      +
    • 2.0: The timeout option was renamed request_timeout.
      • -
    • -

      -2.0: The idle_timeout, inactivity_timeout and shutdown_timeout options were added. -

      +
    • 2.0: The idle_timeout, inactivity_timeout and shutdown_timeout options were added.
      • -
    • -

      -2.0: The max_method_length option was added. -

      +
    • 2.0: The max_method_length option was added.
      • -
    • -

      -2.0: The max_request_line_length default was increased from 4096 to 8000. -

      +
    • 2.0: The max_request_line_length default was increased from 4096 to 8000.
      • -
    • -

      -2.0: The connection_type option was added. -

      +
    • 2.0: The connection_type option was added.
      • -
    • -

      -2.0: The env option is now a map instead of a proplist. -

      +
    • 2.0: The env option is now a map instead of a proplist.
      • -
    • -

      -2.0: The stream_handlers option was added. -

      +
    • 2.0: The stream_handlers option was added.
      • -
    • -

      -2.0: The compress option was removed in favor of the cowboy_compress_h stream handler. -

      +
    • 2.0: The compress option was removed in favor of the cowboy_compress_h stream handler.
      • -
    • -

      -2.0: Options are now a map instead of a proplist. -

      +
    • 2.0: Options are now a map instead of a proplist.
      • -
    • -

      -2.0: Protocol introduced. Replaces cowboy_protocol. -

      +
    • 2.0: Protocol introduced. Replaces cowboy_protocol.
      • -
-
-
-
+

See also

-
-

cowboy(7), -cowboy_http2(3), -cowboy_websocket(3)

-
-
+

cowboy(7), cowboy_http2(3), cowboy_websocket(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_http2/index.html b/docs/en/cowboy/2.3/manual/cowboy_http2/index.html index 90954f46..dd72ba7f 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_http2/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_http2/index.html @@ -62,123 +62,60 @@

cowboy_http2(3)

-

Name

-
-

cowboy_http2 - HTTP/2

-
-
-
+

cowboy_http2 - HTTP/2

Description

-
-

The module cowboy_http2 implements HTTP/2 -as a Ranch protocol.

-
-
-
+

The module cowboy_http2 implements HTTP/2 as a Ranch protocol.

Options

-
-
-
+ +
-
opts() :: #{
-    connection_type    => worker | supervisor,
-    env                => cowboy_middleware:env(),
-    inactivity_timeout => timeout(),
-    middlewares        => [module()],
-    preface_timeout    => timeout(),
-    shutdown_timeout   => timeout(),
-    stream_handlers    => [module()]
-}
-

Configuration for the HTTP/2 protocol.

-

This configuration is passed to Cowboy when starting listeners -using cowboy:start_clear/3 or cowboy:start_tls/3 functions.

-

It can be updated without restarting listeners using the -Ranch functions ranch:get_protocol_options/1 and -ranch:set_protocol_options/2.

-

The default value is given next to the option name:

-
-
-connection_type (supervisor) -
-
-

- Whether the connection process also acts as a supervisor. -

+
opts() :: #{
+    connection_type    => worker | supervisor,
+    env                => cowboy_middleware:env(),
+    inactivity_timeout => timeout(),
+    middlewares        => [module()],
+    preface_timeout    => timeout(),
+    shutdown_timeout   => timeout(),
+    stream_handlers    => [module()]
+}
+
+

Configuration for the HTTP/2 protocol.

+

This configuration is passed to Cowboy when starting listeners using cowboy:start_clear/3 or cowboy:start_tls/3 functions.

+

It can be updated without restarting listeners using the Ranch functions ranch:get_protocol_options/1 and ranch:set_protocol_options/2.

+

The default value is given next to the option name:

+
connection_type (supervisor)
+

Whether the connection process also acts as a supervisor.

-
-env (#{}) -
-
-

- Middleware environment. -

+
env (#{})
+

Middleware environment.

-
-inactivity_timeout (300000) -
-
-

- Time in ms with nothing received at all before Cowboy closes the connection. -

+
inactivity_timeout (300000)
+

Time in ms with nothing received at all before Cowboy closes the connection.

-
-middlewares ([cowboy_router, cowboy_handler]) -
-
-

- Middlewares to run for every request. -

+
middlewares ([cowboy_router, cowboy_handler])
+

Middlewares to run for every request.

-
-preface_timeout (5000) -
-
-

- Time in ms Cowboy is willing to wait for the connection preface. -

+
preface_timeout (5000)
+

Time in ms Cowboy is willing to wait for the connection preface.

-
-shutdown_timeout (5000) -
-
-

- Time in ms Cowboy will wait for child processes to shut down before killing them. -

+
shutdown_timeout (5000)
+

Time in ms Cowboy will wait for child processes to shut down before killing them.

-
-stream_handlers ([cowboy_stream_h]) -
-
-

- Ordered list of stream handlers that will handle all stream events. -

+
stream_handlers ([cowboy_stream_h])
+

Ordered list of stream handlers that will handle all stream events.

-
-
-
-
+

Changelog

-
-
    -
  • -

    -2.0: Protocol introduced. -

    +
    • 2.0: Protocol introduced.
      • -
-
-
-
+

See also

-
-

cowboy(7), -cowboy_http(3), -cowboy_websocket(3)

-
-
+

cowboy(7), cowboy_http(3), cowboy_websocket(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_loop/index.html b/docs/en/cowboy/2.3/manual/cowboy_loop/index.html index 2b9b57ff..d4e2f459 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_loop/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_loop/index.html @@ -62,120 +62,60 @@

cowboy_loop(3)

-

Name

-
-

cowboy_loop - Loop handlers

-
-
-
+

cowboy_loop - Loop handlers

Description

-
-

The module cowboy_loop defines a callback interface for -long running HTTP connections.

-

You should switch to this behavior for long polling, -server-sent events and similar long-running requests.

-

There are generally two usage patterns:

-
    -
  • -

    -Loop until receiving a specific message, then send - a response and stop execution (for example long polling); -

    +

    The module cowboy_loop defines a callback interface for long running HTTP connections.

    +

    You should switch to this behavior for long polling, server-sent events and similar long-running requests.

    +

    There are generally two usage patterns:

    +
    • Loop until receiving a specific message, then send a response and stop execution (for example long polling);
      • -
    • -

      -Or initiate a response in init/2 and stream the - body in info/3 as necessary (for example server-sent events). -

      +
    • Or initiate a response in init/2 and stream the body in info/3 as necessary (for example server-sent events).
      • -
-
-
-
+

Callbacks

-
-

Loop handlers implement the following interface:

-
-
-
init(Req, State)
-    -> {cowboy_loop, Req, State}
-     | {cowboy_loop, Req, State, hibernate}
-
-info(Info, Req, State)
-    -> {ok, Req, State}
-     | {ok, Req, State, hibernate}
-     | {stop, Req, State}
-
-terminate(Reason, Req, State) -> ok  %% optional
-
-Req    :: cowboy_req:req()
-State  :: any()
-Info   :: any()
-Reason :: stop
-        | {crash, error | exit | throw, any()}
-

The init/2 callback is common to all handlers. To switch -to the loop behavior, it must return cowboy_loop as the -first element of the tuple.

-

The info/3 callback will be called for every Erlang message -received. It may choose to continue the receive loop or stop -it.

-

The optional terminate/3 callback will ultimately be called -with the reason for the termination of the handler. -Cowboy will terminate the process right after this. There -is no need to perform any cleanup in this callback.

-

The following terminate reasons are defined for loop handlers:

-
-
-stop -
-
-

- The handler requested to close the connection by returning - a stop tuple. -

+
init(Req, State)
+    -> {cowboy_loop, Req, State}
+     | {cowboy_loop, Req, State, hibernate}
+
+info(Info, Req, State)
+    -> {ok, Req, State}
+     | {ok, Req, State, hibernate}
+     | {stop, Req, State}
+
+terminate(Reason, Req, State) -> ok  %% optional
+
+Req    :: cowboy_req:req()
+State  :: any()
+Info   :: any()
+Reason :: stop
+        | {crash, error | exit | throw, any()}
+
+

The init/2 callback is common to all handlers. To switch to the loop behavior, it must return cowboy_loop as the first element of the tuple.

+

The info/3 callback will be called for every Erlang message received. It may choose to continue the receive loop or stop it.

+

The optional terminate/3 callback will ultimately be called with the reason for the termination of the handler. Cowboy will terminate the process right after this. There is no need to perform any cleanup in this callback.

+

The following terminate reasons are defined for loop handlers:

+
stop
+

The handler requested to close the connection by returning a stop tuple.

-
-{crash, Class, Reason} -
-
-

- A crash occurred in the handler. Class and Reason can be - used to obtain more information about the crash. The function - erlang:get_stacktrace/0 can also be called to obtain the - stacktrace of the process when the crash occurred. -

+
{crash, Class, Reason}
+

A crash occurred in the handler. Class and Reason can be used to obtain more information about the crash. The function erlang:get_stacktrace/0 can also be called to obtain the stacktrace of the process when the crash occurred.

-
- - -
+

Changelog

-
-
    -
  • -

    -2.0: Loop handlers no longer need to handle overflow/timeouts. -

    +
    • 2.0: Loop handlers no longer need to handle overflow/timeouts.
      • -
    • -

      -1.0: Behavior introduced. -

      +
    • 1.0: Behavior introduced.
      • -
-
-
-
+

See also

-
-

cowboy(7), -cowboy_handler(3)

-
-
+

cowboy(7), cowboy_handler(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_middleware/index.html b/docs/en/cowboy/2.3/manual/cowboy_middleware/index.html index 200af7f6..7dc3e2bf 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_middleware/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_middleware/index.html @@ -62,115 +62,56 @@

cowboy_middleware(3)

-

Name

-
-

cowboy_middleware - Middlewares

-
-
-
+

cowboy_middleware - Middlewares

Description

-
-

The module cowboy_middleware defines a callback interface for -Cowboy middlewares.

-

Middlewares process the request sequentially in the order they -are configured.

-
-
-
+

The module cowboy_middleware defines a callback interface for Cowboy middlewares.

+

Middlewares process the request sequentially in the order they are configured.

Callbacks

-
-

Middlewares implement the following interface:

-
-
-
execute(Req, Env)
-    -> {ok, Req, Env}
-     | {suspend, module(), atom(), [any()]}
-     | {stop, Req}
-
-Req :: cowboy_req:req()
-Env :: cowboy_middleware:env()
-

The execute/2 is the only callback that needs to be -implemented. It must execute the middleware and return -with instructions for Cowboy.

-
-
-ok -
-
-

-Cowboy should continue processing the request using the -returned Req object and environment. -

+
execute(Req, Env)
+    -> {ok, Req, Env}
+     | {suspend, module(), atom(), [any()]}
+     | {stop, Req}
+
+Req :: cowboy_req:req()
+Env :: cowboy_middleware:env()
+
+

The execute/2 is the only callback that needs to be implemented. It must execute the middleware and return with instructions for Cowboy.

+
ok
+

Cowboy should continue processing the request using the returned Req object and environment.

-
-suspend -
-
-

-Cowboy will hibernate the process. When resuming, Cowboy -will apply the returned module, function and arguments. -

+
suspend
+

Cowboy will hibernate the process. When resuming, Cowboy will apply the returned module, function and arguments.

-
-stop -
-
-

-Cowboy will stop middleware execution. No other middleware -will be executed. This effectively ends the processing of -the request. -

+
stop
+

Cowboy will stop middleware execution. No other middleware will be executed. This effectively ends the processing of the request.

-
- - -
+

Types

-
-

env()

-
-
-
env() :: #{atom() => any()}
-

Middleware environment.

-

A new environment is created for every request. The initial -environment contained the user configured environment values -(like dispatch for example) plus the listener value which -contains the name of the listener for this connection.

-

Middlewares may modify the environment as necessary.

-
-
-
-
+
env() :: #{atom() => any()}
+
+

Middleware environment.

+

A new environment is created for every request. The initial environment contained the user configured environment values (like dispatch for example) plus the listener value which contains the name of the listener for this connection.

+

Middlewares may modify the environment as necessary.

Changelog

-
-
    -
  • -

    -2.0: The env type is now a map instead of a proplist. -

    +
    • 2.0: The env type is now a map instead of a proplist.
      • -
    • -

      -1.0: Behavior introduced. -

      +
    • 1.0: Behavior introduced.
      • -
-
- -
+

See also

-
-

cowboy(7)

-
-
+

cowboy(7)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.binding/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.binding/index.html index 16e29645..46822b72 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.binding/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.binding/index.html @@ -62,116 +62,60 @@

cowboy_req:binding(3)

-

Name

-
-

cowboy_req:binding - Access a value bound from the route

-
-
-
+

cowboy_req:binding - Access a value bound from the route

Description

-
-
-
-
binding(Name, Req)          -> binding(Name, Req, undefined)
-binding(Name, Req, Default) -> any() | Default
-
-Name    :: atom()
-Req     :: cowboy_req:req()
-Default :: any()
-

Return the value for the given binding.

-
-
-
+
binding(Name, Req)          -> binding(Name, Req, undefined)
+binding(Name, Req, Default) -> any() | Default
+
+Name    :: atom()
+Req     :: cowboy_req:req()
+Default :: any()
+
+

Return the value for the given binding.

Arguments

-
-
-
-Name -
-
-

-Desired binding name as an atom. -

+
Name
+

Desired binding name as an atom.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-Default -
-
-

-Default value returned when the binding is missing. -

+
Default
+

Default value returned when the binding is missing.

-
-
- -
+

Return value

-
-

By default the value is a case sensitive binary string, however -constraints may change the type of this value (for example -automatically converting numbers to integer).

-
-
-
+

By default the value is a case sensitive binary string, however constraints may change the type of this value (for example automatically converting numbers to integer).

Changelog

-
-
    -
  • -

    -2.0: Only the value is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the value is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the username from the path
-
-
%% Route is "/users/:user"
-Username = cowboy_req:binding(user, Req).
-
-
Get the branch name, with a default
-
-
%% Route is "/log[/:branch]"
-Branch = cowboy_req:binding(branch, Req, <<"master">>)
-
-
-
+
%% Route is "/log[/:branch]"
+Branch = cowboy_req:binding(branch, Req, <<"master">>)
+

See also

-
-

cowboy_req(3), -cowboy_req:bindings(3), -cowboy_req:host_info(3), -cowboy_req:path_info(3), -cowboy_router(3)

-
- +

cowboy_req(3), cowboy_req:bindings(3), cowboy_req:host_info(3), cowboy_req:path_info(3), cowboy_router(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.bindings/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.bindings/index.html index 8bbcd4aa..0054626b 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.bindings/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.bindings/index.html @@ -62,86 +62,40 @@

cowboy_req:bindings(3)

-

Name

-
-

cowboy_req:bindings - Access all values bound from the route

-
-
-
+

cowboy_req:bindings - Access all values bound from the route

Description

-
-
-
-
bindings(Req :: cowboy_req:req()) -> cowboy_router:bindings()
-

Return a map containing all bindings.

-
-
-
+
bindings(Req :: cowboy_req:req()) -> cowboy_router:bindings()
+
+

Return a map containing all bindings.

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

By default values are case sensitive binary strings, however -constraints may change the type of this value (for example -automatically converting numbers to integer).

-
-
-
+

By default values are case sensitive binary strings, however constraints may change the type of this value (for example automatically converting numbers to integer).

Changelog

-
-
    -
  • -

    -2.0: Only the values are returned, they are no longer wrapped in a tuple. -

    +
    • 2.0: Only the values are returned, they are no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get all bindings
-
-
Bindings = cowboy_req:bindings(Req).
-
-
-
+
Bindings = cowboy_req:bindings(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:binding(3), -cowboy_req:host_info(3), -cowboy_req:path_info(3), -cowboy_router(3)

-
- +

cowboy_req(3), cowboy_req:binding(3), cowboy_req:host_info(3), cowboy_req:path_info(3), cowboy_router(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.body_length/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.body_length/index.html index 262456a0..9818d81e 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.body_length/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.body_length/index.html @@ -62,89 +62,41 @@

cowboy_req:body_length(3)

-

Name

-
-

cowboy_req:body_length - Body length

-
-
-
+

cowboy_req:body_length - Body length

Description

-
-
-
-
body_length(Req :: cowboy_req:req()) -> undefined | non_neg_integer()
-

Return the length of the request body.

-

The length is not always known before reading the body. -In those cases Cowboy will return undefined. The body -length is available after the body has been fully read.

-
-
-
+
body_length(Req :: cowboy_req:req()) -> undefined | non_neg_integer()
+
+

Return the length of the request body.

+

The length is not always known before reading the body. In those cases Cowboy will return undefined. The body length is available after the body has been fully read.

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The length of the request body, or undefined if it is -not known.

-
-
-
+

The length of the request body, or undefined if it is not known.

Changelog

-
-
    -
  • -

    -2.0: Only the length is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the length is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the body length
-
-
Length = cowboy_req:body_length(Req).
-
-
-
+
Length = cowboy_req:body_length(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:has_body(3), -cowboy_req:read_body(3), -cowboy_req:read_urlencoded_body(3), -cowboy_req:read_part(3), -cowboy_req:read_part_body(3)

-
- +

cowboy_req(3), cowboy_req:has_body(3), cowboy_req:read_body(3), cowboy_req:read_urlencoded_body(3), cowboy_req:read_part(3), cowboy_req:read_part_body(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.cert/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.cert/index.html index e6cc2839..699bd3fe 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.cert/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.cert/index.html @@ -62,104 +62,60 @@

cowboy_req:cert(3)

-

Name

-
-

cowboy_req:cert - Client TLS certificate

-
-
-
+

cowboy_req:cert - Client TLS certificate

Description

-
-
-
-
cert(Req :: cowboy_req:req()) -> binary() | undefined
-

Return the peer’s TLS certificate.

-

Using the default configuration this function will always return -undefined. You need to explicitly configure Cowboy to request -the client certificate. To do this you need to set the verify -transport option to verify_peer:

-
-
-
{ok, _} = cowboy:start_tls(example, [
-    {port, 8443},
-    {cert, "path/to/cert.pem"},
-    {verify, verify_peer}
+
{ok, _} = cowboy:start_tls(example, [
+    {port, 8443},
+    {cert, "path/to/cert.pem"},
+    {verify, verify_peer}
 ], #{
-    env => #{dispatch => Dispatch}
-}).
-

You may also want to customize the verify_fun function. Please -consult the ssl application’s manual for more details.

-

TCP connections do not allow a certificate and this function -will therefore always return undefined.

-

The certificate can also be obtained using pattern matching:

-
-
-
#{cert := Cert} = Req.
-
-
-
+
#{cert := Cert} = Req.
+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The client TLS certificate.

-
-
-
+

The client TLS certificate.

Changelog

-
-
    -
  • -

    -2.1: Function introduced. -

    +
    • 2.1: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the client TLS certificate.
-
-
Cert = cowboy_req:cert(Req).
-
-
-
+
Cert = cowboy_req:cert(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:peer(3), -cowboy_req:sock(3)

-
- +

cowboy_req(3), cowboy_req:peer(3), cowboy_req:sock(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.delete_resp_header/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.delete_resp_header/index.html index 64cd7b63..3fbe5288 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.delete_resp_header/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.delete_resp_header/index.html @@ -62,95 +62,45 @@

cowboy_req:delete_resp_header(3)

-

Name

-
-

cowboy_req:delete_resp_header - Delete a response header

-
-
-
+

cowboy_req:delete_resp_header - Delete a response header

Description

-
-
-
-
delete_resp_header(Name, Req :: cowboy_req:req()) -> Req
+
delete_resp_header(Name, Req :: cowboy_req:req()) -> Req
 
-Name :: binary()  %% lowercase; case insensitive
-

Delete the given response header.

-

The header name must be given as a lowercase binary string. -While header names are case insensitive, Cowboy requires them -to be given as lowercase to function properly.

-
-
-
+Name :: binary() %% lowercase; case insensitive +
+

Delete the given response header.

+

The header name must be given as a lowercase binary string. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.

Arguments

-
-
-
-Name -
-
-

-Header name as a lowercase binary string. -

+
Name
+

Header name as a lowercase binary string.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

A new Req object is returned.

-

The returned Req object must be used from that point onward, -otherwise the header will still be sent in the response.

-
-
-
+

A new Req object is returned.

+

The returned Req object must be used from that point onward, otherwise the header will still be sent in the response.

Changelog

-
-
    -
  • -

    -1.0: Function introduced. -

    +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Remove the content-type header from the response
-
-
Req = cowboy_req:delete_resp_header(<<"content-type">>, Req0),
-
-
-
+
Req = cowboy_req:delete_resp_header(<<"content-type">>, Req0),
+

See also

-
-

cowboy_req(3), -cowboy_req:set_resp_header(3), -cowboy_req:set_resp_headers(3), -cowboy_req:has_resp_header(3), -cowboy_req:resp_header(3), -cowboy_req:resp_headers(3)

-
- +

cowboy_req(3), cowboy_req:set_resp_header(3), cowboy_req:set_resp_headers(3), cowboy_req:has_resp_header(3), cowboy_req:resp_header(3), cowboy_req:resp_headers(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.has_body/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.has_body/index.html index 1de52c2a..de71a7c7 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.has_body/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.has_body/index.html @@ -62,80 +62,38 @@

cowboy_req:has_body(3)

-

Name

-
-

cowboy_req:has_body - Is there a request body?

-
-
-
+

cowboy_req:has_body - Is there a request body?

Description

-
-
-
-
has_body(Req :: cowboy_req:req()) -> boolean()
-

Return whether the request has a body.

-
-
-
+
has_body(Req :: cowboy_req:req()) -> boolean()
+
+

Return whether the request has a body.

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

A boolean indicating whether the request has a body.

-
-
-
+

A boolean indicating whether the request has a body.

Changelog

-
-
    -
  • -

    -1.0: Function introduced. -

    +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Ensure the request has a body
-
-
true = cowboy_req:has_body(Req).
-
-
-
+
true = cowboy_req:has_body(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:body_length(3), -cowboy_req:read_body(3), -cowboy_req:read_urlencoded_body(3), -cowboy_req:read_part(3), -cowboy_req:read_part_body(3)

-
- +

cowboy_req(3), cowboy_req:body_length(3), cowboy_req:read_body(3), cowboy_req:read_urlencoded_body(3), cowboy_req:read_part(3), cowboy_req:read_part_body(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.has_resp_body/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.has_resp_body/index.html index 2426ed09..914ca182 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.has_resp_body/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.has_resp_body/index.html @@ -62,82 +62,43 @@

cowboy_req:has_resp_body(3)

-

Name

-
-

cowboy_req:has_resp_body - Is there a response body?

-
-
-
+

cowboy_req:has_resp_body - Is there a response body?

Description

-
-
-
-
has_resp_body(Req :: cowboy_req:req()) -> boolean()
-

Return whether a response body has been set.

-
-
-
+
has_resp_body(Req :: cowboy_req:req()) -> boolean()
+
+

Return whether a response body has been set.

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

A boolean indicating whether a response body has been set.

-

This function will return false when an empty response -body has been set.

-
-
-
+

A boolean indicating whether a response body has been set.

+

This function will return false when an empty response body has been set.

Changelog

-
-
    -
  • -

    -1.0: Function introduced. -

    +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Check whether a body has been set
-
-
false = cowboy_req:has_resp_body(Req0),
-Req1 = cowboy_req:set_resp_body(<<"Hello!">>, Req0),
-true = cowboy_req:has_resp_body(Req1),
-Req = cowboy_req:set_resp_body(<<>>, Req1),
-false = cowboy_req:has_resp_body(Req).
-
-
-
+
false = cowboy_req:has_resp_body(Req0),
+Req1 = cowboy_req:set_resp_body(<<"Hello!">>, Req0),
+true = cowboy_req:has_resp_body(Req1),
+Req = cowboy_req:set_resp_body(<<>>, Req1),
+false = cowboy_req:has_resp_body(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:set_resp_body(3)

-
- +

cowboy_req(3), cowboy_req:set_resp_body(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.has_resp_header/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.has_resp_header/index.html index 769cd656..fdd8112d 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.has_resp_header/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.has_resp_header/index.html @@ -62,95 +62,46 @@

cowboy_req:has_resp_header(3)

-

Name

-
-

cowboy_req:has_resp_header - Is the given response header set?

-
-
-
+

cowboy_req:has_resp_header - Is the given response header set?

Description

-
-
-
-
has_resp_header(Name, Req :: cowboy_req:req()) -> boolean()
+
has_resp_header(Name, Req :: cowboy_req:req()) -> boolean()
 
-Name :: binary()  %% lowercase; case insensitive
-

Return whether the given response header has been set.

-

The header name must be given as a lowercase binary string. -While header names are case insensitive, Cowboy requires them -to be given as lowercase to function properly.

-
-
-
+Name :: binary() %% lowercase; case insensitive +
+

Return whether the given response header has been set.

+

The header name must be given as a lowercase binary string. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.

Arguments

-
-
-
-Name -
-
-

-Header name as a lowercase binary string. -

+
Name
+

Header name as a lowercase binary string.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

A boolean indicating whether the given response header has been set.

-
-
-
+

A boolean indicating whether the given response header has been set.

Changelog

-
-
    -
  • -

    -1.0: Function introduced. -

    +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Check whether the content-type header has been set
-
-
false = cowboy_req:has_resp_header(<<"content-type">>, Req0),
-Req = cowboy_req:set_resp_header(<<"content-type">>, <<"text/html">>, Req0),
-true = cowboy_req:has_resp_header(<<"content-type">>, Req).
-
-
-
+
false = cowboy_req:has_resp_header(<<"content-type">>, Req0),
+Req = cowboy_req:set_resp_header(<<"content-type">>, <<"text/html">>, Req0),
+true = cowboy_req:has_resp_header(<<"content-type">>, Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:set_resp_header(3), -cowboy_req:set_resp_headers(3), -cowboy_req:resp_header(3), -cowboy_req:resp_headers(3), -cowboy_req:delete_resp_header(3)

-
- +

cowboy_req(3), cowboy_req:set_resp_header(3), cowboy_req:set_resp_headers(3), cowboy_req:resp_header(3), cowboy_req:resp_headers(3), cowboy_req:delete_resp_header(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.header/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.header/index.html index 37651c85..b7c45c53 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.header/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.header/index.html @@ -62,122 +62,67 @@

cowboy_req:header(3)

-

Name

-
-

cowboy_req:header - HTTP header

-
-
-
+

cowboy_req:header - HTTP header

Description

-
-
-
-
header(Name, Req)          -> header(Name, Req, undefined)
-header(Name, Req, Default) -> binary() | Default
-
-Name    :: binary()          %% lowercase; case insensitive
-Req     :: cowboy_req:req()
-Default :: any()
-

Return the value for the given HTTP header.

-

The header name must be given as a lowercase binary string. -While header names are case insensitive, Cowboy requires them -to be given as lowercase to function properly.

-

Headers can also be obtained using pattern matching:

-
-
-
#{headers := #{Name := Value}} = Req.
-

Note that this snippet will crash if the header is missing.

-
-
-
+
#{headers := #{Name := Value}} = Req.
+
+

Note that this snippet will crash if the header is missing.

Arguments

-
-
-
-Name -
-
-

-Desired HTTP header name as a lowercase binary string. -

+
Name
+

Desired HTTP header name as a lowercase binary string.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-Default -
-
-

-Default value returned when the header is missing. -

+
Default
+

Default value returned when the header is missing.

-
-
- -
+

Return value

-
-

The header value is returned as a binary string. When the -header is missing, the default argument is returned.

-
-
-
+

The header value is returned as a binary string. When the header is missing, the default argument is returned.

Changelog

-
-
    -
  • -

    -2.0: Only the header value is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the header value is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the accept header
-
-
Accept = cowboy_req:header(<<"accept">>, Req).
-
-
Get the content-length header with a default value
-
-
Length = cowboy_req:header(<<"content-length">>, Req, <<"0">>).
-
-
-
+
Length = cowboy_req:header(<<"content-length">>, Req, <<"0">>).
+

See also

-
-

cowboy_req(3), -cowboy_req:headers(3), -cowboy_req:parse_header(3)

-
- +

cowboy_req(3), cowboy_req:headers(3), cowboy_req:parse_header(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.headers/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.headers/index.html index be20a74b..5b8af10f 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.headers/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.headers/index.html @@ -62,90 +62,47 @@

cowboy_req:headers(3)

-

Name

-
-

cowboy_req:headers - HTTP headers

-
-
-
+

cowboy_req:headers - HTTP headers

Description

-
-
-
-
headers(Req :: cowboy_req:req()) -> cowboy:http_headers()
-

Return all request headers.

-

Request headers can also be obtained using pattern matching:

-
-
-
#{headers := Headers} = Req.
-
-
-
+
#{headers := Headers} = Req.
+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

Headers are returned as a map with keys being lowercase -binary strings, and values as binary strings.

-
-
-
+

Headers are returned as a map with keys being lowercase binary strings, and values as binary strings.

Changelog

-
-
    -
  • -

    -2.0: Only the headers are returned, they are no longer wrapped in a tuple. -

    +
    • 2.0: Only the headers are returned, they are no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get all headers
-
-
Headers = cowboy_req:headers(Req).
-
-
-
+
Headers = cowboy_req:headers(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:header(3), -cowboy_req:parse_header(3)

-
- +

cowboy_req(3), cowboy_req:header(3), cowboy_req:parse_header(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.host/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.host/index.html index 11f1f6c2..25e40330 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.host/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.host/index.html @@ -62,91 +62,47 @@

cowboy_req:host(3)

-

Name

-
-

cowboy_req:host - URI host name

-
-
-
+

cowboy_req:host - URI host name

Description

-
-
-
-
host(Req :: cowboy_req:req()) -> Host :: binary()
-

Return the host name of the effective request URI.

-

The host name can also be obtained using pattern matching:

-
-
-
#{host := Host} = Req.
-
-
-
+
#{host := Host} = Req.
+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The host name is returned as a lowercase binary string. -It is case insensitive.

-
-
-
+

The host name is returned as a lowercase binary string. It is case insensitive.

Changelog

-
-
    -
  • -

    -2.0: Only the host name is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the host name is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the effective request URI’s host name
-
-
Host = cowboy_req:host(Req).
-
-
-
+
Host = cowboy_req:host(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:binding(3), -cowboy_req:bindings(3), -cowboy_req:host_info(3)

-
- +

cowboy_req(3), cowboy_req:binding(3), cowboy_req:bindings(3), cowboy_req:host_info(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.host_info/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.host_info/index.html index 17a45108..eb9336d0 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.host_info/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.host_info/index.html @@ -62,87 +62,41 @@

cowboy_req:host_info(3)

-

Name

-
-

cowboy_req:host_info - Access the route’s heading host segments

-
-
-
+

cowboy_req:host_info - Access the route's heading host segments

Description

-
-
-
-
host_info(Req :: cowboy_req:req()) -> cowboy_router:tokens()
-

Return the tokens for the heading host segments.

-

This is the part of the host name that was matched using -the ... notation.

-
-
-
+
host_info(Req :: cowboy_req:req()) -> cowboy_router:tokens()
+
+

Return the tokens for the heading host segments.

+

This is the part of the host name that was matched using the ... notation.

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The tokens are returned as a list of case insensitive -binary strings.

-
-
-
+

The tokens are returned as a list of case insensitive binary strings.

Changelog

-
-
    -
  • -

    -2.0: Only the tokens are returned, they are no longer wrapped in a tuple. -

    +
    • 2.0: Only the tokens are returned, they are no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the host_info tokens
-
-
HostInfo = cowboy_req:host_info(Req).
-
-
-
+
HostInfo = cowboy_req:host_info(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:binding(3), -cowboy_req:bindings(3), -cowboy_req:path_info(3), -cowboy_router(3)

-
- +

cowboy_req(3), cowboy_req:binding(3), cowboy_req:bindings(3), cowboy_req:path_info(3), cowboy_router(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.inform/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.inform/index.html index a94d8fe5..66a0f468 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.inform/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.inform/index.html @@ -62,125 +62,66 @@

cowboy_req:inform(3)

-

Name

-
-

cowboy_req:inform - Send an informational response

-
-
-
+

cowboy_req:inform - Send an informational response

Description

-
-
-
-
inform(Status, Req :: cowboy_req:req())
-    -> inform(StatusCode, #{}, Req)
-
-inform(Status, Headers, Req :: cowboy_req:req())
-    -> ok
-
-Status  :: cowboy:http_status()
-Headers :: cowboy:http_headers()
-

Send an informational response.

-

Informational responses use a status code between 100 and 199. -They cannot include a body. This function will not use any -of the previously set headers. All headers to be sent must -be given directly.

-

Any number of informational responses can be sent as long as -they are sent before the proper response. Attempting to use -this function after sending a normal response will result -in an error.

-

The header names must be given as lowercase binary strings. -While header names are case insensitive, Cowboy requires them -to be given as lowercase to function properly.

-
-
-
+
inform(Status, Req :: cowboy_req:req())
+    -> inform(StatusCode, #{}, Req)
+
+inform(Status, Headers, Req :: cowboy_req:req())
+    -> ok
+
+Status  :: cowboy:http_status()
+Headers :: cowboy:http_headers()
+
+

Send an informational response.

+

Informational responses use a status code between 100 and 199. They cannot include a body. This function will not use any of the previously set headers. All headers to be sent must be given directly.

+

Any number of informational responses can be sent as long as they are sent before the proper response. Attempting to use this function after sending a normal response will result in an error.

+

The header names must be given as lowercase binary strings. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.

Arguments

-
-
-
-Status -
-
-

-The status code for the response. -

+
Status
+

The status code for the response.

-
-Headers -
-
-

-The response headers. -

+
Headers
+

The response headers.

-
-

Header names must be given as lowercase binary strings.

-
-
-Req -
-
-

-The Req object. -

+
+

Header names must be given as lowercase binary strings.

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The atom ok is always returned. It can be safely ignored.

-
-
-
+

The atom ok is always returned. It can be safely ignored.

Changelog

-
-
    -
  • -

    -2.1: Function introduced. -

    +
    • 2.1: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Send an informational response
-
-
Req = cowboy_req:inform(102, Req0).
-
-
Send an informational response with headers
-
-
Req = cowboy_req:inform(103, #{
-    <<"link">> => <<"</style.css>; rel=preload; as=style">>,
-    <<"link">> => <<"</script.js>; rel=preload; as=script">>
-}, Req0).
-
-
-
+
Req = cowboy_req:inform(103, #{
+    <<"link">> => <<"</style.css>; rel=preload; as=style">>,
+    <<"link">> => <<"</script.js>; rel=preload; as=script">>
+}, Req0).
+

See also

-
-

cowboy_req(3), -cowboy_req:reply(3), -cowboy_req:stream_reply(3), -cowboy_req:push(3)

-
- +

cowboy_req(3), cowboy_req:reply(3), cowboy_req:stream_reply(3), cowboy_req:push(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.match_cookies/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.match_cookies/index.html index 251bd7e2..7403f023 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.match_cookies/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.match_cookies/index.html @@ -62,123 +62,67 @@

cowboy_req:match_cookies(3)

-

Name

-
-

cowboy_req:match_cookies - Match cookies against constraints

-
-
-
+

cowboy_req:match_cookies - Match cookies against constraints

Description

-
-
-
-
match_cookies(Fields :: cowboy:fields(), Req :: cowboy_req:req())
-    -> #{atom() => any()}
-

Parse the cookies and match specific values against -constraints.

-

Cowboy will only return the cookie values specified in the -fields list, and ignore all others. Fields can be either -the name of the cookie requested; the name along with a -list of constraints; or the name, a list of constraints -and a default value in case the cookie is missing.

-

This function will crash if the cookie is missing and no -default value is provided. This function will also crash -if a constraint fails.

-

The name of the cookie must be provided as an atom. The -key of the returned map will be that atom. The value may -be converted through the use of constraints, making this -function able to extract, validate and convert values all -in one step.

-
-
-
+
match_cookies(Fields :: cowboy:fields(), Req :: cowboy_req:req())
+    -> #{atom() => any()}
+
+

Parse the cookies and match specific values against constraints.

+

Cowboy will only return the cookie values specified in the fields list, and ignore all others. Fields can be either the name of the cookie requested; the name along with a list of constraints; or the name, a list of constraints and a default value in case the cookie is missing.

+

This function will crash if the cookie is missing and no default value is provided. This function will also crash if a constraint fails.

+

The name of the cookie must be provided as an atom. The key of the returned map will be that atom. The value may be converted through the use of constraints, making this function able to extract, validate and convert values all in one step.

Arguments

-
-
-
-Fields -
-
-

-Cookies to retrieve. -

-

See cowboy(3) for a complete description.

+
Fields
+

Cookies to retrieve.

+

See cowboy(3) for a complete description.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

Desired values are returned as a map. The key is the atom -that was given in the list of fields, and the value is the -optionally converted value after applying constraints.

-

The map contains the same keys that were given in the fields.

-

An exception is triggered when the match fails.

-
-
-
+

Desired values are returned as a map. The key is the atom that was given in the list of fields, and the value is the optionally converted value after applying constraints.

+

The map contains the same keys that were given in the fields.

+

An exception is triggered when the match fails.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. -

    +
    • 2.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Match fields
-
-
%% ID and Lang are binaries.
-#{id := ID, lang := Lang}
-    = cowboy_req:match_cookies([id, lang], Req).
-
-
Match fields and apply constraints
-
-
%% ID is an integer and Lang a non-empty binary.
-#{id := ID, lang := Lang}
-    = cowboy_req:match_cookies([{id, int}, {lang, nonempty}], Req).
-
-
Match fields with default values
-
-
#{lang := Lang}
-    = cowboy_req:match_cookies([{lang, [], <<"en-US">>}], Req).
-
-
-
+
#{lang := Lang}
+    = cowboy_req:match_cookies([{lang, [], <<"en-US">>}], Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:parse_cookies(3)

-
- +

cowboy_req(3), cowboy_req:parse_cookies(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.match_qs/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.match_qs/index.html index 14396da6..a5eaf848 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.match_qs/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.match_qs/index.html @@ -62,123 +62,67 @@

cowboy_req:match_qs(3)

-

Name

-
-

cowboy_req:match_qs - Match the query string against constraints

-
-
-
+

cowboy_req:match_qs - Match the query string against constraints

Description

-
-
-
-
match_qs(Fields :: cowboy:fields(), Req :: cowboy_req:req())
-    -> #{atom() => any()}
-

Parse the query string and match specific values against -constraints.

-

Cowboy will only return the query string values specified -in the fields list, and ignore all others. Fields can be -either the key requested; the key along with a list of -constraints; or the key, a list of constraints and a -default value in case the key is missing.

-

This function will crash if the key is missing and no -default value is provided. This function will also crash -if a constraint fails.

-

The key must be provided as an atom. The key of the -returned map will be that atom. The value may be converted -through the use of constraints, making this function able -to extract, validate and convert values all in one step.

-
-
-
+
match_qs(Fields :: cowboy:fields(), Req :: cowboy_req:req())
+    -> #{atom() => any()}
+
+

Parse the query string and match specific values against constraints.

+

Cowboy will only return the query string values specified in the fields list, and ignore all others. Fields can be either the key requested; the key along with a list of constraints; or the key, a list of constraints and a default value in case the key is missing.

+

This function will crash if the key is missing and no default value is provided. This function will also crash if a constraint fails.

+

The key must be provided as an atom. The key of the returned map will be that atom. The value may be converted through the use of constraints, making this function able to extract, validate and convert values all in one step.

Arguments

-
-
-
-Fields -
-
-

-Fields to retrieve from the query string. -

-

See cowboy(3) for a complete description.

+
Fields
+

Fields to retrieve from the query string.

+

See cowboy(3) for a complete description.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

Desired values are returned as a map. The key is the atom -that was given in the list of fields, and the value is the -optionally converted value after applying constraints.

-

The map contains the same keys that were given in the fields.

-

An exception is triggered when the match fails.

-
-
-
+

Desired values are returned as a map. The key is the atom that was given in the list of fields, and the value is the optionally converted value after applying constraints.

+

The map contains the same keys that were given in the fields.

+

An exception is triggered when the match fails.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. -

    +
    • 2.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Match fields
-
-
%% ID and Lang are binaries.
-#{id := ID, lang := Lang}
-    = cowboy_req:match_qs([id, lang], Req).
-
-
Match fields and apply constraints
-
-
%% ID is an integer and Lang a non-empty binary.
-#{id := ID, lang := Lang}
-    = cowboy_req:match_qs([{id, int}, {lang, nonempty}], Req).
-
-
Match fields with default values
-
-
#{lang := Lang}
-    = cowboy_req:match_qs([{lang, [], <<"en-US">>}], Req).
-
-
-
+
#{lang := Lang}
+    = cowboy_req:match_qs([{lang, [], <<"en-US">>}], Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:qs(3), -cowboy_req:parse_qs(3)

-
- +

cowboy_req(3), cowboy_req:qs(3), cowboy_req:parse_qs(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.method/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.method/index.html index 38140e1f..514abc5e 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.method/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.method/index.html @@ -62,100 +62,58 @@

cowboy_req:method(3)

-

Name

-
-

cowboy_req:method - HTTP method

-
-
-
+

cowboy_req:method - HTTP method

Description

-
-
-
-
method(Req :: cowboy_req:req()) -> Method :: binary()
-

Return the request’s HTTP method.

-

The method can also be obtained using pattern matching:

-
-
-
#{method := Method} = Req.
-
-
-
+
#{method := Method} = Req.
+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The request’s HTTP method is returned as a binary string. -While methods are case sensitive, standard methods are -always uppercase.

-
-
-
+

The request's HTTP method is returned as a binary string. While methods are case sensitive, standard methods are always uppercase.

Changelog

-
-
    -
  • -

    -2.0: Only the method is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the method is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Ensure the request’s method is GET
-
-
<<"GET">> = cowboy_req:method(Req).
-
-
Allow methods from list
-
-
init(Req, State) ->
-    case lists:member(cowboy_req:method(Req), [<<"GET">>, <<"POST">>]) of
-        true -> handle(Req, State);
-        false -> method_not_allowed(Req, State)
-    end.
-
-
-
+
init(Req, State) ->
+    case lists:member(cowboy_req:method(Req), [<<"GET">>, <<"POST">>]) of
+        true -> handle(Req, State);
+        false -> method_not_allowed(Req, State)
+    end.
+

See also

-
-

cowboy_req(3)

-
- +

cowboy_req(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.parse_cookies/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.parse_cookies/index.html index 813c331f..855d20ad 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.parse_cookies/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.parse_cookies/index.html @@ -62,91 +62,47 @@

cowboy_req:parse_cookies(3)

-

Name

-
-

cowboy_req:parse_cookies - Parse cookie headers

-
-
-
+

cowboy_req:parse_cookies - Parse cookie headers

Description

-
-
-
-
parse_cookies(Req) -> [{Name, Value}]
-
-Name  :: binary() %% case sensitive
-Value :: binary() %% case sensitive
-

Parse cookie headers.

-

Alias for cowboy_req:parse_header([cookie], Req).

-

When the cookie header is missing, [] is returned.

-

While an empty cookie header is not valid, some clients do -send it. Cowboy will in this case also return [].

-
-
-
+
parse_cookies(Req) -> [{Name, Value}]
+
+Name  :: binary() %% case sensitive
+Value :: binary() %% case sensitive
+
+

Parse cookie headers.

+

Alias for cowboy_req:parse_header(<<"cookie">>, Req).

+

When the cookie header is missing, [] is returned.

+

While an empty cookie header is not valid, some clients do send it. Cowboy will in this case also return [].

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The cookies are returned as a list of key/values. Keys and -values are case sensitive binary strings.

-
-
-
+

The cookies are returned as a list of key/values. Keys and values are case sensitive binary strings.

Changelog

-
-
    -
  • -

    -2.0: Only the parsed header value is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the parsed header value is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -2.0: Function introduced. Replaces cookie/2,3 and cookies/1. -

      +
    • 2.0: Function introduced. Replaces cookie/2,3 and cookies/1.
      • -
-
-
-
+

Examples

-
-
-
Look for a specific cookie
-
-
Cookies = cowboy_req:parse_cookies(Req),
-{_, Token} = lists:keyfind(<<"token">>, 1, Cookies).
-
-
-
+
Cookies = cowboy_req:parse_cookies(Req),
+{_, Token} = lists:keyfind(<<"token">>, 1, Cookies).
+

See also

-
-

cowboy_req(3), -cowboy_req:parse_header(3), -cowboy_req:match_cookies(3)

-
- +

cowboy_req(3), cowboy_req:parse_header(3), cowboy_req:match_cookies(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.parse_header/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.parse_header/index.html index c199e91b..93cff336 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.parse_header/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.parse_header/index.html @@ -62,283 +62,218 @@

cowboy_req:parse_header(3)

-

Name

-
-

cowboy_req:parse_header - Parse the given HTTP header

-
-
-
+

cowboy_req:parse_header - Parse the given HTTP header

Description

-
-
-
-
parse_header(Name, Req)          -> ParsedValue | Default
-parse_header(Name, Req, Default) -> ParsedValue | Default
-
-Name        :: binary()
-Req         :: cowboy_req:req()
-ParsedValue :: any()
-Default     :: any()
-

Parse the given HTTP header.

-

The header name must be given as a lowercase binary string. -While header names are case insensitive, Cowboy requires them -to be given as lowercase to function properly.

-

The type of the parsed value varies depending on -the header. Similarly, the default value when calling -cowboy_req:parse_header/2 differs depending on the -header.

-
-
-
+
parse_header(Name, Req)          -> ParsedValue | Default
+parse_header(Name, Req, Default) -> ParsedValue | Default
+
+Name        :: binary()
+Req         :: cowboy_req:req()
+ParsedValue :: any()
+Default     :: any()
+
+

Parse the given HTTP header.

+

The header name must be given as a lowercase binary string. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.

+

The type of the parsed value varies depending on the header. Similarly, the default value when calling cowboy_req:parse_header/2 differs depending on the header.

Arguments

-
-
-
-Name -
-
-

-Desired HTTP header name as a lowercase binary string. -

+
Name
+

Desired HTTP header name as a lowercase binary string.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-Default -
-
-

-Default value returned when the header is missing. -

+
Default
+

Default value returned when the header is missing.

-
-
- -
+

Return value

-
-

The parsed header value varies depending on the header. -When the header is missing, the default argument is returned.

-
-
-
+

The parsed header value varies depending on the header. When the header is missing, the default argument is returned.

Headers

-
-

The following snippets detail the types returned by the -different headers. Unless mentioned otherwise, the -default value when the header is missing will be undefined:

-
-
accept
-
-
parse_header(<<"accept">>, Req)
-    -> [{{Type, SubType, Params}, Quality, AcceptExt}]
-
-Type      :: binary()               %% case insensitive
-SubType   :: binary()               %% case insensitive
-Params    :: [{Key, Value}]
-Quality   :: 0..1000
-AcceptExt :: [Key | {Key, Value}]
-Key       :: binary()               %% case insensitive
-Value     :: binary()               %% case sensitive
-
-
accept-charset, accept-encoding and accept-language
-
-
parse_header(Name, Req) -> [{Value, Quality}]
-
-Name    :: <<"accept-charset">>
-         | <<"accept-encoding">>
-         | <<"accept-language">>
-Value   :: binary()                 %% case insensitive
-Quality :: 0..1000
-
-
authorization
-
-
parse_header(<<"authorization">>, Req)
-    -> {basic, Username :: binary(), Password :: binary()}
-     | {bearer, Token :: binary()}
-     | {digest, [{Key :: binary(), Value :: binary()}]}
-
-
content-length
-
+
content-length
+
-
parse_header(<<"content-length">>, Req) -> non_neg_integer()
-

When the content-length header is missing, 0 is returned.

-
-
content-type
-
-
parse_header(<<"content-type">>, Req)
-    -> {Type, SubType, Params}
-
-Type      :: binary()               %% case insensitive
-SubType   :: binary()               %% case insensitive
-Params    :: [{Key, Value}]
-Key       :: binary()               %% case insensitive
-Value     :: binary()               %% case sensitive;
-

Note that the value for the charset parameter is case insensitive -and returned as a lowercase binary string.

-
-
cookie
-
-
parse_header(<<"cookie">>, Req) -> [{Name, Value}]
-
-Name  :: binary()                   %% case sensitive
-Value :: binary()                   %% case sensitive
-

When the cookie header is missing, [] is returned.

-

While an empty cookie header is not valid, some clients do -send it. Cowboy will in this case also return [].

-
-
expect
-
-
parse_header(<<"expect">>, Req) -> continue
-
-
if-match and if-none-match
-
-
parse_header(Name, Req)
-    -> '*' | [{weak | strong, OpaqueTag}]
-
-Name      :: <<"if-match">>
-           | <<"if-none-match">>
-OpaqueTag :: binary()               %% case sensitive
-
-
if-modified-since and if-unmodified-since
-
-
parse_header(Name, Req) -> calendar:datetime()
-
-
range
-
-
parse_header(<<"range">>, Req) -> {From, To} | Final
-
-From  :: non_neg_integer()
-To    :: non_neg_integer() | infinity
-Final :: neg_integer()
-
-
sec-websocket-extensions
-
-
parse_header(<<"sec-websocket-extensions">>, Req)
-    -> [{Extension, Params}]
-
-Extension :: binary()               %% case sensitive
-Params    :: [Key | {Key, Value}]
-Key       :: binary()               %% case sensitive
-Value     :: binary()               %% case sensitive
-
-
sec-websocket-protocol and upgrade
-
-
parse_header(Name, Req) -> [Token]
-
-Name  :: <<"sec-websocket-protocol">>
-       | <<"upgrade">>
-Token :: binary()                   %% case insensitive
-
-
x-forwarded-for
-
-
parse_header(<<"x-forwarded-for">>, Req) -> [Token]
+
parse_header(<<"x-forwarded-for">>, Req) -> [Token]
 
-Token :: binary()                   %% case sensitive
-
-
Unknown headers
-
-
parse_header(_, Req) -> {undefined, RawValue}
-
-
-
+
parse_header(_, Req) -> {undefined, RawValue}
+

Changelog

-
-
    -
  • -

    -2.0: Only the parsed header value is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the parsed header value is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Parse the accept header with a custom default value
-
-
%% Accept everything when header is missing.
-Accept = cowboy_req:parse_header(<<"accept">>, Req,
-    [{{ <<"*">>, <<"*">>, []}, 1000, []}]).
-
-
Parse the content-length header
-
-
%% Default content-length is 0.
-Length = cowboy_req:header(<<"content-length">>, Req).
-
-
-
+
%% Default content-length is 0.
+Length = cowboy_req:header(<<"content-length">>, Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:header(3), -cowboy_req:headers(3)

-
- +

cowboy_req(3), cowboy_req:header(3), cowboy_req:headers(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.parse_qs/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.parse_qs/index.html index 9894f0de..69f99f1b 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.parse_qs/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.parse_qs/index.html @@ -62,117 +62,55 @@

cowboy_req:parse_qs(3)

-

Name

-
-

cowboy_req:parse_qs - Parse the query string

-
-
-
+

cowboy_req:parse_qs - Parse the query string

Description

-
-
-
-
parse_qs(Req :: cowboy_req:req())
-    -> [{Key :: binary(), Value :: binary() | true}]
-

Parse the query string as a list of key/value pairs.

-
-
-
+
parse_qs(Req :: cowboy_req:req())
+    -> [{Key :: binary(), Value :: binary() | true}]
+
+

Parse the query string as a list of key/value pairs.

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The parsed query string is returned as a list of key/value pairs. -The key is a binary string. The value is either a binary string, -or the atom true. Both key and value are case sensitive.

-

The atom true is returned when a key is present in the query -string without a value. For example, in the following URIs -the key <<"edit">> will always have the value true:

-
    -
  • -

    -/posts/42?edit -

    +

    The parsed query string is returned as a list of key/value pairs. The key is a binary string. The value is either a binary string, or the atom true. Both key and value are case sensitive.

    +

    The atom true is returned when a key is present in the query string without a value. For example, in the following URIs the key <<"edit">> will always have the value true:

    +
    • /posts/42?edit
      • -
    • -

      -/posts/42?edit&exclusive=1 -

      +
    • /posts/42?edit&exclusive=1
      • -
    • -

      -/posts/42?exclusive=1&edit -

      +
    • /posts/42?exclusive=1&edit
      • -
    • -

      -/posts/42?exclusive=1&edit&from=web -

      +
    • /posts/42?exclusive=1&edit&from=web
      • -
-
-
-
+

Changelog

-
-
    -
  • -

    -2.0: The parsed value is not longer cached in the Req object. -

    +
    • 2.0: The parsed value is not longer cached in the Req object.
      • -
    • -

      -2.0: Only the parsed query string is returned, it is no longer wrapped in a tuple. -

      +
    • 2.0: Only the parsed query string is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -2.0: Function introduced. Replaces qs_val/1 and qs_vals/1. -

      +
    • 2.0: Function introduced. Replaces qs_val/1 and qs_vals/1.
      • -
-
-
-
+

Examples

-
-
-
Parse the query string and convert the keys to atoms
-
-
ParsedQs = cowboy_req:parse_qs(Req),
-AtomsQs = [{binary_to_existing_atom(K, latin1), V}
-    || {K, V} <- ParsedQs].
-
-
-
+
ParsedQs = cowboy_req:parse_qs(Req),
+AtomsQs = [{binary_to_existing_atom(K, latin1), V}
+    || {K, V} <- ParsedQs].
+

See also

-
-

cowboy_req(3), -cowboy_req:qs(3), -cowboy_req:match_qs(3)

-
- +

cowboy_req(3), cowboy_req:qs(3), cowboy_req:match_qs(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.path/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.path/index.html index bc55a705..9432bc45 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.path/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.path/index.html @@ -62,90 +62,47 @@

cowboy_req:path(3)

-

Name

-
-

cowboy_req:path - URI path

-
-
-
+

cowboy_req:path - URI path

Description

-
-
-
-
path(Req :: cowboy_req:req()) -> Path :: binary()
-

Return the path of the effective request URI.

-

The path can also be obtained using pattern matching:

-
-
-
#{path := Path} = Req.
-
-
-
+
#{path := Path} = Req.
+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The path is returned as a binary string. It is case sensitive.

-
-
-
+

The path is returned as a binary string. It is case sensitive.

Changelog

-
-
    -
  • -

    -2.0: Only the path is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the path is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the effective request URI’s path
-
-
Path = cowboy_req:path(Req).
-
-
-
+
Path = cowboy_req:path(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:binding(3), -cowboy_req:bindings(3), -cowboy_req:path_info(3)

-
- +

cowboy_req(3), cowboy_req:binding(3), cowboy_req:bindings(3), cowboy_req:path_info(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.path_info/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.path_info/index.html index 328ae0c5..e03ef029 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.path_info/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.path_info/index.html @@ -62,87 +62,41 @@

cowboy_req:path_info(3)

-

Name

-
-

cowboy_req:path_info - Access the route’s trailing path segments

-
-
-
+

cowboy_req:path_info - Access the route's trailing path segments

Description

-
-
-
-
path_info(Req :: cowboy_req:req()) -> cowboy_router:tokens()
-

Return the tokens for the trailing path segments.

-

This is the part of the host name that was matched using -the ... notation.

-
-
-
+
path_info(Req :: cowboy_req:req()) -> cowboy_router:tokens()
+
+

Return the tokens for the trailing path segments.

+

This is the part of the host name that was matched using the ... notation.

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The tokens are returned as a list of case sensitive -binary strings.

-
-
-
+

The tokens are returned as a list of case sensitive binary strings.

Changelog

-
-
    -
  • -

    -2.0: Only the tokens are returned, they are no longer wrapped in a tuple. -

    +
    • 2.0: Only the tokens are returned, they are no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the path_info tokens
-
-
PathInfo = cowboy_req:path_info(Req).
-
-
-
+
PathInfo = cowboy_req:path_info(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:binding(3), -cowboy_req:bindings(3), -cowboy_req:host_info(3), -cowboy_router(3)

-
- +

cowboy_req(3), cowboy_req:binding(3), cowboy_req:bindings(3), cowboy_req:host_info(3), cowboy_router(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.peer/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.peer/index.html index 46d2262b..f9ec4efb 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.peer/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.peer/index.html @@ -62,98 +62,51 @@

cowboy_req:peer(3)

-

Name

-
-

cowboy_req:peer - Peer address and port

-
-
-
+

cowboy_req:peer - Peer address and port

Description

-
-
-
-
peer(Req :: cowboy_req:req()) -> Info
+
peer(Req :: cowboy_req:req()) -> Info
 
-Info :: {inet:ip_address(), inet:port_number()}
-

Return the peer’s IP address and port number.

-

The peer information can also be obtained using pattern matching:

-
-
-
#{peer := {IP, Port}} = Req.
-
-
-
+
#{peer := {IP, Port}} = Req.
+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The peer’s IP address and port number.

-

The peer is not necessarily the client’s IP address and port. -It is the IP address of the endpoint connecting directly to -the server, which may be a gateway or a proxy.

-

The forwarded header can be used to get better information -about the different endpoints from the client to the server. -Note however that it is only informative; there is no reliable -way of determining the source of an HTTP request.

-
-
-
+

The peer's IP address and port number.

+

The peer is not necessarily the client's IP address and port. It is the IP address of the endpoint connecting directly to the server, which may be a gateway or a proxy.

+

The forwarded header can be used to get better information about the different endpoints from the client to the server. Note however that it is only informative; there is no reliable way of determining the source of an HTTP request.

Changelog

-
-
    -
  • -

    -2.0: Only the peer is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the peer is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the peer IP address and port number.
-
-
{IP, Port} = cowboy_req:peer(Req).
-
-
-
+
{IP, Port} = cowboy_req:peer(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:sock(3), -cowboy_req:cert(3)

-
- +

cowboy_req(3), cowboy_req:sock(3), cowboy_req:cert(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.port/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.port/index.html index 4d9e6fc7..4e32535c 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.port/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.port/index.html @@ -62,90 +62,48 @@

cowboy_req:port(3)

-

Name

-
-

cowboy_req:port - URI port number

-
-
-
+

cowboy_req:port - URI port number

Description

-
-
-
-
port(Req :: cowboy_req:req()) -> Port :: inet:port_number()
-

Return the port number of the effective request URI.

-

Note that the port number returned by this function is obtained -by parsing the host header. It may be different from the port -the peer used to connect to Cowboy.

-

The port number can also be obtained using pattern matching:

-
-
-
#{port := Port} = Req.
-
-
-
+
#{port := Port} = Req.
+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The port number is returned as an integer.

-
-
-
+

The port number is returned as an integer.

Changelog

-
-
    -
  • -

    -2.0: Only the port number is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the port number is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the effective request URI’s port number
-
-
Port = cowboy_req:port(Req).
-
-
-
+
Port = cowboy_req:port(Req).
+

See also

-
-

cowboy_req(3)

-
- +

cowboy_req(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.push/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.push/index.html index ac272086..e1238d72 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.push/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.push/index.html @@ -62,142 +62,74 @@

cowboy_req:push(3)

-

Name

-
-

cowboy_req:push - Push a resource to the client

-
-
-
+

cowboy_req:push - Push a resource to the client

Description

-
-
-
-
push(Path, Headers, Req :: cowboy_req:req())
-    -> push(Path, Headers, Req, #{})
-
-push(Path, Headers, Req :: cowboy_req:req(), Opts)
-    -> ok
-
-Path    :: iodata()                %% case sensitive
-Headers :: cowboy:http_headers()
-Opts    :: cowboy_req:push_opts()
-

Push a resource to the client.

-

Cowboy handles push requests the same way as if they came -from the client, including the creation of a request handling -process, routing and middlewares and so on.

-

This function does nothing when the HTTP/1.1 protocol is -used. You may call it safely without first checking whether -the connection uses HTTP/2.

-

The header names must be given as lowercase binary strings. -While header names are case insensitive, Cowboy requires them -to be given as lowercase to function properly.

-

Note that the headers must be the headers the client is expected -to send if it were to perform the request. They are therefore -request headers, and not response headers.

-

By default, Cowboy will use the GET method, an empty query string, -and take the scheme, host and port directly from the current -request’s URI. You can override them by passing options.

-

It is not possible to push resources after sending a response. -Any attempt will result in an error.

-
-
-
+
push(Path, Headers, Req :: cowboy_req:req())
+    -> push(Path, Headers, Req, #{})
+
+push(Path, Headers, Req :: cowboy_req:req(), Opts)
+    -> ok
+
+Path    :: iodata()                %% case sensitive
+Headers :: cowboy:http_headers()
+Opts    :: cowboy_req:push_opts()
+
+

Push a resource to the client.

+

Cowboy handles push requests the same way as if they came from the client, including the creation of a request handling process, routing and middlewares and so on.

+

This function does nothing when the HTTP/1.1 protocol is used. You may call it safely without first checking whether the connection uses HTTP/2.

+

The header names must be given as lowercase binary strings. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.

+

Note that the headers must be the headers the client is expected to send if it were to perform the request. They are therefore request headers, and not response headers.

+

By default, Cowboy will use the GET method, an empty query string, and take the scheme, host and port directly from the current request's URI. You can override them by passing options.

+

It is not possible to push resources after sending a response. Any attempt will result in an error.

Arguments

-
-
-
-Path -
-
-

-The status code for the response. -

+
Path
+

The status code for the response.

-
-Headers -
-
-

-The response headers. -

+
Headers
+

The response headers.

-
-

Header names must be given as lowercase binary strings.

-
-
-Req -
-
-

-The Req object. -

+
+

Header names must be given as lowercase binary strings.

+
Req
+

The Req object.

-
-Opts -
-
-

-Customize the HTTP method or the URI scheme, host, port -or query string. -

+
Opts
+

Customize the HTTP method or the URI scheme, host, port or query string.

-
-
- -
+

Return value

-
-

The atom ok is always returned. It can be safely ignored.

-
-
-
+

The atom ok is always returned. It can be safely ignored.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. -

    +
    • 2.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Push a resource
-
-
cowboy_req:push("/static/style.css", #{
-    <<"accept">> => <<"text/css">>
-}, Req),
-
-
Push a resource with a custom host
-
-
cowboy_req:push("/static/style.css", #{
-    <<"accept">> => <<"text/css">>
-}, #{host => <<"cdn.example.org">>}, Req),
-
-
-
+
cowboy_req:push("/static/style.css", #{
+    <<"accept">> => <<"text/css">>
+}, #{host => <<"cdn.example.org">>}, Req),
+

See also

-
-

cowboy_req(3), -cowboy_req:inform(3), -cowboy_req:reply(3), -cowboy_req:stream_reply(3)

-
- +

cowboy_req(3), cowboy_req:inform(3), cowboy_req:reply(3), cowboy_req:stream_reply(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.qs/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.qs/index.html index 352719b5..482047e2 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.qs/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.qs/index.html @@ -62,89 +62,47 @@

cowboy_req:qs(3)

-

Name

-
-

cowboy_req:qs - URI query string

-
-
-
+

cowboy_req:qs - URI query string

Description

-
-
-
-
qs(Req :: cowboy_req:req()) -> Qs :: binary()
-

Return the query string of the effective request URI.

-

The query string can also be obtained using pattern matching:

-
-
-
#{qs := Qs} = Req.
-
-
-
+
#{qs := Qs} = Req.
+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The query string is returned as a binary string. It is case sensitive.

-
-
-
+

The query string is returned as a binary string. It is case sensitive.

Changelog

-
-
    -
  • -

    -2.0: Only the query string is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the query string is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the effective request URI’s query string
-
-
Qs = cowboy_req:qs(Req).
-
-
-
+
Qs = cowboy_req:qs(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:parse_qs(3), -cowboy_req:match_qs(3)

-
- +

cowboy_req(3), cowboy_req:parse_qs(3), cowboy_req:match_qs(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.read_body/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.read_body/index.html index deceb1ec..d74da7da 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.read_body/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.read_body/index.html @@ -62,143 +62,72 @@

cowboy_req:read_body(3)

-

Name

-
-

cowboy_req:read_body - Read the request body

-
-
-
+

cowboy_req:read_body - Read the request body

Description

-
-
-
-
read_body(Req :: cowboy_req:req())
-    -> read_body(Req, #{})
-
-read_body(Req :: cowboy_req:req(), Opts)
-    -> {ok,   Data :: binary(), Req}
-     | {more, Data :: binary(), Req}
-
-Opts :: cowboy_req:read_body_opts()
-

Read the request body.

-

This function reads a chunk of the request body. A more tuple -is returned when more data remains to be read. Call the function -repeatedly until an ok tuple is returned to read the entire body.

-

An ok tuple with empty data is returned when the request has no body, -or when calling this function again after the body has already -been read. It is therefore safe to call this function directly. -Note that the body can only be read once.

-

This function reads the request body from the connection process. -The connection process is responsible for reading from the socket. -The exact behavior varies depending on the protocol.

-

The options therefore are only related to the communication -between the request process and the connection process.

-

Cowboy will automatically handle protocol details including -the expect header, chunked transfer-encoding and others.

-

Once the body has been read fully, Cowboy sets the content-length -header if it was not previously provided.

-
-
-
+
read_body(Req :: cowboy_req:req())
+    -> read_body(Req, #{})
+
+read_body(Req :: cowboy_req:req(), Opts)
+    -> {ok,   Data :: binary(), Req}
+     | {more, Data :: binary(), Req}
+
+Opts :: cowboy_req:read_body_opts()
+
+

Read the request body.

+

This function reads a chunk of the request body. A more tuple is returned when more data remains to be read. Call the function repeatedly until an ok tuple is returned to read the entire body.

+

An ok tuple with empty data is returned when the request has no body, or when calling this function again after the body has already been read. It is therefore safe to call this function directly. Note that the body can only be read once.

+

This function reads the request body from the connection process. The connection process is responsible for reading from the socket. The exact behavior varies depending on the protocol.

+

The options therefore are only related to the communication between the request process and the connection process.

+

Cowboy will automatically handle protocol details including the expect header, chunked transfer-encoding and others.

+

Once the body has been read fully, Cowboy sets the content-length header if it was not previously provided.

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-Opts -
-
-

-A map of body reading options. -

-

The length option can be used to request smaller or bigger -chunks of data to be sent. It is a best effort approach, Cowboy -may send more data than configured on occasions. It defaults -to 8MB.

-

The period indicates how long the connection process will wait -before it provides us with the data it received. It defaults -to 15 seconds.

-

The connection process sends data to the request process when -either the length of data or the period of time is reached.

-

The timeout option is a safeguard in case the connection -process becomes unresponsive. The function will crash if no -message was received in that interval. The timeout should be -larger than the period. It defaults to the period + 1 second.

+
Opts
+

A map of body reading options.

+

The length option can be used to request smaller or bigger chunks of data to be sent. It is a best effort approach, Cowboy may send more data than configured on occasions. It defaults to 8MB.

+

The period indicates how long the connection process will wait before it provides us with the data it received. It defaults to 15 seconds.

+

The connection process sends data to the request process when either the length of data or the period of time is reached.

+

The timeout option is a safeguard in case the connection process becomes unresponsive. The function will crash if no message was received in that interval. The timeout should be larger than the period. It defaults to the period
1 second.

-
-
- -
+

Return value

-
-

A more tuple is returned when there are more data to be read.

-

An ok tuple is returned when there are no more data to be read, -either because this is the last chunk of data, the body has already -been read, or there was no body to begin with.

-

The data is always returned as a binary.

-

The Req object returned in the tuple must be used for that point -onward. It contains a more up to date representation of the request. -For example it may have an added content-length header once the -body has been read.

-
-
-
+

A more tuple is returned when there are more data to be read.

+

An ok tuple is returned when there are no more data to be read, either because this is the last chunk of data, the body has already been read, or there was no body to begin with.

+

The data is always returned as a binary.

+

The Req object returned in the tuple must be used for that point onward. It contains a more up to date representation of the request. For example it may have an added content-length header once the body has been read.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. Replaces body/1,2. -

    +
    • 2.0: Function introduced. Replaces body/1,2.
      • -
-
-
-
+

Examples

-
-
-
Read the entire body
-
-
read_body(Req0, Acc) ->
-    case cowboy_req:read_body(Req0) of
-        {ok, Data, Req} -> {ok, << Acc/binary, Data/binary >>, Req};
-        {more, Data, Req} -> read_body(Req, << Acc/binary, Data/binary >>)
-    end.
-
-
Read the body in small chunks
-
-
cowboy_req:read_body(Req, #{length => 64000}).
-
-
-
+
cowboy_req:read_body(Req, #{length => 64000}).
+

See also

-
-

cowboy_req(3), -cowboy_req:has_body(3), -cowboy_req:body_length(3), -cowboy_req:read_urlencoded_body(3), -cowboy_req:read_part(3), -cowboy_req:read_part_body(3)

-
- +

cowboy_req(3), cowboy_req:has_body(3), cowboy_req:body_length(3), cowboy_req:read_urlencoded_body(3), cowboy_req:read_part(3), cowboy_req:read_part_body(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.read_part/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.read_part/index.html index 4a9fa13d..0fa219b0 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.read_part/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.read_part/index.html @@ -62,162 +62,94 @@

cowboy_req:read_part(3)

-

Name

-
-

cowboy_req:read_part - Read the next multipart headers

-
-
-
+

cowboy_req:read_part - Read the next multipart headers

Description

-
-
-
-
read_part(Req :: cowboy_req:req())
-    -> read_part(Req, #{})
-
-read_part(Req :: cowboy_req:req(), Opts)
-    -> {ok, Headers, Req} | {done, Req}
-
-Opts    :: cowboy_req:read_body_opts()
-Headers :: #{binary() => binary()}
-

Read the next part of a multipart body.

-

This function reads the request body and parses it as -multipart. Each parts of a multipart representation have -their own headers and body. This function parses and returns -headers. Examples of multipart media types are -multipart/form-data and multipart/byteranges.

-

Cowboy will skip any data remaining until the beginning of -the next part. This includes the preamble to the multipart -message but also the body of a previous part if it hasn’t -been read. Both are skipped automatically when calling this -function.

-

Cowboy will read the body before parsing in chunks of size -up to 64KB, with a period of 5 seconds. This is tailored for -reading part headers and might not be the most efficient for -skipping the previous part’s body.

-

The headers returned are MIME headers, NOT HTTP headers. -They can be parsed using the functions from the cow_multipart -module. In addition, the cow_multipart:form_data/1 function -can be used to quickly extract information from multipart/form-data -representations.

-

Once a part has been read, it can not be read again.

-

Once the body has been read, Cowboy sets the content-length -header if it was not previously provided.

-
-
-
+
read_part(Req :: cowboy_req:req())
+    -> read_part(Req, #{})
+
+read_part(Req :: cowboy_req:req(), Opts)
+    -> {ok, Headers, Req} | {done, Req}
+
+Opts    :: cowboy_req:read_body_opts()
+Headers :: #{binary() => binary()}
+
+

Read the next part of a multipart body.

+

This function reads the request body and parses it as multipart. Each parts of a multipart representation have their own headers and body. This function parses and returns headers. Examples of multipart media types are multipart/form-data and multipart/byteranges.

+

Cowboy will skip any data remaining until the beginning of the next part. This includes the preamble to the multipart message but also the body of a previous part if it hasn't been read. Both are skipped automatically when calling this function.

+

Cowboy will read the body before parsing in chunks of size up to 64KB, with a period of 5 seconds. This is tailored for reading part headers and might not be the most efficient for skipping the previous part's body.

+

The headers returned are MIME headers, NOT HTTP headers. They can be parsed using the functions from the cow_multipart module. In addition, the cow_multipart:form_data/1 function can be used to quickly extract information from multipart/form-data representations.

+ +

Once a part has been read, it can not be read again.

+

Once the body has been read, Cowboy sets the content-length header if it was not previously provided.

+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-Opts -
-
-

-A map of body reading options. Please refer to -cowboy_req:read_body(3) -for details about each option. -

-

This function defaults the length to 64KB and the period -to 5 seconds.

+
Opts
+

A map of body reading options. Please refer to cowboy_req:read_body(3) for details about each option.

+

This function defaults the length to 64KB and the period to 5 seconds.

-
-
- -
+

Return value

-
-

An ok tuple is returned containing the next part’s headers -as a map.

-

A done tuple is returned if there are no more parts to read.

-

The Req object returned in the tuple must be used for that point -onward. It contains a more up to date representation of the request. -For example it may have an added content-length header once the -body has been read.

-
-
-
+

An ok tuple is returned containing the next part's headers as a map.

+

A done tuple is returned if there are no more parts to read.

+

The Req object returned in the tuple must be used for that point onward. It contains a more up to date representation of the request. For example it may have an added content-length header once the body has been read.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. Replaces part/1,2. -

    +
    • 2.0: Function introduced. Replaces part/1,2.
      • -
-
-
-
+

Examples

-
-
-
Read all parts
-
-
acc_multipart(Req0, Acc) ->
-    case cowboy_req:read_part(Req0) of
-        {ok, Headers, Req1} ->
-            {ok, Body, Req} = stream_body(Req1, <<>>),
-            acc_multipart(Req, [{Headers, Body}|Acc]);
-        {done, Req} ->
-            {lists:reverse(Acc), Req}
-    end.
-
-stream_body(Req0, Acc) ->
-    case cowboy_req:read_part_body(Req0) of
-        {more, Data, Req} ->
-            stream_body(Req, << Acc/binary, Data/binary >>);
-        {ok, Data, Req} ->
-            {ok, << Acc/binary, Data/binary >>, Req}
-    end.
-
-
Read all part headers, skipping bodies
-
-
skip_body_multipart(Req0, Acc) ->
-    case cowboy_req:read_part(Req0) of
-        {ok, Headers, Req} ->
-            skip_body_multipart(Req, [Headers|Acc]);
-        {done, Req} ->
-            {lists:reverse(Acc), Req}
-    end.
-
-
Read a part header in larger chunks
-
-
{ok, Headers, Req} = cowboy_req:read_part(Req0, #{length => 1000000}).
-
-
-
+
{ok, Headers, Req} = cowboy_req:read_part(Req0, #{length => 1000000}).
+

See also

-
-

cowboy_req(3), -cowboy_req:has_body(3), -cowboy_req:body_length(3), -cowboy_req:read_body(3), -cowboy_req:read_urlencoded_body(3), -cowboy_req:read_part_body(3)

-
- +

cowboy_req(3), cowboy_req:has_body(3), cowboy_req:body_length(3), cowboy_req:read_body(3), cowboy_req:read_urlencoded_body(3), cowboy_req:read_part_body(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.read_part_body/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.read_part_body/index.html index 21947796..d08ee13e 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.read_part_body/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.read_part_body/index.html @@ -62,130 +62,70 @@

cowboy_req:read_part_body(3)

-

Name

-
-

cowboy_req:read_part_body - Read the current part’s body

-
-
-
+

cowboy_req:read_part_body - Read the current part's body

Description

-
-
-
-
read_part_body(Req :: cowboy_req:req())
-    -> read_part_body(Req, #{})
-
-read_part_body(Req :: cowboy_req:req(), Opts)
-    -> {ok,   Data :: binary(), Req}
-     | {more, Data :: binary(), Req}
-
-Opts :: cowboy_req:read_body_opts()
-

Read the body of the current part of the multipart message.

-

This function reads the request body and parses it as -multipart. Each parts of a multipart representation have -their own headers and body. This function returns the -body of the current part. Examples of multipart media types -are multipart/form-data and multipart/byteranges.

-

This function reads a chunk of the part’s body. A more tuple -is returned when more data remains to be read. Call the function -repeatedly until an ok tuple is returned to read the entire body.

-

Once a part has been read, it can not be read again.

-

Once the body has been read, Cowboy sets the content-length -header if it was not previously provided.

-
-
-
+
read_part_body(Req :: cowboy_req:req())
+    -> read_part_body(Req, #{})
+
+read_part_body(Req :: cowboy_req:req(), Opts)
+    -> {ok,   Data :: binary(), Req}
+     | {more, Data :: binary(), Req}
+
+Opts :: cowboy_req:read_body_opts()
+
+

Read the body of the current part of the multipart message.

+

This function reads the request body and parses it as multipart. Each parts of a multipart representation have their own headers and body. This function returns the body of the current part. Examples of multipart media types are multipart/form-data and multipart/byteranges.

+

This function reads a chunk of the part's body. A more tuple is returned when more data remains to be read. Call the function repeatedly until an ok tuple is returned to read the entire body.

+

Once a part has been read, it can not be read again.

+

Once the body has been read, Cowboy sets the content-length header if it was not previously provided.

+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-Opts -
-
-

-A map of body reading options. Please refer to -cowboy_req:read_body(3) -for details about each option. -

-

This function uses the same default options as the -cowboy_req:read_body(3) -function.

+
Opts
+

A map of body reading options. Please refer to cowboy_req:read_body(3) for details about each option.

+

This function uses the same default options as the cowboy_req:read_body(3) function.

-
-
- -
+

Return value

-
-

A more tuple is returned when there are more data to be read.

-

An ok tuple is returned when there are no more data to be read.

-

The data is always returned as a binary.

-

The Req object returned in the tuple must be used for that point -onward. It contains a more up to date representation of the request. -For example it may have an added content-length header once the -body has been read.

-
-
-
+

A more tuple is returned when there are more data to be read.

+

An ok tuple is returned when there are no more data to be read.

+

The data is always returned as a binary.

+

The Req object returned in the tuple must be used for that point onward. It contains a more up to date representation of the request. For example it may have an added content-length header once the body has been read.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. Replaces part_body/1,2. -

    +
    • 2.0: Function introduced. Replaces part_body/1,2.
      • -
-
-
-
+

Examples

-
-
-
Read a full part’s body
-
-
stream_body(Req0, Acc) ->
-    case cowboy_req:read_part_body(Req0) of
-        {more, Data, Req} ->
-            stream_body(Req, << Acc/binary, Data/binary >>);
-        {ok, Data, Req} ->
-            {ok, << Acc/binary, Data/binary >>, Req}
-    end.
-
-
Ensure a part’s body is smaller than 64KB
-
-
{ok, Body, Req} = cowboy_req:read_part_body(Req0, #{length => 64000}).
-
-
-
+
{ok, Body, Req} = cowboy_req:read_part_body(Req0, #{length => 64000}).
+

See also

-
-

cowboy_req(3), -cowboy_req:has_body(3), -cowboy_req:body_length(3), -cowboy_req:read_body(3), -cowboy_req:read_urlencoded_body(3), -cowboy_req:read_part(3)

-
- +

cowboy_req(3), cowboy_req:has_body(3), cowboy_req:body_length(3), cowboy_req:read_body(3), cowboy_req:read_urlencoded_body(3), cowboy_req:read_part(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.read_urlencoded_body/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.read_urlencoded_body/index.html index 23b33f3e..7f229d60 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.read_urlencoded_body/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.read_urlencoded_body/index.html @@ -62,126 +62,64 @@

cowboy_req:read_urlencoded_body(3)

-

Name

-
-

cowboy_req:read_urlencoded_body - Read and parse a urlencoded request body

-
-
-
+

cowboy_req:read_urlencoded_body - Read and parse a urlencoded request body

Description

-
-
-
-
read_urlencoded_body(Req :: cowboy_req:req())
-    -> read_urlencoded_body(Req, #{})
-
-read_urlencoded_body(Req :: cowboy_req:req(), Opts)
-    -> {ok, Body, Req}
-
-Opts :: cowboy_req:read_body_opts()
-Body :: [{Key :: binary(), Value :: binary() | true}]
-

Read and parse a urlencoded request body.

-

This function reads the request body and parses it as -application/x-www-form-urlencoded. It returns a list -of key/values.

-

The urlencoded media type is used by Web browsers when -submitting HTML forms using the POST method.

-

Cowboy needs to read the full body before parsing. By default -it will read bodies of size up to 64KB. It is possible to -provide options to read larger bodies if required.

-

Cowboy will automatically handle protocol details including -the expect header, chunked transfer-encoding and others.

-

Once the body has been read, Cowboy sets the content-length -header if it was not previously provided.

-

This function can only be called once. Calling it again will -result in undefined behavior.

-
-
-
+
read_urlencoded_body(Req :: cowboy_req:req())
+    -> read_urlencoded_body(Req, #{})
+
+read_urlencoded_body(Req :: cowboy_req:req(), Opts)
+    -> {ok, Body, Req}
+
+Opts :: cowboy_req:read_body_opts()
+Body :: [{Key :: binary(), Value :: binary() | true}]
+
+

Read and parse a urlencoded request body.

+

This function reads the request body and parses it as application/x-www-form-urlencoded. It returns a list of key/values.

+

The urlencoded media type is used by Web browsers when submitting HTML forms using the POST method.

+

Cowboy needs to read the full body before parsing. By default it will read bodies of size up to 64KB. It is possible to provide options to read larger bodies if required.

+

Cowboy will automatically handle protocol details including the expect header, chunked transfer-encoding and others.

+

Once the body has been read, Cowboy sets the content-length header if it was not previously provided.

+

This function can only be called once. Calling it again will result in undefined behavior.

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-Opts -
-
-

-A map of body reading options. Please refer to -cowboy_req:read_body(3) -for details about each option. -

-

This function defaults the length to 64KB and the period -to 5 seconds.

+
Opts
+

A map of body reading options. Please refer to cowboy_req:read_body(3) for details about each option.

+

This function defaults the length to 64KB and the period to 5 seconds.

-
-
- -
+

Return value

-
-

An ok tuple is returned containing a list of key/values found -in the body.

-

The Req object returned in the tuple must be used for that point -onward. It contains a more up to date representation of the request. -For example it may have an added content-length header once the -body has been read.

-
-
-
+

An ok tuple is returned containing a list of key/values found in the body.

+

The Req object returned in the tuple must be used for that point onward. It contains a more up to date representation of the request. For example it may have an added content-length header once the body has been read.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. Replaces body_qs/1,2. -

    +
    • 2.0: Function introduced. Replaces body_qs/1,2.
      • -
-
-
-
+

Examples

-
-
-
Read a urlencoded body
-
-
{ok, Body, Req} = cowboy_req:read_urlencoded_body(Req0),
-{_, Lang} = lists:keyfind(<<"lang">>, 1, Body).
-
-
Allow large urlencoded bodies
-
-
{ok, Body, Req} = cowboy_req:read_urlencoded_body(Req0, #{length => 1000000}).
-
-
-
+
{ok, Body, Req} = cowboy_req:read_urlencoded_body(Req0, #{length => 1000000}).
+

See also

-
-

cowboy_req(3), -cowboy_req:has_body(3), -cowboy_req:body_length(3), -cowboy_req:read_body(3), -cowboy_req:read_part(3), -cowboy_req:read_part_body(3)

-
- +

cowboy_req(3), cowboy_req:has_body(3), cowboy_req:body_length(3), cowboy_req:read_body(3), cowboy_req:read_part(3), cowboy_req:read_part_body(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.reply/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.reply/index.html index 602df6ad..564db588 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.reply/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.reply/index.html @@ -62,165 +62,87 @@

cowboy_req:reply(3)

-

Name

-
-

cowboy_req:reply - Send the response

-
-
-
+

cowboy_req:reply - Send the response

Description

-
-
-
-
reply(Status, Req :: cowboy_req:req())
-    -> reply(StatusCode, #{}, Req)
-
-reply(Status, Headers, Req :: cowboy_req:req())
-    -> Req
-
-reply(Status, Headers, Body, Req :: cowboy_req:req())
-    -> Req
-
-Status  :: cowboy:http_status()
-Headers :: cowboy:http_headers()
-Body    :: cowboy_req:resp_body()
-

Send the response.

-

The header names must be given as lowercase binary strings. -While header names are case insensitive, Cowboy requires them -to be given as lowercase to function properly.

-

Cowboy does not allow duplicate header names. Headers set -by this function may overwrite those set by set_resp_header/3 -and set_resp_headers/2.

-

Use cowboy_req:set_resp_cookie(3) -instead of this function to set cookies.

-

The reply/2,3 functions will send the body set previously, -if any. The reply/4 function always sends the given body, -overriding any previously set.

-

You do not need to set the content-length header when -sending a response body. Cowboy takes care of it automatically. -You should however provide a content-type header.

-

No further data can be transmitted after this function -returns. This includes the push mechanism. Attempting to -send two replies, or to push resources after a reply has -been sent, will result in an error.

-
-
-
+
reply(Status, Req :: cowboy_req:req())
+    -> reply(StatusCode, #{}, Req)
+
+reply(Status, Headers, Req :: cowboy_req:req())
+    -> Req
+
+reply(Status, Headers, Body, Req :: cowboy_req:req())
+    -> Req
+
+Status  :: cowboy:http_status()
+Headers :: cowboy:http_headers()
+Body    :: cowboy_req:resp_body()
+
+

Send the response.

+

The header names must be given as lowercase binary strings. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.

+

Cowboy does not allow duplicate header names. Headers set by this function may overwrite those set by set_resp_header/3 and set_resp_headers/2.

+

Use cowboy_req:set_resp_cookie(3) instead of this function to set cookies.

+

The reply/2,3 functions will send the body set previously, if any. The reply/4 function always sends the given body, overriding any previously set.

+

You do not need to set the content-length header when sending a response body. Cowboy takes care of it automatically. You should however provide a content-type header.

+

No further data can be transmitted after this function returns. This includes the push mechanism. Attempting to send two replies, or to push resources after a reply has been sent, will result in an error.

Arguments

-
-
-
-Status -
-
-

-The status code for the response. -

+
Status
+

The status code for the response.

-
-Headers -
-
-

-The response headers. -

+
Headers
+

The response headers.

-
-

Header names must be given as lowercase binary strings.

-
-
-Body -
-
-

-The body can be either a binary value, an iolist or a -sendfile tuple telling Cowboy to send the contents of -a file. -

+
+

Header names must be given as lowercase binary strings.

+
Body
+

The body can be either a binary value, an iolist or a sendfile tuple telling Cowboy to send the contents of a file.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

A new Req object is returned.

-

The returned Req object should be used from that point onward -as it contains updated information about the state of the request.

-
-
-
+

A new Req object is returned.

+

The returned Req object should be used from that point onward as it contains updated information about the state of the request.

Changelog

-
-
    -
  • -

    -2.0: Only the Req is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the Req is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Reply
-
-
Req = cowboy_req:reply(404, Req0).
-
-
Reply with custom headers
-
-
Req = cowboy_req:reply(401, #{
-    <<"www-authenticate">> => <<"Basic realm=\"erlang.org\"">>
-}, Req0).
-
-
Reply with custom headers and a body
-
-
Req = cowboy_req:reply(200, #{
-    <<"content-type">> => <<"text/plain">>
-}, "Hello world!", Req0).
-
-
-
+
Req = cowboy_req:reply(200, #{
+    <<"content-type">> => <<"text/plain">>
+}, "Hello world!", Req0).
+

See also

-
-

cowboy_req(3), -cowboy_req:set_resp_cookie(3), -cowboy_req:set_resp_header(3), -cowboy_req:set_resp_headers(3), -cowboy_req:set_resp_body(3), -cowboy_req:inform(3), -cowboy_req:stream_reply(3), -cowboy_req:push(3)

-
- +

cowboy_req(3), cowboy_req:set_resp_cookie(3), cowboy_req:set_resp_header(3), cowboy_req:set_resp_headers(3), cowboy_req:set_resp_body(3), cowboy_req:inform(3), cowboy_req:stream_reply(3), cowboy_req:push(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.resp_header/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.resp_header/index.html index 1c82f05d..cf70d271 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.resp_header/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.resp_header/index.html @@ -62,113 +62,58 @@

cowboy_req:resp_header(3)

-

Name

-
-

cowboy_req:resp_header - Response header

-
-
-
+

cowboy_req:resp_header - Response header

Description

-
-
-
-
resp_header(Name, Req)          -> resp_header(Name, Req, undefined)
-resp_header(Name, Req, Default) -> binary() | Default
-
-Name    :: binary()          %% lowercase; case insensitive
-Req     :: cowboy_req:req()
-Default :: any()
-

Return the value for the given response header.

-

The response header must have been set previously using -cowboy_req:set_resp_header(3) or -cowboy_req:set_resp_headers(3).

-

The header name must be given as a lowercase binary string. -While header names are case insensitive, Cowboy requires them -to be given as lowercase to function properly.

-
-
-
+
resp_header(Name, Req)          -> resp_header(Name, Req, undefined)
+resp_header(Name, Req, Default) -> binary() | Default
+
+Name    :: binary()          %% lowercase; case insensitive
+Req     :: cowboy_req:req()
+Default :: any()
+
+

Return the value for the given response header.

+

The response header must have been set previously using cowboy_req:set_resp_header(3) or cowboy_req:set_resp_headers(3).

+

The header name must be given as a lowercase binary string. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.

Arguments

-
-
-
-Name -
-
-

-Desired response header name as a lowercase binary string. -

+
Name
+

Desired response header name as a lowercase binary string.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-Default -
-
-

-Default value returned when the header is missing. -

+
Default
+

Default value returned when the header is missing.

-
-
- -
+

Return value

-
-

The header value is returned as a binary string. When the -header is missing, the default argument is returned.

-
-
-
+

The header value is returned as a binary string. When the header is missing, the default argument is returned.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. -

    +
    • 2.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the content-type response header
-
-
Type = cowboy_req:resp_header(<<"content-type">>, Req).
-
-
Get the content-type response header with a default value
-
-
Type = cowboy_req:resp_header(<<"content-type">>, Req, <<"text/html">>).
-
-
-
+
Type = cowboy_req:resp_header(<<"content-type">>, Req, <<"text/html">>).
+

See also

-
-

cowboy_req(3), -cowboy_req:resp_headers(3), -cowboy_req:set_resp_header(3), -cowboy_req:set_resp_headers(3)

-
- +

cowboy_req(3), cowboy_req:resp_headers(3), cowboy_req:set_resp_header(3), cowboy_req:set_resp_headers(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.resp_headers/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.resp_headers/index.html index dcd1aca6..19110153 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.resp_headers/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.resp_headers/index.html @@ -62,79 +62,38 @@

cowboy_req:resp_headers(3)

-

Name

-
-

cowboy_req:resp_headers - Response headers

-
-
-
+

cowboy_req:resp_headers - Response headers

Description

-
-
-
-
resp_headers(Req :: cowboy_req:req()) -> cowboy:http_headers()
-

Return all response headers.

-
-
-
+
resp_headers(Req :: cowboy_req:req()) -> cowboy:http_headers()
+
+

Return all response headers.

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

Headers are returned as a map with keys being lowercase -binary strings, and values as binary strings.

-
-
-
+

Headers are returned as a map with keys being lowercase binary strings, and values as binary strings.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. -

    +
    • 2.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get all response headers
-
-
Headers = cowboy_req:resp_headers(Req).
-
-
-
+
Headers = cowboy_req:resp_headers(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:resp_header(3), -cowboy_req:set_resp_header(3), -cowboy_req:set_resp_headers(3)

-
- +

cowboy_req(3), cowboy_req:resp_header(3), cowboy_req:set_resp_header(3), cowboy_req:set_resp_headers(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.scheme/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.scheme/index.html index 4c83810f..94763a2c 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.scheme/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.scheme/index.html @@ -62,89 +62,52 @@

cowboy_req:scheme(3)

-

Name

-
-

cowboy_req:scheme - URI scheme

-
-
-
+

cowboy_req:scheme - URI scheme

Description

-
-
-
-
scheme(Req :: cowboy_req:req()) -> Scheme :: binary()
-

Return the scheme of the effective request URI.

-

The scheme can also be obtained using pattern matching:

-
-
-
#{scheme := Scheme} = Req.
-
-
-
+
#{scheme := Scheme} = Req.
+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The scheme is returned as a binary. It is case insensitive.

-

Cowboy will only set the scheme to <<"http">> or <<"https">>.

-
-
-
+

The scheme is returned as a binary. It is case insensitive.

+

Cowboy will only set the scheme to <<"http">> or <<"https">>.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. -

    +
    • 2.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Redirect HTTP to HTTPS
-
-
init(Req0=#{scheme := <<"http">>}, State) ->
-    Req = cowboy_req:reply(302, #{
-        <<"location">> => cowboy_req:uri(Req, #{scheme => <<"https">>})
-    }, Req0),
-    {ok, Req, State};
-init(Req, State) ->
-    {cowboy_rest, Req, State}.
-
-
-
+
init(Req0=#{scheme := <<"http">>}, State) ->
+    Req = cowboy_req:reply(302, #{
+        <<"location">> => cowboy_req:uri(Req, #{scheme => <<"https">>})
+    }, Req0),
+    {ok, Req, State};
+init(Req, State) ->
+    {cowboy_rest, Req, State}.
+

See also

-
-

cowboy_req(3)

-
- +

cowboy_req(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_body/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_body/index.html index da393ed3..f48bf4be 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_body/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_body/index.html @@ -62,138 +62,79 @@

cowboy_req:set_resp_body(3)

-

Name

-
-

cowboy_req:set_resp_body - Set the response body

-
-
-
+

cowboy_req:set_resp_body - Set the response body

Description

-
-
-
-
set_resp_body(Body, Req :: cowboy_req:req())
-        -> Req
-
-Body :: cowboy_req:resp_body()
-

Set the response body.

-

The response body will be sent when a reply is initiated. -Note that the functions stream_reply/2,3 and reply/4 -will override the body set by this function.

-

This function can also be used to remove a response body -that was set previously. To do so, simply call this function -with an empty body.

-
-
-
+
set_resp_body(Body, Req :: cowboy_req:req())
+	-> Req
+
+Body :: cowboy_req:resp_body()
+
+

Set the response body.

+

The response body will be sent when a reply is initiated. Note that the functions stream_reply/2,3 and reply/4 will override the body set by this function.

+

This function can also be used to remove a response body that was set previously. To do so, simply call this function with an empty body.

Arguments

-
-
-
-Body -
-
-

-The body can be either a binary value, an iolist or a -sendfile tuple telling Cowboy to send the contents of -a file. -

+
Body
+

The body can be either a binary value, an iolist or a sendfile tuple telling Cowboy to send the contents of a file.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

A new Req object is returned.

-

The returned Req object must be used from that point onward, -otherwise the body will not be sent in the response.

-
-
-
+

A new Req object is returned.

+

The returned Req object must be used from that point onward, otherwise the body will not be sent in the response.

Changelog

-
-
    -
  • -

    -2.0: The function now accepts a sendfile tuple. -

    +
    • 2.0: The function now accepts a sendfile tuple.
      • -
    • -

      -2.0: The set_resp_body_fun/2,3 functions were removed. -

      +
    • 2.0: The set_resp_body_fun/2,3 functions were removed.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Set the response body
-
-
Req = cowboy_req:set_resp_body(<<"Hello world!">>, Req0).
-
-
Set the response body as an iolist
-
-
Req = cowboy_req:set_resp_body([
-    "<html><head><title>",
-    page_title(),
-    "</title></head><body>",
-    page_body(),
-    "</body></html>"
-], Req0).
-
-
Tell Cowboy to send data from a file
-
-
{ok, #file_info{size=Size}} = file:read_file_info(Filename),
-Req = cowboy_req:set_resp_body({sendfile, 0, Size, Filename}, Req0).
-
-
Clear any previously set response body
-
-
Req = cowboy_req:set_resp_body(<<>>, Req0).
-
-
-
+
Req = cowboy_req:set_resp_body(<<>>, Req0).
+

See also

-
-

cowboy_req(3), -cowboy_req:set_resp_header(3), -cowboy_req:set_resp_headers(3), -cowboy_req:reply(3), -cowboy_req:stream_reply(3)

-
- +

cowboy_req(3), cowboy_req:set_resp_header(3), cowboy_req:set_resp_headers(3), cowboy_req:reply(3), cowboy_req:stream_reply(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_cookie/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_cookie/index.html index d26cd71d..f539ceda 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_cookie/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_cookie/index.html @@ -62,167 +62,104 @@

cowboy_req:set_resp_cookie(3)

-

Name

-
-

cowboy_req:set_resp_cookie - Set a cookie

-
-
-
+

cowboy_req:set_resp_cookie - Set a cookie

Description

-
-
-
-
set_resp_cookie(Name, Value, Req :: cowboy_req:req())
-    -> set_resp_cookie(Name, Value, [], Req)
-
-set_resp_cookie(Name, Value, Req :: cowboy_req:req(), Opts)
-    -> Req
-
-Name  :: binary()                  %% case sensitive
-Value :: iodata()                  %% case sensitive
-Opts  :: cow_cookie:cookie_opts()
-

Set a cookie to be sent with the response.

-

Note that cookie names are case sensitive.

-
-
-
+
set_resp_cookie(Name, Value, Req :: cowboy_req:req())
+    -> set_resp_cookie(Name, Value, [], Req)
+
+set_resp_cookie(Name, Value, Req :: cowboy_req:req(), Opts)
+    -> Req
+
+Name  :: binary()                  %% case sensitive
+Value :: iodata()                  %% case sensitive
+Opts  :: cow_cookie:cookie_opts()
+
+

Set a cookie to be sent with the response.

+

Note that cookie names are case sensitive.

Arguments

-
-
-
-Name -
-
-

-Cookie name. -

+
Name
+

Cookie name.

-
-Value -
-
-

-Cookie value. -

+
Value
+

Cookie value.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-Opts -
-
-

-Cookie options. -

+
Opts
+

Cookie options.

-
-
- -
+

Return value

-
-

A new Req object is returned.

-

The returned Req object must be used from that point onward, -otherwise the cookie will not be sent in the response.

-
-
-
+

A new Req object is returned.

+

The returned Req object must be used from that point onward, otherwise the cookie will not be sent in the response.

Changelog

-
-
    -
  • -

    -2.0: set_resp_cookie/3 introduced as an alias to set_resp_cookie/4 with no options. -

    +
    • 2.0: set_resp_cookie/3 introduced as an alias to set_resp_cookie/4 with no options.
      • -
    • -

      -2.0: The first argument type is now binary() instead of iodata(). -

      +
    • 2.0: The first argument type is now binary() instead of iodata().
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Set a session cookie
-
-
SessionID = base64:encode(crypto:strong_rand_bytes(32)),
-Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, Req0).
-
-
Set a cookie with an expiration time
-
-
Req = cowboy_req:set_resp_cookie(<<"lang">>, <<"fr-FR">>,
-    Req0, #{max_age => 3600}).
-
-
Delete a cookie
-
-
Req = cowboy_req:set_resp_cookie(<<"sessionid">>, <<>>,
-    Req0, #{max_age => 0}).
-
-
Set a cookie for a specific domain and path
-
-
Req = cowboy_req:set_resp_cookie(<<"inaccount">>, <<"1">>,
-    Req0, #{domain => "my.example.org", path => "/account"}).
-
-
Restrict a cookie to HTTPS
-
-
SessionID = base64:encode(crypto:strong_rand_bytes(32)),
-Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID,
-    Req0, #{secure => true}).
-
-
Restrict a cookie to HTTP
-
-
SessionID = base64:encode(crypto:strong_rand_bytes(32)),
-Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID,
-    Req0, #{http_only => true}).
-
-
-
+
SessionID = base64:encode(crypto:strong_rand_bytes(32)),
+Req = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID,
+    Req0, #{http_only => true}).
+

See also

-
-

cowboy_req(3), -cowboy_req:set_resp_header(3), -cowboy_req:set_resp_headers(3), -cowboy_req:reply(3), -cowboy_req:stream_reply(3)

-
- +

cowboy_req(3), cowboy_req:set_resp_header(3), cowboy_req:set_resp_headers(3), cowboy_req:reply(3), cowboy_req:stream_reply(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_header/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_header/index.html index 5877b7f5..fad10beb 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_header/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_header/index.html @@ -62,121 +62,60 @@

cowboy_req:set_resp_header(3)

-

Name

-
-

cowboy_req:set_resp_header - Set a response header

-
-
-
+

cowboy_req:set_resp_header - Set a response header

Description

-
-
-
-
set_resp_header(Name, Value, Req :: cowboy_req:req())
-        -> Req
-
-Name  :: binary()  %% lowercase; case insensitive
-Value :: iodata()  %% case depends on header
-

Set a header to be sent with the response.

-

The header name must be given as a lowercase binary string. -While header names are case insensitive, Cowboy requires them -to be given as lowercase to function properly.

-

Cowboy does not allow duplicate header names. Headers set -by this function may be overwritten by those set from the -reply functions.

-

Use cowboy_req:set_resp_cookie(3) -instead of this function to set cookies.

-
-
-
+
set_resp_header(Name, Value, Req :: cowboy_req:req())
+	-> Req
+
+Name  :: binary()  %% lowercase; case insensitive
+Value :: iodata()  %% case depends on header
+
+

Set a header to be sent with the response.

+

The header name must be given as a lowercase binary string. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.

+

Cowboy does not allow duplicate header names. Headers set by this function may be overwritten by those set from the reply functions.

+

Use cowboy_req:set_resp_cookie(3) instead of this function to set cookies.

Arguments

-
-
-
-Name -
-
-

-Header name as a lowercase binary string. -

+
Name
+

Header name as a lowercase binary string.

-
-Value -
-
-

-Header value. -

+
Value
+

Header value.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

A new Req object is returned.

-

The returned Req object must be used from that point onward, -otherwise the header will not be sent in the response.

-
-
-
+

A new Req object is returned.

+

The returned Req object must be used from that point onward, otherwise the header will not be sent in the response.

Changelog

-
-
    -
  • -

    -1.0: Function introduced. -

    +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Set a header in the response
-
-
Req = cowboy_req:set_resp_header(<<"allow">>, "GET", Req0).
-
-
Construct a header using iolists
-
-
Req = cowboy_req:set_resp_header(<<"allow">>,
-    [allowed_methods(), ", OPTIONS"], Req0).
-
-
-
+
Req = cowboy_req:set_resp_header(<<"allow">>,
+    [allowed_methods(), ", OPTIONS"], Req0).
+

See also

-
-

cowboy_req(3), -cowboy_req:set_resp_cookie(3), -cowboy_req:set_resp_headers(3), -cowboy_req:has_resp_header(3), -cowboy_req:resp_header(3), -cowboy_req:resp_headers(3), -cowboy_req:delete_resp_header(3), -cowboy_req:reply(3), -cowboy_req:stream_reply(3)

-
- +

cowboy_req(3), cowboy_req:set_resp_cookie(3), cowboy_req:set_resp_headers(3), cowboy_req:has_resp_header(3), cowboy_req:resp_header(3), cowboy_req:resp_headers(3), cowboy_req:delete_resp_header(3), cowboy_req:reply(3), cowboy_req:stream_reply(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_headers/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_headers/index.html index 9b76cc9f..e22407e6 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_headers/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.set_resp_headers/index.html @@ -62,109 +62,51 @@

cowboy_req:set_resp_headers(3)

-

Name

-
-

cowboy_req:set_resp_headers - Set several response headers

-
-
-
+

cowboy_req:set_resp_headers - Set several response headers

Description

-
-
-
-
set_resp_headers(Headers, Req :: cowboy_req:req())
-    -> Req
-
-Headers :: cowboy:http_headers()
-

Set several headers to be sent with the response.

-

The header name must be given as a lowercase binary string. -While header names are case insensitive, Cowboy requires them -to be given as lowercase to function properly.

-

Cowboy does not allow duplicate header names. Headers set -by this function may be overwritten by those set from the -reply functions. Likewise, headers set by this function may -overwrite headers that were set previously.

-

Use cowboy_req:set_resp_cookie(3) -instead of this function to set cookies.

-
-
-
+
set_resp_headers(Headers, Req :: cowboy_req:req())
+    -> Req
+
+Headers :: cowboy:http_headers()
+
+

Set several headers to be sent with the response.

+

The header name must be given as a lowercase binary string. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.

+

Cowboy does not allow duplicate header names. Headers set by this function may be overwritten by those set from the reply functions. Likewise, headers set by this function may overwrite headers that were set previously.

+

Use cowboy_req:set_resp_cookie(3) instead of this function to set cookies.

Arguments

-
-
-
-Headers -
-
-

-Headers as a map with keys being lowercase binary strings, -and values as binary strings. -

+
Headers
+

Headers as a map with keys being lowercase binary strings, and values as binary strings.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

A new Req object is returned.

-

The returned Req object must be used from that point onward, -otherwise the headers will not be sent in the response.

-
-
-
+

A new Req object is returned.

+

The returned Req object must be used from that point onward, otherwise the headers will not be sent in the response.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. -

    +
    • 2.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Set several response headers
-
-
Req = cowboy_req:set_resp_headers(#{
-    <<"content-type">>     => <<"text/html">>,
-    <<"content-encoding">> => <<"gzip">>
-}, Req0).
-
-
-
+
Req = cowboy_req:set_resp_headers(#{
+    <<"content-type">>     => <<"text/html">>,
+    <<"content-encoding">> => <<"gzip">>
+}, Req0).
+

See also

-
-

cowboy_req(3), -cowboy_req:set_resp_cookie(3), -cowboy_req:set_resp_header(3), -cowboy_req:has_resp_header(3), -cowboy_req:resp_header(3), -cowboy_req:resp_headers(3), -cowboy_req:delete_resp_header(3), -cowboy_req:reply(3), -cowboy_req:stream_reply(3)

-
- +

cowboy_req(3), cowboy_req:set_resp_cookie(3), cowboy_req:set_resp_header(3), cowboy_req:has_resp_header(3), cowboy_req:resp_header(3), cowboy_req:resp_headers(3), cowboy_req:delete_resp_header(3), cowboy_req:reply(3), cowboy_req:stream_reply(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.sock/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.sock/index.html index 8441d5cb..ca729f96 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.sock/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.sock/index.html @@ -62,86 +62,47 @@

cowboy_req:sock(3)

-

Name

-
-

cowboy_req:sock - Socket address and port

-
-
-
+

cowboy_req:sock - Socket address and port

Description

-
-
-
-
sock(Req :: cowboy_req:req()) -> Info
+
sock(Req :: cowboy_req:req()) -> Info
 
-Info :: {inet:ip_address(), inet:port_number()}
-

Return the socket’s IP address and port number.

-

The socket information can also be obtained using pattern matching:

-
-
-
#{sock := {IP, Port}} = Req.
-
-
-
+
#{sock := {IP, Port}} = Req.
+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The socket’s local IP address and port number.

-
-
-
+

The socket's local IP address and port number.

Changelog

-
-
    -
  • -

    -2.1: Function introduced. -

    +
    • 2.1: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the socket’s IP address and port number.
-
-
{IP, Port} = cowboy_req:sock(Req).
-
-
-
+
{IP, Port} = cowboy_req:sock(Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:peer(3), -cowboy_req:cert(3)

-
- +

cowboy_req(3), cowboy_req:peer(3), cowboy_req:cert(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.stream_body/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.stream_body/index.html index 350c7e27..cd264e0d 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.stream_body/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.stream_body/index.html @@ -62,119 +62,56 @@

cowboy_req:stream_body(3)

-

Name

-
-

cowboy_req:stream_body - Stream the response body

-
-
-
+

cowboy_req:stream_body - Stream the response body

Description

-
-
-
-
stream_body(Data, IsFin, Req :: cowboy_req:req()) -> ok
-
-Data  :: iodata()
-IsFin :: fin | nofin
-

Stream the response body.

-

This function may be called as many times as needed after -initiating a response using the -cowboy_req:stream_reply(3) -function.

-

The second argument indicates if this call is the final -call. Use the nofin value until you know no more data -will be sent. The final call should use fin (possibly -with an empty data value) or be a call to the -cowboy_req:stream_trailers(3) -function.

-

Note that not using fin for the final call is not an -error; Cowboy will take care of it when the request -handler terminates if needed. Depending on the resource -it may however be more efficient to do it as early as -possible.

-

You do not need to handle HEAD requests specifically as -Cowboy will ensure no data is sent when you call this function.

-
-
-
+
stream_body(Data, IsFin, Req :: cowboy_req:req()) -> ok
+
+Data  :: iodata()
+IsFin :: fin | nofin
+
+

Stream the response body.

+

This function may be called as many times as needed after initiating a response using the cowboy_req:stream_reply(3) function.

+

The second argument indicates if this call is the final call. Use the nofin value until you know no more data will be sent. The final call should use fin (possibly with an empty data value) or be a call to the cowboy_req:stream_trailers(3) function.

+

Note that not using fin for the final call is not an error; Cowboy will take care of it when the request handler terminates if needed. Depending on the resource it may however be more efficient to do it as early as possible.

+

You do not need to handle HEAD requests specifically as Cowboy will ensure no data is sent when you call this function.

Arguments

-
-
-
-Data -
-
-

-The data to be sent. -

+
Data
+

The data to be sent.

-
-IsFin -
-
-

-A flag indicating whether this is the final piece of data -to be sent. -

+
IsFin
+

A flag indicating whether this is the final piece of data to be sent.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The atom ok is always returned. It can be safely ignored.

-
-
-
+

The atom ok is always returned. It can be safely ignored.

Changelog

-
-
    -
  • -

    -2.0: Function introduced. Replaces chunk/2. -

    +
    • 2.0: Function introduced. Replaces chunk/2.
      • -
-
-
-
+

Examples

-
-
-
Stream the response body
-
-
Req = cowboy_req:stream_reply(200, #{
-    <<"content-type">> => <<"text/plain">>
-}, Req0),
-cowboy_req:stream_body(<<"Hello\n">>, nofin, Req),
-timer:sleep(1000),
-cowboy_req:stream_body(<<"World!\n">>, fin, Req).
-
-
-
+
Req = cowboy_req:stream_reply(200, #{
+    <<"content-type">> => <<"text/plain">>
+}, Req0),
+cowboy_req:stream_body(<<"Hello\n">>, nofin, Req),
+timer:sleep(1000),
+cowboy_req:stream_body(<<"World!\n">>, fin, Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:stream_reply(3), -cowboy_req:stream_trailers(3)

-
- +

cowboy_req(3), cowboy_req:stream_reply(3), cowboy_req:stream_trailers(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.stream_reply/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.stream_reply/index.html index 711b4595..a791e1ae 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.stream_reply/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.stream_reply/index.html @@ -62,152 +62,76 @@

cowboy_req:stream_reply(3)

-

Name

-
-

cowboy_req:stream_reply - Send the response headers

-
-
-
+

cowboy_req:stream_reply - Send the response headers

Description

-
-
-
-
stream_reply(Status, Req :: cowboy_req:req())
-    -> stream_reply(StatusCode, #{}, Req)
-
-stream_reply(Status, Headers, Req :: cowboy_req:req())
-    -> Req
-
-Status  :: cowboy:http_status()
-Headers :: cowboy:http_headers()
-

Send the response headers.

-

The header names must be given as lowercase binary strings. -While header names are case insensitive, Cowboy requires them -to be given as lowercase to function properly.

-

Cowboy does not allow duplicate header names. Headers set -by this function may overwrite those set by set_resp_header/3.

-

Use cowboy_req:set_resp_cookie(3) -instead of this function to set cookies.

-

If a response body was set before calling this function, -it will not be sent.

-

Use cowboy_req:stream_body(3) -to stream the response body and optionally -cowboy_req:stream_trailers(3) -to send response trailer field values.

-

You may want to set the content-length header when using -this function, if it is known in advance. This will allow -clients using HTTP/2 and HTTP/1.0 to process the response -more efficiently.

-

The streaming method varies depending on the protocol being -used. HTTP/2 will use the usual DATA frames. HTTP/1.1 will -use chunked transfer-encoding. HTTP/1.0 will send the body -unmodified and close the connection at the end if no -content-length was set.

-

It is not possible to push resources after this function -returns. Any attempt will result in an error.

-
-
-
+
stream_reply(Status, Req :: cowboy_req:req())
+    -> stream_reply(StatusCode, #{}, Req)
+
+stream_reply(Status, Headers, Req :: cowboy_req:req())
+    -> Req
+
+Status  :: cowboy:http_status()
+Headers :: cowboy:http_headers()
+
+

Send the response headers.

+

The header names must be given as lowercase binary strings. While header names are case insensitive, Cowboy requires them to be given as lowercase to function properly.

+

Cowboy does not allow duplicate header names. Headers set by this function may overwrite those set by set_resp_header/3.

+

Use cowboy_req:set_resp_cookie(3) instead of this function to set cookies.

+

If a response body was set before calling this function, it will not be sent.

+

Use cowboy_req:stream_body(3) to stream the response body and optionally cowboy_req:stream_trailers(3) to send response trailer field values.

+

You may want to set the content-length header when using this function, if it is known in advance. This will allow clients using HTTP/2 and HTTP/1.0 to process the response more efficiently.

+

The streaming method varies depending on the protocol being used. HTTP/2 will use the usual DATA frames. HTTP/1.1 will use chunked transfer-encoding. HTTP/1.0 will send the body unmodified and close the connection at the end if no content-length was set.

+

It is not possible to push resources after this function returns. Any attempt will result in an error.

Arguments

-
-
-
-Status -
-
-

-The status code for the response. -

+
Status
+

The status code for the response.

-
-Headers -
-
-

-The response headers. -

+
Headers
+

The response headers.

-
-

Header names must be given as lowercase binary strings.

-
-
-Req -
-
-

-The Req object. -

+
+

Header names must be given as lowercase binary strings.

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

A new Req object is returned.

-

The returned Req object must be used from that point onward -in order to be able to stream the response body.

-
-
-
+

A new Req object is returned.

+

The returned Req object must be used from that point onward in order to be able to stream the response body.

Changelog

-
-
    -
  • -

    -2.0: Only the Req is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the Req is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -2.0: Function introduced. Replaces chunked_reply/1,2. -

      +
    • 2.0: Function introduced. Replaces chunked_reply/1,2.
      • -
-
-
-
+

Examples

-
-
-
Initiate the response
-
-
Req = cowboy_req:stream_reply(200, Req0).
-
-
Stream the response with custom headers
-
-
Req = cowboy_req:stream_reply(200, #{
-    <<"content-type">> => <<"text/plain">>
-}, Req0),
-cowboy_req:stream_body(<<"Hello\n">>, nofin, Req),
-timer:sleep(1000),
-cowboy_req:stream_body(<<"World!\n">>, fin, Req).
-
-
-
+
Req = cowboy_req:stream_reply(200, #{
+    <<"content-type">> => <<"text/plain">>
+}, Req0),
+cowboy_req:stream_body(<<"Hello\n">>, nofin, Req),
+timer:sleep(1000),
+cowboy_req:stream_body(<<"World!\n">>, fin, Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:set_resp_cookie(3), -cowboy_req:set_resp_header(3), -cowboy_req:set_resp_headers(3), -cowboy_req:inform(3), -cowboy_req:reply(3), -cowboy_req:stream_body(3), -cowboy_req:stream_trailers(3), -cowboy_req:push(3)

-
- +

cowboy_req(3), cowboy_req:set_resp_cookie(3), cowboy_req:set_resp_header(3), cowboy_req:set_resp_headers(3), cowboy_req:inform(3), cowboy_req:reply(3), cowboy_req:stream_body(3), cowboy_req:stream_trailers(3), cowboy_req:push(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.stream_trailers/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.stream_trailers/index.html index c65aa4ef..f1840c58 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.stream_trailers/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.stream_trailers/index.html @@ -62,107 +62,55 @@

cowboy_req:stream_trailers(3)

-

Name

-
-

cowboy_req:stream_trailers - Send the response trailers

-
-
-
+

cowboy_req:stream_trailers - Send the response trailers

Description

-
-
-
-
stream_trailers(Trailers, Req :: cowboy_req:req()) -> ok
-
-Trailers :: cowboy:http_headers()
-

Send the response trailers and terminate the stream.

-

This function can only be called once, after initiating -a response using -cowboy_req:stream_reply(3) -and sending zero or more body chunks using -cowboy_req:stream_body(3) -with the nofin argument set. The function stream_trailers/2 -implies fin and automatically terminate the response.

-

You must list all field names sent in trailers in the -trailer header, otherwise they might be dropped by intermediaries -or clients.

-
-
-
+
stream_trailers(Trailers, Req :: cowboy_req:req()) -> ok
+
+Trailers :: cowboy:http_headers()
+
+

Send the response trailers and terminate the stream.

+

This function can only be called once, after initiating a response using cowboy_req:stream_reply(3) and sending zero or more body chunks using cowboy_req:stream_body(3) with the nofin argument set. The function stream_trailers/2 implies fin and automatically terminate the response.

+

You must list all field names sent in trailers in the trailer header, otherwise they might be dropped by intermediaries or clients.

Arguments

-
-
-
-Trailers -
-
-

-Trailer field values to be sent. -

+
Trailers
+

Trailer field values to be sent.

-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The atom ok is always returned. It can be safely ignored.

-
-
-
+

The atom ok is always returned. It can be safely ignored.

Changelog

-
-
    -
  • -

    -2.2: Function introduced. -

    +
    • 2.2: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Stream a response body with trailers
-
-
Req = cowboy_req:stream_reply(200, #{
-    <<"content-type">> => <<"text/plain">>,
-    <<"trailer">> => <<"expires, content-md5">>
-}, Req0),
-cowboy_req:stream_body(<<"Hello\n">>, nofin, Req),
-timer:sleep(1000),
-cowboy_req:stream_body(<<"World!\n">>, nofin, Req).
-cowboy_req:stream_trailers(#{
-    <<"expires">> => <<"Sun, 10 Dec 2017 19:13:47 GMT">>,
-    <<"content-md5">> => <<"fbf68a8e34b2ded53bba54e68794b4fe">>
-}, Req).
-
-
-
+
Req = cowboy_req:stream_reply(200, #{
+    <<"content-type">> => <<"text/plain">>,
+    <<"trailer">> => <<"expires, content-md5">>
+}, Req0),
+cowboy_req:stream_body(<<"Hello\n">>, nofin, Req),
+timer:sleep(1000),
+cowboy_req:stream_body(<<"World!\n">>, nofin, Req).
+cowboy_req:stream_trailers(#{
+    <<"expires">> => <<"Sun, 10 Dec 2017 19:13:47 GMT">>,
+    <<"content-md5">> => <<"fbf68a8e34b2ded53bba54e68794b4fe">>
+}, Req).
+

See also

-
-

cowboy_req(3), -cowboy_req:stream_reply(3), -cowboy_req:stream_body(3)

-
- +

cowboy_req(3), cowboy_req:stream_reply(3), cowboy_req:stream_body(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.uri/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.uri/index.html index 90a435e3..73ab872d 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.uri/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.uri/index.html @@ -62,177 +62,106 @@

cowboy_req:uri(3)

-

Name

-
-

cowboy_req:uri - Reconstructed URI

-
-
-
+

cowboy_req:uri - Reconstructed URI

Description

-
-
-
-
uri(Req :: cowboy_req:req())       -> uri(Req, #{})
-uri(Req :: cowboy_req:req(), Opts) -> URI :: iodata()
-
-Opts :: #{
-    scheme   => iodata()           | undefined,
-    host     => iodata()           | undefined,
-    port     => inet:port_number() | undefined,
-    path     => iodata()           | undefined,
-    qs       => iodata()           | undefined,
-    fragment => iodata()           | undefined
-}
-

Reconstruct the effective request URI, optionally modifying components.

-

By default Cowboy will build a URI using the components found -in the request. Options allow disabling or replacing individual -components.

-
-
-
+
uri(Req :: cowboy_req:req())       -> uri(Req, #{})
+uri(Req :: cowboy_req:req(), Opts) -> URI :: iodata()
+
+Opts :: #{
+    scheme   => iodata()           | undefined,
+    host     => iodata()           | undefined,
+    port     => inet:port_number() | undefined,
+    path     => iodata()           | undefined,
+    qs       => iodata()           | undefined,
+    fragment => iodata()           | undefined
+}
+
+

Reconstruct the effective request URI, optionally modifying components.

+

By default Cowboy will build a URI using the components found in the request. Options allow disabling or replacing individual components.

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-Opts -
-
-

-Map for overriding individual components. -

-

To replace a component, provide its new value as a binary -string or an iolist. To disable a component, set its value -to undefined.

-

As this function always returns a valid URI, there are some -things to note:

-
    -
  • -

    -Disabling the host also disables the scheme and port. -

    +
    Opts
    +

    Map for overriding individual components.

    +

    To replace a component, provide its new value as a binary string or an iolist. To disable a component, set its value to undefined.

    +

    As this function always returns a valid URI, there are some things to note:

    +
    • Disabling the host also disables the scheme and port.
      • -
    • -

      -There is no fragment component by default as these are - not sent with the request. -

      +
    • There is no fragment component by default as these are not sent with the request.
      • -
    • -

      -The port number may not appear in the resulting URI if - it is the default port for the given scheme (http: 80; https: 443). -

      +
    • The port number may not appear in the resulting URI if it is the default port for the given scheme (http: 80; https: 443).
      • -
+
-
-
- -
+

Return value

-
-

The reconstructed URI is returned as an iolist or a binary string.

-
-
-
+

The reconstructed URI is returned as an iolist or a binary string.

Changelog

-
-
    -
  • -

    -2.0: Individual components can be replaced or disabled. -

    +
    • 2.0: Individual components can be replaced or disabled.
      • -
    • -

      -2.0: Only the URI is returned, it is no longer wrapped in a tuple. -

      +
    • 2.0: Only the URI is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -2.0: Function introduced. Replaces host_url/1 and url/1. -

      +
    • 2.0: Function introduced. Replaces host_url/1 and url/1.
      • -
-
-
-
+

Examples

-
-

With an effective request URI http://example.org/path/to/res?edit=1 -we can have:

-
-
Protocol relative form
-
-
%% //example.org/path/to/res?edit=1
-cowboy_req:uri(Req, #{scheme => undefined}).
-
-
Serialized origin for use in the origin header
-
-
%% http://example.org
-cowboy_req:uri(Req, #{path => undefined, qs => undefined}).
-
-
HTTP/1.1 origin form (path and query string only)
-
-
%% /path/to/res?edit=1
-cowboy_req:uri(Req, #{host => undefined}).
-
-
Add a fragment to the URI
-
-
%% http://example.org/path/to/res?edit=1#errors
-cowboy_req:uri(Req, #{fragment => <<"errors">>}).
-
-
Ensure the scheme is HTTPS
-
-
%% https://example.org/path/to/res?edit=1
-cowboy_req:uri(Req, #{scheme => <<"https">>}).
-
-
Convert the URI to a binary string
-
-
iolist_to_binary(cowboy_req:uri(Req)).
-
-
-
+
iolist_to_binary(cowboy_req:uri(Req)).
+

See also

-
-

cowboy_req(3), -cowboy_req:scheme(3), -cowboy_req:host(3), -cowboy_req:port(3), -cowboy_req:path(3), -cowboy_req:qs(3)

-
- +

cowboy_req(3), cowboy_req:scheme(3), cowboy_req:host(3), cowboy_req:port(3), cowboy_req:path(3), cowboy_req:qs(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req.version/index.html b/docs/en/cowboy/2.3/manual/cowboy_req.version/index.html index 82d3d006..4fb41dc0 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req.version/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req.version/index.html @@ -62,88 +62,47 @@

cowboy_req:version(3)

-

Name

-
-

cowboy_req:version - HTTP version

-
-
-
+

cowboy_req:version - HTTP version

Description

-
-
-
-
version(Req :: cowboy_req:req()) -> Version :: cowboy:http_version()
-

Return the HTTP version used for the request.

-

The version can also be obtained using pattern matching:

-
-
-
#{version := Version} = Req.
-
-
-
+
#{version := Version} = Req.
+

Arguments

-
-
-
-Req -
-
-

-The Req object. -

+
Req
+

The Req object.

-
-
- -
+

Return value

-
-

The HTTP version used for the request is returned as an -atom. It is provided for informative purposes only.

-
-
-
+

The HTTP version used for the request is returned as an atom. It is provided for informative purposes only.

Changelog

-
-
    -
  • -

    -2.0: Only the version is returned, it is no longer wrapped in a tuple. -

    +
    • 2.0: Only the version is returned, it is no longer wrapped in a tuple.
      • -
    • -

      -1.0: Function introduced. -

      +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Get the HTTP version
-
-
Version = cowboy_req:version(Req).
-
-
-
+
Version = cowboy_req:version(Req).
+

See also

-
-

cowboy_req(3)

-
- +

cowboy_req(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_req/index.html b/docs/en/cowboy/2.3/manual/cowboy_req/index.html index 3f577b0e..72291d4b 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_req/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_req/index.html @@ -62,414 +62,218 @@

cowboy_req(3)

-

Name

-
-

cowboy_req - HTTP request and response

-
-
-
+

cowboy_req - HTTP request and response

Description

-
-

The module cowboy_req provides functions to access, manipulate -and respond to requests.

-

There are four types of functions in this module. They can be -differentiated by their name and their return type:

-
- ---- - - - - - - - - - - - +

The module cowboy_req provides functions to access, manipulate and respond to requests.

+

There are four types of functions in this module. They can be differentiated by their name and their return type:

+
Type Name pattern Return type

access

no verb, parse_*, match_*

Value

+ + + + + + - - - - + + + - - - - + + + - - - - + + + - -
TypeName patternReturn type
accessno verb, parse_*, match_*Value

question

has_*

boolean()

questionhas_*boolean()

modification

set_*

Req

modificationset_*Req

action

any other verb

ok | {Result, Value, Req}

actionany other verbok | {Result, Value, Req}
-
-

Any Req returned must be used in place of the one passed as -argument. Functions that perform an action in particular write -state in the Req object to make sure you are using the function -correctly. For example, it’s only possible to send one response, -and to read the body once.

-
-
-
+ +

Any Req returned must be used in place of the one passed as argument. Functions that perform an action in particular write state in the Req object to make sure you are using the function correctly. For example, it's only possible to send one response, and to read the body once.

Exports

-
-

Connection:

-
-

Raw request:

-
-

Processed request:

-
-

Request body:

-
-

Response:

-
-
-
-
+

Connection:

+ +

Raw request:

+ +

Processed request:

+ +

Request body:

+ +

Response:

+

Types

-
-

push_opts()

-
-
-
push_opts() :: #{
-    method => binary(),            %% case sensitive
-    scheme => binary(),            %% lowercase; case insensitive
-    host   => binary(),            %% lowercase; case insensitive
-    port   => inet:port_number(),
-    qs     => binary()             %% case sensitive
-}
-

Push options.

-

By default, Cowboy will use the GET method, an empty query string, -and take the scheme, host and port directly from the current -request’s URI.

-
-
+
push_opts() :: #{
+    method => binary(),            %% case sensitive
+    scheme => binary(),            %% lowercase; case insensitive
+    host   => binary(),            %% lowercase; case insensitive
+    port   => inet:port_number(),
+    qs     => binary()             %% case sensitive
+}
+
+

Push options.

+

By default, Cowboy will use the GET method, an empty query string, and take the scheme, host and port directly from the current request's URI.

read_body_opts()

-
-
-
read_body_opts() :: #{
-    length  => non_neg_integer(),
-    period  => non_neg_integer(),
-    timeout => timeout()
-}
-

Body reading options.

-

The defaults are function-specific.

-
-
+
read_body_opts() :: #{
+    length  => non_neg_integer(),
+    period  => non_neg_integer(),
+    timeout => timeout()
+}
+
+

Body reading options.

+

The defaults are function-specific.

req()

-
-
-
req() :: #{
-    method  := binary(),               %% case sensitive
-    version := cowboy:http_version() | atom(),
-    scheme  := binary(),               %% lowercase; case insensitive
-    host    := binary(),               %% lowercase; case insensitive
-    port    := inet:port_number(),
-    path    := binary(),               %% case sensitive
-    qs      := binary(),               %% case sensitive
-    headers := cowboy:http_headers(),
-    peer    := {inet:ip_address(), inet:port_number()},
-    sock    := {inet:ip_address(), inet:port_number()},
-    cert    := binary() | undefined
-}
-

The Req object.

-

Contains information about the request and response. While -some fields are publicly documented, others aren’t and shouldn’t -be used.

-

You may add custom fields if required. Make sure to namespace -them by prepending an underscore and the name of your application:

-
-
Setting a custom field
-
-
Req#{_myapp_auth_method => pubkey}.
- -
+
Req#{_myapp_auth_method => pubkey}.
+

resp_body()

-
-
-
resp_body() :: iodata()
-    | {sendfile, Offset, Length, Filename}
+
resp_body() :: iodata()
+    | {sendfile, Offset, Length, Filename}
 
-Offset   :: non_neg_integer()
-Length   :: non_neg_integer()
-Filename :: file:name_all()
-

Response body.

-

It can take two forms: the actual data to be sent or a -tuple indicating which file to send.

-

When sending data directly, the type is either a binary or -an iolist. Iolists are an efficient way to build output. -Instead of concatenating strings or binaries, you can simply -build a list containing the fragments you want to send in the -order they should be sent:

-
-
Example iolists usage
-
-
1> RespBody = ["Hello ", [<<"world">>, $!]].
-["Hello ",[<<"world">>,33]]
-2> io:format("~s~n", [RespBody]).
-Hello world!
-

Note that the length must be greater than zero for any data -to be sent. Cowboy will send an empty body when the length -is zero.

- - - -
+
1> RespBody = ["Hello ", [<<"world">>, $!]].
+["Hello ",[<<"world">>,33]]
+2> io:format("~s~n", [RespBody]).
+Hello world!
+
+

Note that the length must be greater than zero for any data to be sent. Cowboy will send an empty body when the length is zero.

See also

-
-

cowboy(7)

-
- +

cowboy(7)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_rest/index.html b/docs/en/cowboy/2.3/manual/cowboy_rest/index.html index 6a8a9b34..f0fdfd09 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_rest/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_rest/index.html @@ -62,670 +62,475 @@

cowboy_rest(3)

-

Name

-
-

cowboy_rest - REST handlers

-
-
-
+

cowboy_rest - REST handlers

Description

-
-

The module cowboy_rest implements the HTTP state machine.

-

Implementing REST handlers is not enough to provide a REST -interface; this interface must also follow the REST -constraints including HATEOAS (hypermedia as the engine -of application state).

-
-
-
+

The module cowboy_rest implements the HTTP state machine.

+

Implementing REST handlers is not enough to provide a REST interface; this interface must also follow the REST constraints including HATEOAS (hypermedia as the engine of application state).

Callbacks

-
-

REST handlers implement the following interface:

-
-
-
init(Req, State)
-    -> {cowboy_rest, Req, State}
-
-Callback(Req, State)
-    -> {Result, Req, State}
-     | {stop, Req, State}
-     | {{switch_handler, Module}, Req, State}
-     | {{switch_handler, Module, Opts}, Req, State}
-
-terminate(Reason, Req, State) -> ok  %% optional
-
-Req    :: cowboy_req:req()
-State  :: any()
-Module :: module()
-Opts   :: any()
-Reason :: normal
-        | {crash, error | exit | throw, any()}
-
-Callback - see below
-Result   - see below
-Default  - see below
-

The init/2 callback is common to all handlers. To switch -to the REST handler behavior, it must return cowboy_rest -as the first element of the tuple.

-

The Callback/2 above represents all the REST-specific -callbacks. They are described in the following section -of this manual. REST-specific callbacks differ by their -name, semantics, result and default values. The default -value is the one used when the callback has not been -implemented. They otherwise all follow the same interface.

-

The stop tuple can be returned to stop REST processing. -If no response was sent before then, Cowboy will send a -204 No Content. The stop tuple can be returned from -any callback, excluding expires, generate_etag, -last_modified and variances.

-

A switch_handler tuple can be returned from these same -callbacks to stop REST processing and switch to a different -handler type. This is very useful to, for example, to stream -the response body.

-

The optional terminate/3 callback will ultimately be called -with the reason for the termination of the handler. -Cowboy will terminate the process right after this. There -is no need to perform any cleanup in this callback.

-

The following terminate reasons are defined for loop handlers:

-
-
-normal -
-
-

- The handler terminated normally. -

+

REST handlers implement the following interface:

+
+
init(Req, State)
+    -> {cowboy_rest, Req, State}
+
+Callback(Req, State)
+    -> {Result, Req, State}
+     | {stop, Req, State}
+     | {{switch_handler, Module}, Req, State}
+     | {{switch_handler, Module, Opts}, Req, State}
+
+terminate(Reason, Req, State) -> ok  %% optional
+
+Req    :: cowboy_req:req()
+State  :: any()
+Module :: module()
+Opts   :: any()
+Reason :: normal
+        | {crash, error | exit | throw, any()}
+
+Callback - see below
+Result   - see below
+Default  - see below
+
+

The init/2 callback is common to all handlers. To switch to the REST handler behavior, it must return cowboy_rest as the first element of the tuple.

+

The Callback/2 above represents all the REST-specific callbacks. They are described in the following section of this manual. REST-specific callbacks differ by their name, semantics, result and default values. The default value is the one used when the callback has not been implemented. They otherwise all follow the same interface.

+

The stop tuple can be returned to stop REST processing. If no response was sent before then, Cowboy will send a 204 No Content. The stop tuple can be returned from any callback, excluding expires, generate_etag, last_modified and variances.

+

A switch_handler tuple can be returned from these same callbacks to stop REST processing and switch to a different handler type. This is very useful to, for example, to stream the response body.

+

The optional terminate/3 callback will ultimately be called with the reason for the termination of the handler. Cowboy will terminate the process right after this. There is no need to perform any cleanup in this callback.

+

The following terminate reasons are defined for loop handlers:

+
normal
+

The handler terminated normally.

-
-{crash, Class, Reason} -
-
-

- A crash occurred in the handler. Class and Reason can be - used to obtain more information about the crash. The function - erlang:get_stacktrace/0 can also be called to obtain the - stacktrace of the process when the crash occurred. -

+
{crash, Class, Reason}
+

A crash occurred in the handler. Class and Reason can be used to obtain more information about the crash. The function erlang:get_stacktrace/0 can also be called to obtain the stacktrace of the process when the crash occurred.

-
-
-
-
+

REST callbacks

-
-

AcceptCallback

-
-
-
AcceptCallback(Req, State) -> {Result, Req, State}
-
-Result  :: true | {true, URI :: iodata()} | false}
-Default  - crash
-

Process the request body.

-

This function should create or update the resource using the -request body.

-

For PUT requests, the body is a representation of the resource -that is being created or replaced.

-

For POST requests, the body is typically application-specific -instructions on how to process the request, but it may also -be a representation of the resource. When creating a new -resource with POST at a different location, return {true, URI} -with URI the new location.

-

For PATCH requests, the body is a series of instructions on -how to update the resource. Patch files or JSON Patch are -examples of such media types.

-

A response body may be sent. The appropriate media type, charset -and language for the response can be retrieved from the Req -object using the media_type, charset and language keys, -respectively. The body can be set using -cowboy_req:set_resp_body(3).

-
-
+
+
AcceptCallback(Req, State) -> {Result, Req, State}
+
+Result  :: true | {true, URI :: iodata()} | false}
+Default  - crash
+
+

Process the request body.

+

This function should create or update the resource using the request body.

+

For PUT requests, the body is a representation of the resource that is being created or replaced.

+

For POST requests, the body is typically application-specific instructions on how to process the request, but it may also be a representation of the resource. When creating a new resource with POST at a different location, return {true, URI} with URI the new location.

+

For PATCH requests, the body is a series of instructions on how to update the resource. Patch files or JSON Patch are examples of such media types.

+

A response body may be sent. The appropriate media type, charset and language for the response can be retrieved from the Req object using the media_type, charset and language keys, respectively. The body can be set using cowboy_req:set_resp_body(3).

allowed_methods

-
-
-
allowed_methods(Req, State) -> {Result, Req, State}
+
allowed_methods(Req, State) -> {Result, Req, State}
 
-Result  :: [binary()]  %% case sensitive
-Default :: [<<"GET">>, <<"HEAD">>, <<"OPTIONS">>]
-

Return the list of allowed methods.

-
-
+Result :: [binary()] %% case sensitive +Default :: [<<"GET">>, <<"HEAD">>, <<"OPTIONS">>] +
+

Return the list of allowed methods.

allow_missing_post

-
-
-
allow_missing_post(Req, State) -> {Result, Req, State}
+
allow_missing_post(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: true
-

Return whether POST is allowed when the resource doesn’t exist.

-

Returning true here means that a new resource will be -created. The URI for the newly created resource should be -returned from the AcceptCallback function.

-
-
+Result :: boolean() +Default :: true +
+

Return whether POST is allowed when the resource doesn't exist.

+

Returning true here means that a new resource will be created. The URI for the newly created resource should be returned from the AcceptCallback function.

charsets_provided

-
-
-
charsets_provided(Req, State) -> {Result, Req, State}
+
charsets_provided(Req, State) -> {Result, Req, State}
 
-Result  :: [binary()]  %% lowercase; case insensitive
-Default  - skip this step
-

Return the list of charsets the resource provides in order -of preference.

-

During content negotiation Cowboy will pick the most -appropriate charset for the client. The client advertises -charsets it prefers with the accept-charset header. When -that header is missing, Cowboy picks the first charset -from the resource.

-

Cowboy will add the negotiated charset to the Req object -after this step completes:

-
-
+

Cowboy will add the negotiated charset to the Req object after this step completes:

+
-
req() :: #{
-    charset => binary()  %% lowercase; case insensitive
-}
-
-
+
req() :: #{
+    charset => binary()  %% lowercase; case insensitive
+}
+

content_types_accepted

-
-
-
content_types_accepted(Req, State) -> {Result, Req, State}
-
-Result     :: [{binary() | ParsedMime, AcceptCallback :: atom()}]
-ParsedMime :: {Type :: binary(), SubType :: binary(), '*' | Params}
-Params     :: [{Key :: binary(), Value :: binary()}]
-
-Default     - crash
-

Return the list of media types the resource accepts in -order of preference.

-

A media type is made of different parts. The media type -text/html;charset=utf-8 is of type text, subtype html -and has a single parameter charset with value utf-8.

-

Cowboy will match the content-type request header against -the media types the server accepts and select the appropriate -callback. When that header is missing, or when the server does not -accept this media type, the request fails and an error response -is returned. Cowboy will execute the callback immediately otherwise.

-

An empty parameters list [] means that no parameters will be -accepted. When any parameter is acceptable, the tuple form -should be used with parameters as the atom '*'.

-

Cowboy treats all parameters as case sensitive, except for the -charset parameter, which is known to be case insensitive. You -should therefore always provide the charset as a lowercase -binary string.

- -
+
+
content_types_accepted(Req, State) -> {Result, Req, State}
+
+Result     :: [{binary() | ParsedMime, AcceptCallback :: atom()}]
+ParsedMime :: {Type :: binary(), SubType :: binary(), '*' | Params}
+Params     :: [{Key :: binary(), Value :: binary()}]
+
+Default     - crash
+
+ +

Return the list of media types the resource accepts in order of preference.

+

A media type is made of different parts. The media type text/html;charset=utf-8 is of type text, subtype html and has a single parameter charset with value utf-8.

+ + + +

Cowboy will match the content-type request header against the media types the server accepts and select the appropriate callback. When that header is missing, or when the server does not accept this media type, the request fails and an error response is returned. Cowboy will execute the callback immediately otherwise.

+ +

An empty parameters list [] means that no parameters will be accepted. When any parameter is acceptable, the tuple form should be used with parameters as the atom '*'.

+

Cowboy treats all parameters as case sensitive, except for the charset parameter, which is known to be case insensitive. You should therefore always provide the charset as a lowercase binary string.

+ + + + + +

content_types_provided

-
-
-
content_types_provided(Req, State) -> {Result, Req, State}
-
-Result     :: [{binary() | ParsedMime, ProvideCallback :: atom()}]
-ParsedMime :: {Type :: binary(), SubType :: binary(), '*' | Params}
-Params     :: [{Key :: binary(), Value :: binary()}]
-
-Default     - [{{ <<"text">>, <<"html">>, '*'}, to_html}]
-

Return the list of media types the resource provides in -order of preference.

-

A media type is made of different parts. The media type -text/html;charset=utf-8 is of type text, subtype html -and has a single parameter charset with value utf-8.

-

During content negotiation Cowboy will pick the most appropriate -media type for the client. The client advertises media types it -prefers with the accept header. When that header is missing, -the content negotiation fails and an error response is returned.

-

The callback given for the selected media type will be called -at the end of the execution of GET and HEAD requests when a -representation must be sent to the client.

-

An empty parameters list [] means that no parameters will be -accepted. When any parameter is acceptable, the tuple form -should be used with parameters as the atom '*'.

-

Cowboy treats all parameters as case sensitive, except for the -charset parameter, which is known to be case insensitive. You -should therefore always provide the charset as a lowercase -binary string.

-

Cowboy will add the negotiated media_type to the Req object -after this step completes:

-
-
-
req() :: #{
-    media_type => ParsedMime
-}
-
-
+
+
content_types_provided(Req, State) -> {Result, Req, State}
+
+Result     :: [{binary() | ParsedMime, ProvideCallback :: atom()}]
+ParsedMime :: {Type :: binary(), SubType :: binary(), '*' | Params}
+Params     :: [{Key :: binary(), Value :: binary()}]
+
+Default     - [{{ <<"text">>, <<"html">>, '*'}, to_html}]
+
+ + +

Return the list of media types the resource provides in order of preference.

+

A media type is made of different parts. The media type text/html;charset=utf-8 is of type text, subtype html and has a single parameter charset with value utf-8.

+ + + +

During content negotiation Cowboy will pick the most appropriate media type for the client. The client advertises media types it prefers with the accept header. When that header is missing, the content negotiation fails and an error response is returned.

+

The callback given for the selected media type will be called at the end of the execution of GET and HEAD requests when a representation must be sent to the client.

+ +

An empty parameters list [] means that no parameters will be accepted. When any parameter is acceptable, the tuple form should be used with parameters as the atom '*'.

+

Cowboy treats all parameters as case sensitive, except for the charset parameter, which is known to be case insensitive. You should therefore always provide the charset as a lowercase binary string.

+

Cowboy will add the negotiated media_type to the Req object after this step completes:

+
+
req() :: #{
+    media_type => ParsedMime
+}
+
+

delete_completed

-
-
-
delete_completed(Req, State) -> {Result, Req, State}
+
delete_completed(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: true
-

Return whether the resource has been fully deleted from the -system, including from any internal cache.

-

Returning false will result in a 202 Accepted response -being sent instead of a 200 OK or 204 No Content.

-
-
+Result :: boolean() +Default :: true +
+

Return whether the resource has been fully deleted from the system, including from any internal cache.

+

Returning false will result in a 202 Accepted response being sent instead of a 200 OK or 204 No Content.

delete_resource

-
-
-
delete_resource(Req, State) -> {Result, Req, State}
+
delete_resource(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: false
-

Delete the resource.

-

Cowboy will send an error response when this function -returns false.

- -
+Result :: boolean() +Default :: false +
+

Delete the resource.

+

Cowboy will send an error response when this function returns false.

expires

-
-
-
expires(Req, State) -> {Result, Req, State}
+
expires(Req, State) -> {Result, Req, State}
 
-Result  :: calendar:datetime() | binary() | undefined
-Default :: undefined
-

Return the resource’s expiration date.

- -
+Result :: calendar:datetime() | binary() | undefined +Default :: undefined +
+

Return the resource's expiration date.

forbidden

-
-
-
forbidden(Req, State) -> {Result, Req, State}
+
forbidden(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: false
-

Return whether access to the resource is forbidden.

-

A 403 Forbidden response will be sent if this -function returns true. This status code means that -access is forbidden regardless of authentication, -and that the request shouldn’t be repeated.

- -
+Result :: boolean() +Default :: false +
+

Return whether access to the resource is forbidden.

+

A 403 Forbidden response will be sent if this function returns true. This status code means that access is forbidden regardless of authentication, and that the request shouldn't be repeated.

generate_etag

-
-
-
generate_etag(Req, State) -> {Result, Req, State}
+
generate_etag(Req, State) -> {Result, Req, State}
 
-Result  :: binary() | {weak | strong, binary()}
-Default  - no etag value
-

Return the entity tag of the resource.

-

When a binary is returned, the value is automatically -parsed to a tuple. The binary must be in the same -format as the etag header, including quotes.

- -
+Result :: binary() | {weak | strong, binary()} +Default - no etag value +
+

Return the entity tag of the resource.

+

When a binary is returned, the value is automatically parsed to a tuple. The binary must be in the same format as the etag header, including quotes.

is_authorized

-
-
-
is_authorized(Req, State) -> {Result, Req, State}
+
is_authorized(Req, State) -> {Result, Req, State}
 
-Result  :: true | {false, AuthHeader :: iodata()}
-Default  - true
-

Return whether the user is authorized to perform the action.

-

This function should be used to perform any necessary -authentication of the user before attempting to perform -any action on the resource.

-

When authentication fails, the AuthHeader value will -be sent in the www-authenticate header for the -401 Unauthorized response.

- -
+Result :: true | {false, AuthHeader :: iodata()} +Default - true +
+

Return whether the user is authorized to perform the action.

+

This function should be used to perform any necessary authentication of the user before attempting to perform any action on the resource.

+

When authentication fails, the AuthHeader value will be sent in the www-authenticate header for the 401 Unauthorized response.

is_conflict

-
-
-
is_conflict(Req, State) -> {Result, Req, State}
+
is_conflict(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: false
-

Return whether the PUT request results in a conflict.

-

A 409 Conflict response is sent when true.

- -
+Result :: boolean() +Default :: false +
+

Return whether the PUT request results in a conflict.

+

A 409 Conflict response is sent when true.

known_methods

-
-
-
known_methods(Req, State) -> {Result, Req, State}
+
known_methods(Req, State) -> {Result, Req, State}
 
-Result  :: [binary()]  %% case sensitive
-Default :: [<<"GET">>, <<"HEAD">>, <<"POST">>, <<"PUT">>,
-            <<"PATCH">>, <<"DELETE">>, <<"OPTIONS">>]
-

Return the list of known methods.

-

The full list of methods known by the server should be -returned, regardless of their use in the resource.

-

The default value lists the methods Cowboy knows and -implement in cowboy_rest.

- -
+Result :: [binary()] %% case sensitive +Default :: [<<"GET">>, <<"HEAD">>, <<"POST">>, <<"PUT">>, + <<"PATCH">>, <<"DELETE">>, <<"OPTIONS">>] +
+

Return the list of known methods.

+

The full list of methods known by the server should be returned, regardless of their use in the resource.

+

The default value lists the methods Cowboy knows and implement in cowboy_rest.

languages_provided

-
-
-
languages_provided(Req, State) -> {Result, Req, State}
+
languages_provided(Req, State) -> {Result, Req, State}
 
-Result  :: [binary()]  %% lowercase; case insensitive
-Default  - skip this step
-

Return the list of languages the resource provides in order -of preference.

-

During content negotiation Cowboy will pick the most -appropriate language for the client. The client advertises -languages it prefers with the accept-language header. When -that header is missing, Cowboy picks the first language -from the resource.

-

Cowboy will add the negotiated language to the Req object -after this step completes:

-
-
+

Cowboy will add the negotiated language to the Req object after this step completes:

+
-
req() :: #{
-    language => binary()  %% lowercase; case insensitive
-}
-
-
+
req() :: #{
+    language => binary()  %% lowercase; case insensitive
+}
+

last_modified

-
-
-
last_modified(Req, State) -> {Result, Req, State}
+
last_modified(Req, State) -> {Result, Req, State}
 
-Result  :: calendar:datetime()
-Default  - no last modified value
-

Return the resource’s last modification date.

-

This date will be used to test against the if-modified-since -and if-unmodified-since headers, and sent as the last-modified -header in the response to GET and HEAD requests.

- -
+Result :: calendar:datetime() +Default - no last modified value +
+

Return the resource's last modification date.

+

This date will be used to test against the if-modified-since and if-unmodified-since headers, and sent as the last-modified header in the response to GET and HEAD requests.

malformed_request

-
-
-
malformed_request(Req, State) -> {Result, Req, State}
+
malformed_request(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: false
-

Return whether the request is malformed.

-

A request is malformed when a component required by the -resource is invalid. This may include the query string -or individual headers. They should be parsed and validated -in this function. The body should not be read at this point.

- -
+Result :: boolean() +Default :: false +
+

Return whether the request is malformed.

+

A request is malformed when a component required by the resource is invalid. This may include the query string or individual headers. They should be parsed and validated in this function. The body should not be read at this point.

moved_permanently

-
-
-
moved_permanently(Req, State) -> {Result, Req, State}
+
moved_permanently(Req, State) -> {Result, Req, State}
 
-Result  :: {true, URI :: iodata()} | false
-Default :: false
-

Return whether the resource was permanently moved, and -what its new location is.

- -
+Result :: {true, URI :: iodata()} | false +Default :: false +
+

Return whether the resource was permanently moved, and what its new location is.

moved_temporarily

-
-
-
moved_temporarily(Req, State) -> {Result, Req, State}
+
moved_temporarily(Req, State) -> {Result, Req, State}
 
-Result  :: {true, URI :: iodata()} | false
-Default :: false
-

Return whether the resource was temporarily moved, and -what its new location is.

- -
+Result :: {true, URI :: iodata()} | false +Default :: false +
+

Return whether the resource was temporarily moved, and what its new location is.

multiple_choices

-
-
-
multiple_choices(Req, State) -> {Result, Req, State}
-
-Result  :: boolean()
-Default :: false
-

Return whether the client should engage in reactive -negotiation.

-

Return true when the server has multiple representations -of a resource, each with their specific identifier, but is -unable to determine which is best for the client. For -example an image might have different sizes and the server -is unable to determine the capabilities of the client.

-

When returning true the server should send a body with -links to the different representations. If the server has -a preferred representation it can send its link inside a -location header.

- -
+
+
multiple_choices(Req, State) -> {Result, Req, State}
+
+Result  :: boolean()
+Default :: false
+
+

Return whether the client should engage in reactive negotiation.

+

Return true when the server has multiple representations of a resource, each with their specific identifier, but is unable to determine which is best for the client. For example an image might have different sizes and the server is unable to determine the capabilities of the client.

+

When returning true the server should send a body with links to the different representations. If the server has a preferred representation it can send its link inside a location header.

options

-
-
-
options(Req, State) -> {ok, Req, State}
-

Respond to an OPTIONS request.

-

The response should inform the client the communication -options available for this resource. By default Cowboy -will send a 200 OK response with the allow header set.

-
-
+
options(Req, State) -> {ok, Req, State}
+
+

Respond to an OPTIONS request.

+

The response should inform the client the communication options available for this resource. By default Cowboy will send a 200 OK response with the allow header set.

previously_existed

-
-
-
previously_existed(Req, State) -> {Result, Req, State}
+
previously_existed(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: false
-

Return whether the resource existed previously.

- -
+Result :: boolean() +Default :: false +
+

Return whether the resource existed previously.

ProvideCallback

-
-
-
ProvideCallback(Req, State) -> {Result, Req, State}
+
ProvideCallback(Req, State) -> {Result, Req, State}
 
-Result  :: cowboy_req:resp_body()
-Default  - crash
-

Return the response body.

-

The response body can be provided either as the actual data -to be sent or a tuple indicating which file to send.

-

This function is called for both GET and HEAD requests. For -the latter the body is not sent, however.

-

Note that there used to be a way to stream the response body. -It was temporarily removed and will be added back in a later -release.

- -
+Result :: cowboy_req:resp_body() +Default - crash +
+

Return the response body.

+

The response body can be provided either as the actual data to be sent or a tuple indicating which file to send.

+

This function is called for both GET and HEAD requests. For the latter the body is not sent, however.

+ + + +

Note that there used to be a way to stream the response body. It was temporarily removed and will be added back in a later release.

+

resource_exists

-
-
-
resource_exists(Req, State) -> {Result, Req, State}
+
resource_exists(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: true
-

Return whether the resource exists.

- -
+Result :: boolean() +Default :: true +
+

Return whether the resource exists.

service_available

-
-
-
service_available(Req, State) -> {Result, Req, State}
+
service_available(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: true
-

Return whether the service is available.

-

A 503 Service Unavailable response will be sent when this -function returns false.

- -
+Result :: boolean() +Default :: true +
+

Return whether the service is available.

+

A 503 Service Unavailable response will be sent when this function returns false.

uri_too_long

-
-
-
uri_too_long(Req, State) -> {Result, Req, State}
+
uri_too_long(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: false
-

Return whether the requested URI is too long.

-

This function can be used to further restrict the length -of the URI for this specific resource.

- -
+Result :: boolean() +Default :: false +
+

Return whether the requested URI is too long.

+

This function can be used to further restrict the length of the URI for this specific resource.

valid_content_headers

-
-
-
valid_content_headers(Req, State) -> {Result, Req, State}
+
valid_content_headers(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: true
-

Return whether the content headers are valid.

-

This callback can be used to reject requests that have -invalid content header values, for example an unsupported -content-encoding.

- -
+Result :: boolean() +Default :: true +
+

Return whether the content headers are valid.

+

This callback can be used to reject requests that have invalid content header values, for example an unsupported content-encoding.

valid_entity_length

-
-
-
valid_entity_length(Req, State) -> {Result, Req, State}
+
valid_entity_length(Req, State) -> {Result, Req, State}
 
-Result  :: boolean()
-Default :: true
-

Return whether the request body length is within acceptable boundaries.

-

A 413 Request Entity Too Large response will be sent if this -function returns false.

- -
+Result :: boolean() +Default :: true +
+

Return whether the request body length is within acceptable boundaries.

+

A 413 Request Entity Too Large response will be sent if this function returns false.

variances

-
-
-
variances(Req, State) -> {Result, Req, State}
+
variances(Req, State) -> {Result, Req, State}
 
-Result  :: [binary()]  %% case insensitive
-Default :: []
-

Return the list of request headers that affect the -representation of the resource.

-

Cowboy automatically adds the accept, accept-charset and -accept-language headers when necessary. It’s also useful -to note that some standard headers also do not need to be -listed here, like the authorization header.

- - - -
+Result :: [binary()] %% case insensitive +Default :: [] +
+

Return the list of request headers that affect the representation of the resource.

+

Cowboy automatically adds the accept, accept-charset and accept-language headers when necessary. It's also useful to note that some standard headers also do not need to be listed here, like the authorization header.

Changelog

-
-
    -
  • -

    -2.1: The switch_handler return value was added. -

    +
    • 2.1: The switch_handler return value was added.
      • -
    • -

      -1.0: Behavior introduced. -

      +
    • 1.0: Behavior introduced.
      • -
-
- -
+

See also

-
-

cowboy(7), -cowboy_handler(3)

-
-
+

cowboy(7), cowboy_handler(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_router.compile/index.html b/docs/en/cowboy/2.3/manual/cowboy_router.compile/index.html index 1904d026..eb6bb8c8 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_router.compile/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_router.compile/index.html @@ -62,87 +62,48 @@

cowboy_router:compile(3)

-

Name

-
-

cowboy_router:compile - Compile routes to the resources

-
-
-
+

cowboy_router:compile - Compile routes to the resources

Description

-
-
-
-
compile(cowboy_router:routes()) -> cowboy_router:dispatch_rules()
-

Compile routes to the resources.

-

Takes a human readable list of routes and transforms it -into a form more efficient to process.

-
-
-
+
compile(cowboy_router:routes()) -> cowboy_router:dispatch_rules()
+
+

Compile routes to the resources.

+

Takes a human readable list of routes and transforms it into a form more efficient to process.

Arguments

-
-
-
-Routes -
-
-

-Human readable list of routes. -

+
Routes
+

Human readable list of routes.

-
-
- -
+

Return value

-
-

An opaque dispatch rules value is returned. This value -must be given to Cowboy as a middleware environment value.

-
-
-
+

An opaque dispatch rules value is returned. This value must be given to Cowboy as a middleware environment value.

Changelog

-
-
    -
  • -

    -1.0: Function introduced. -

    +
    • 1.0: Function introduced.
      • -
-
-
-
+

Examples

-
-
-
Compile routes and start a listener
-
-
Dispatch = cowboy_router:compile([
-    {'_', [
-        {"/", toppage_h, []},
-        {"/[...], cowboy_static, {priv_dir, my_example_app, ""}}
-    ]}
-]),
-
-{ok, _} = cowboy:start_clear(example, [{port, 8080}], #{
-    env => #{dispatch => Dispatch}
-}).
-
-
-
+
Dispatch = cowboy_router:compile([
+    {'_', [
+        {"/", toppage_h, []},
+        {"/[...], cowboy_static, {priv_dir, my_example_app, ""}}
+    ]}
+]),
+
+{ok, _} = cowboy:start_clear(example, [{port, 8080}], #{
+    env => #{dispatch => Dispatch}
+}).
+

See also

-
-

cowboy_router(3)

-
- +

cowboy_router(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_router/index.html b/docs/en/cowboy/2.3/manual/cowboy_router/index.html index dae2a362..a5895995 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_router/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_router/index.html @@ -62,110 +62,65 @@

cowboy_router(3)

-

Name

-
-

cowboy_router - Router middleware

-
-
-
+

cowboy_router - Router middleware

Description

-
-

The cowboy_router middleware maps the requested host and -path to the handler to be used for processing the request.

-

The router takes the dispatch rules as input from the -middleware environment. Dispatch rules are generated by -calling the -cowboy_router:compile(3) -function.

-

When a route matches, the router sets the handler and -handler_opts middleware environment values containing -the handler module and initial state, respectively.

-

The router will stop execution when no route matches. -It will send a 400 response if no host was found, and -a 404 response otherwise.

-
-
-
+

The cowboy_router middleware maps the requested host and path to the handler to be used for processing the request.

+

The router takes the dispatch rules as input from the middleware environment. Dispatch rules are generated by calling the cowboy_router:compile(3) function.

+

When a route matches, the router sets the handler and handler_opts middleware environment values containing the handler module and initial state, respectively.

+

The router will stop execution when no route matches. It will send a 400 response if no host was found, and a 404 response otherwise.

Exports

-
-
-
-
-
+

Types

-
-

bindings()

-
-
-
bindings() :: #{atom() => any()}
-

Bindings found during routing.

-
-
+
bindings() :: #{atom() => any()}
+
+

Bindings found during routing.

dispatch_rules()

-

Opaque type containing the compiled routes.

-
-
+

Opaque type containing the compiled routes.

routes()

-
-
-
routes() = [
-    {Host, PathList} |
-    {Host, Fields, PathList}
+
routes() = [
+    {Host, PathList} |
+    {Host, Fields, PathList}
 ]
 
-PathList :: [
-    {Path, Handler, InitialState} |
-    {Path, Fields, Handler, InitialState}
+PathList :: [
+    {Path, Handler, InitialState} |
+    {Path, Fields, Handler, InitialState}
 ]
 
-Host         :: '_' | iodata()
-Path         :: '_' | iodata()
-Fields       :: cowboy:fields()
-Handler      :: module()
-InitialState :: any()
-

Human readable list of routes to handlers.

-

Cowboy uses this list to map hosts and paths, optionally -augmented with constraints applied to the bindings, to -handler modules.

-

The syntax for routes is currently defined in the user guide.

-
-
+Host :: '_' | iodata() +Path :: '_' | iodata() +Fields :: cowboy:fields() +Handler :: module() +InitialState :: any() +
+

Human readable list of routes to handlers.

+

Cowboy uses this list to map hosts and paths, optionally augmented with constraints applied to the bindings, to handler modules.

+

The syntax for routes is currently defined in the user guide.

+ +

tokens()

-
-
-
tokens() :: [binary()]
-

List of host_info and path_info tokens that were found -using the ... syntax.

- - - -
+
tokens() :: [binary()]
+
+

List of host_info and path_info tokens that were found using the ... syntax.

See also

-
-

cowboy(7), -cowboy_req:binding(3), -cowboy_req:bindings(3), -cowboy_req:host_info(3), -cowboy_req:path_info(3)

-
- +

cowboy(7), cowboy_req:binding(3), cowboy_req:bindings(3), cowboy_req:host_info(3), cowboy_req:path_info(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_static/index.html b/docs/en/cowboy/2.3/manual/cowboy_static/index.html index 9cb78a3d..b00701d7 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_static/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_static/index.html @@ -62,175 +62,110 @@

cowboy_static(3)

-

Name

-
-

cowboy_static - Static file handler

-
-
-
+

cowboy_static - Static file handler

Description

-
-

The module cowboy_static implements file serving capabilities -using the REST semantics provided by cowboy_rest.

-

The static file handler is a pre-written handler coming with -Cowboy. To serve files, use it in your routes.

-
-
-
+

The module cowboy_static implements file serving capabilities using the REST semantics provided by cowboy_rest.

+

The static file handler is a pre-written handler coming with Cowboy. To serve files, use it in your routes.

Options

-
-
-
-
opts() :: {priv_file, App, Path}
-        | {priv_file, App, Path, Extra}
-        | {file, Path}
-        | {file, Path, Extra}
-        | {priv_dir, App, Path}
-        | {priv_dir, App, Path, Extra}
-        | {dir, Path}
-        | {dir, Path, Extra}
-
-App        :: atom()
-Path       :: binary() | string()
-Extra      :: [Etag | Mimetypes]
-
-Etag       :: {etag, module(), function()}
-            | {etag, false}
-
-Mimetypes  :: {mimetypes, module(), function()}
-            | {mimetypes, binary() | ParsedMime}
-
-ParsedMime :: {Type :: binary(), SubType :: binary(), Params}
-Params     :: [{Key :: binary(), Value :: binary()}]
-

Static handler configuration.

-
-
-priv_file -
-
-

-Send a file. -

-

The path is relative to the given application’s private -directory.

+
opts() :: {priv_file, App, Path}
+        | {priv_file, App, Path, Extra}
+        | {file, Path}
+        | {file, Path, Extra}
+        | {priv_dir, App, Path}
+        | {priv_dir, App, Path, Extra}
+        | {dir, Path}
+        | {dir, Path, Extra}
+
+App        :: atom()
+Path       :: binary() | string()
+Extra      :: [Etag | Mimetypes]
+
+Etag       :: {etag, module(), function()}
+            | {etag, false}
+
+Mimetypes  :: {mimetypes, module(), function()}
+            | {mimetypes, binary() | ParsedMime}
+
+ParsedMime :: {Type :: binary(), SubType :: binary(), Params}
+Params     :: [{Key :: binary(), Value :: binary()}]
+
+

Static handler configuration.

+
priv_file
+

Send a file.

+

The path is relative to the given application's private directory.

-
-file -
-
-

-Send a file. -

-

The path is either absolute or relative to the Erlang node’s -current directory.

+
file
+

Send a file.

+

The path is either absolute or relative to the Erlang node's current directory.

-
-priv_dir -
-
-

-Recursively serve files from a directory. -

-

The path is relative to the given application’s private -directory.

+
priv_dir
+

Recursively serve files from a directory.

+

The path is relative to the given application's private directory.

-
-dir -
-
-

-Recursively serve files from a directory. -

-

The path is either absolute or relative to the Erlang node’s -current directory.

+
dir
+

Recursively serve files from a directory.

+

The path is either absolute or relative to the Erlang node's current directory.

-
-

The extra options allow you to define how the etag should be -calculated and how the MIME type of files should be detected.

-

By default the static handler will generate an etag based -on the size and modification time of the file. You may disable -the etag entirely with {etag, false} or provide a module -and function that will be called when needed:

-
-
-
generate_etag(Path, Size, Mtime) -> {strong | weak, binary()}
-
-Path  :: binary()
-Size  :: non_neg_integer()
-Mtime :: file:date_time()
-

By default the static handler will detect Web-related MIME types -by looking at the file extension. You can provide a specific -MIME type that will always be used, or a module and function that -will be called when needed:

-
-
-
detect_mimetype(Path) -> ParsedMime
-
-Path       :: binary()
-ParsedMime :: {Type :: binary(), SubType :: binary(), Params}
-Params     :: [{Key :: binary(), Value :: binary()}]
-

Cowboy comes with two such functions; the default function -cow_mimetypes:web/1, and a second function generated from -the Apache mime.types file, cow_mimetypes:all/1.

-

The MIME type function should return -{<<"application">>, <<"octet-stream">>, []} -when it fails to detect a file’s MIME type.

- - -
+
detect_mimetype(Path) -> ParsedMime
+
+Path       :: binary()
+ParsedMime :: {Type :: binary(), SubType :: binary(), Params}
+Params     :: [{Key :: binary(), Value :: binary()}]
+
+ +

Cowboy comes with two such functions; the default function cow_mimetypes:web/1, and a second function generated from the Apache mime.types file, cow_mimetypes:all/1.

+

The MIME type function should return {<<"application">>, <<"octet-stream">>, []} when it fails to detect a file's MIME type.

Changelog

-
-
    -
  • -

    -1.0: Handler introduced. -

    +
    • 1.0: Handler introduced.
      • -
-
- -
+

Examples

-
-
-
Custom etag function
-
-
generate_etag(Path, Size, Mtime) ->
-    {strong, integer_to_binary(
-        erlang:phash2({Path, Size, Mtime}, 16#ffffffff))}.
-
-
Custom MIME type function
-
-
always_octet_stream(_Path) ->
-    case filename:extension(Path) of
-        <<".erl">> -> {<<"text">>, <<"plain">>, []};
-        _ -> {<<"application">>, <<"octet-stream">>, []}
-    end.
-
-
-
+
always_octet_stream(_Path) ->
+    case filename:extension(Path) of
+        <<".erl">> -> {<<"text">>, <<"plain">>, []};
+        _ -> {<<"application">>, <<"octet-stream">>, []}
+    end.
+

See also

-
-

cowboy(7), -cowboy_router(3)

-
- +

cowboy(7), cowboy_router(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_stream/index.html b/docs/en/cowboy/2.3/manual/cowboy_stream/index.html index 3755a025..298fc18e 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_stream/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_stream/index.html @@ -62,452 +62,307 @@

cowboy_stream(3)

-

Name

-
-

cowboy_handler - Stream handlers

-
-
-
+

cowboy_handler - Stream handlers

Description

-
-

The module cowboy_stream defines a callback interface -and a protocol for handling HTTP streams.

-

An HTTP request and its associated response is called -a stream. A connection may have many streams. In HTTP/1.1 -they are executed sequentially, while in HTTP/2 they are -executed concurrently.

-

Cowboy calls the stream handler for nearly all events -related to a stream. Exceptions vary depending on the -protocol.

-

Extra care must be taken when implementing stream handlers -to ensure compatibility. While some modification of the -events and commands is allowed, it is generally not a good -idea to completely omit them.

-
-
-
+

The module cowboy_stream defines a callback interface and a protocol for handling HTTP streams.

+

An HTTP request and its associated response is called a stream. A connection may have many streams. In HTTP/1.1 they are executed sequentially, while in HTTP/2 they are executed concurrently.

+

Cowboy calls the stream handler for nearly all events related to a stream. Exceptions vary depending on the protocol.

+

Extra care must be taken when implementing stream handlers to ensure compatibility. While some modification of the events and commands is allowed, it is generally not a good idea to completely omit them.

Callbacks

-
-

Stream handlers must implement the following interface:

-
-
-
init(StreamID, Req, Opts) -> {Commands, State}
-data(StreamID, IsFin, Data, State) -> {Commands, State}
-info(StreamID, Info, State) -> {Commands, State}
-terminate(StreamID, Reason, State) -> any()
-early_error(StreamID, Reason, PartialReq, Resp, Opts) -> Resp
-
-StreamID   :: cowboy_stream:streamid()
-Req        :: cowboy_req:req()
-Opts       :: cowboy:opts()
-Commands   :: cowboy_stream:commands()
-State      :: any()
-IsFin      :: cowboy_stream:fin()
-Data       :: binary()
-Info       :: any()
-Reason     :: cowboy_stream:reason()
-PartialReq  - cowboy_req:req(), except all fields are optional
-Resp       :: cowboy_stream:resp_command()
-

HTTP/1.1 will initialize a stream only when the request-line -and all headers have been received. When errors occur before -that point Cowboy will call the callback early_error/5 -with a partial request, the error reason and the response -Cowboy intends to send. All other events go throuh the -stream handler using the normal callbacks.

-

HTTP/2 will initialize the stream when the HEADERS block has -been fully received and decoded. Any protocol error occuring -before that will not result in a response being sent and -will therefore not go through the stream handler. In addition -Cowboy may terminate streams without sending an HTTP response -back.

-

The stream is initialized by calling init/3. All streams -that are initialized will eventually be terminated by calling -terminate/3.

-

When Cowboy receives data for the stream it will call data/4. -The data given is the request body after any transfer decoding -has been applied.

-

When Cowboy receives a message addressed to a stream, or when -Cowboy needs to inform the stream handler that an internal -event has occurred, it will call info/3.

-
-
-
+
init(StreamID, Req, Opts) -> {Commands, State}
+data(StreamID, IsFin, Data, State) -> {Commands, State}
+info(StreamID, Info, State) -> {Commands, State}
+terminate(StreamID, Reason, State) -> any()
+early_error(StreamID, Reason, PartialReq, Resp, Opts) -> Resp
+
+StreamID   :: cowboy_stream:streamid()
+Req        :: cowboy_req:req()
+Opts       :: cowboy:opts()
+Commands   :: cowboy_stream:commands()
+State      :: any()
+IsFin      :: cowboy_stream:fin()
+Data       :: binary()
+Info       :: any()
+Reason     :: cowboy_stream:reason()
+PartialReq  - cowboy_req:req(), except all fields are optional
+Resp       :: cowboy_stream:resp_command()
+
+

HTTP/1.1 will initialize a stream only when the request-line and all headers have been received. When errors occur before that point Cowboy will call the callback early_error/5 with a partial request, the error reason and the response Cowboy intends to send. All other events go throuh the stream handler using the normal callbacks.

+

HTTP/2 will initialize the stream when the HEADERS block has been fully received and decoded. Any protocol error occuring before that will not result in a response being sent and will therefore not go through the stream handler. In addition Cowboy may terminate streams without sending an HTTP response back.

+

The stream is initialized by calling init/3. All streams that are initialized will eventually be terminated by calling terminate/3.

+

When Cowboy receives data for the stream it will call data/4. The data given is the request body after any transfer decoding has been applied.

+

When Cowboy receives a message addressed to a stream, or when Cowboy needs to inform the stream handler that an internal event has occurred, it will call info/3.

Commands

-
-

Stream handlers can return a list of commands to be executed -from the init/3, data/4 and info/3 callbacks. In addition, -the early_error/5 callback must return a response command.

-

The following commands are defined:

-
+

Stream handlers can return a list of commands to be executed from the init/3, data/4 and info/3 callbacks. In addition, the early_error/5 callback must return a response command.

+ + + + + +

The following commands are defined:

inform

-

Send an informational response to the client.

-
-
-
{inform, cowboy:http_status(), cowboy:http_headers()}
-

Any number of informational responses may be sent, -but only until the final response is sent.

-
-
+
{inform, cowboy:http_status(), cowboy:http_headers()}
+
+

Any number of informational responses may be sent, but only until the final response is sent.

response

-

Send a response to the client.

-
-
-
{response, cowboy:http_status(), cowboy:http_headers(),
-    cowboy_req:resp_body()}
-

No more data can be sent after this command.

- -
+
{response, cowboy:http_status(), cowboy:http_headers(),
+    cowboy_req:resp_body()}
+
+

No more data can be sent after this command.

headers

-

Initiate a response to the client.

-
-
-
{headers, cowboy:http_status(), cowboy:http_headers()}
-

This initiates a response to the client. The stream -will end when a data command with the fin flag or -a trailer command is returned.

- -
+
{headers, cowboy:http_status(), cowboy:http_headers()}
+
+

This initiates a response to the client. The stream will end when a data command with the fin flag or a trailer command is returned.

data

-

Send data to the client.

-
-
-
{data, fin(), iodata()}
- -
+
{data, fin(), iodata()}
+

trailers

-

Send response trailers to the client.

-
-
-
{trailers, cowboy:http_headers()}
- -
+
{trailers, cowboy:http_headers()}
+

push

-

Push a resource to the client.

-
-
-
{push, Method, Scheme, Host, inet:port_number(),
-    Path, Qs, cowboy:http_headers()}
+
{push, Method, Scheme, Host, inet:port_number(),
+    Path, Qs, cowboy:http_headers()}
 
-Method = Scheme = Host = Path = Qs = binary()
-

The command will be ignored if the protocol does not provide -any server push mechanism.

- -
+Method = Scheme = Host = Path = Qs = binary() +
+

The command will be ignored if the protocol does not provide any server push mechanism.

flow

-
-
-
{flow, pos_integer()}
-

Request more data to be read from the request body. The -exact behavior depends on the protocol.

- -
+
{flow, pos_integer()}
+
+

Request more data to be read from the request body. The exact behavior depends on the protocol.

spawn

-

Inform Cowboy that a process was spawned and should be -supervised.

-
-
-
{spawn, pid(), timeout()}
- -
+
{spawn, pid(), timeout()}
+

error_response

-

Send an error response if no response was sent previously.

-
-
-
{error_response, cowboy:http_status(), cowboy:http_headers(), iodata()}
- -
+
{error_response, cowboy:http_status(), cowboy:http_headers(), iodata()}
+

switch_protocol

-

Switch to a different protocol.

-
-
-
{switch_protocol, cowboy:http_headers(), module(), state()}
-

Contains the headers that will be sent in the 101 response, -along with the module implementing the protocol we are -switching to and its initial state.

- -
+
{switch_protocol, cowboy:http_headers(), module(), state()}
+
+

Contains the headers that will be sent in the 101 response, along with the module implementing the protocol we are switching to and its initial state.

stop

-

Stop the stream.

-
-
-
stop
-

While no more data can be sent after the fin flag was set, -the stream is still tracked by Cowboy until it is stopped by -the handler.

-

The behavior when stopping a stream for which no response -has been sent will vary depending on the protocol. The stream -will end successfully as far as the client is concerned.

-

To indicate that an error occurred, either use error_response -before stopping, or use internal_error.

- -
+
stop
+
+

While no more data can be sent after the fin flag was set, the stream is still tracked by Cowboy until it is stopped by the handler.

+

The behavior when stopping a stream for which no response has been sent will vary depending on the protocol. The stream will end successfully as far as the client is concerned.

+

To indicate that an error occurred, either use error_response before stopping, or use internal_error.

internal_error

-

Stop the stream with an error.

-
-
-
{internal_error, Reason, HumanReadable}
-
-Reason        = any()
-HumanReadable = atom()
-

This command should be used when the stream cannot continue -because of an internal error. An error_response command -may be sent before that to advertise to the client why the -stream is dropped.

- - - -
+
{internal_error, Reason, HumanReadable}
+
+Reason        = any()
+HumanReadable = atom()
+
+

This command should be used when the stream cannot continue because of an internal error. An error_response command may be sent before that to advertise to the client why the stream is dropped.

Predefined events

-
-

Cowboy will forward all messages sent to the stream to -the info/3 callback. To send a message to a stream, -send a message to the connection process with the form -{{Pid, StreamID}, Msg}. The connection process will -then forward Msg to the stream handlers.

-

Cowboy will also forward the exit signals for the -processes that the stream spawned.

-
+

Cowboy will forward all messages sent to the stream to the info/3 callback. To send a message to a stream, send a message to the connection process with the form {{Pid, StreamID}, Msg}. The connection process will then forward Msg to the stream handlers.

+

Cowboy will also forward the exit signals for the processes that the stream spawned.

EXIT

-

A process spawned by this stream has exited.

-
-
+ + +

A process spawned by this stream has exited.

+
-
{'EXIT', pid(), any()}
-

This is the raw exit message without any modification.

-
-
+
{'EXIT', pid(), any()}
+
+

This is the raw exit message without any modification.

+ + + + + + + + + + + + + + + + +

inform

-

Same as the inform command.

-

Sent when the request process reads the body and an -expect: 100-continue header was present in the request, -or when the request process sends an informational -response on its own.

-
-
+

Same as the inform command.

+

Sent when the request process reads the body and an expect: 100-continue header was present in the request, or when the request process sends an informational response on its own.

response

-

Same as the response command.

-

Usually sent when the request process replies to the client. -May also be sent by Cowboy internally.

-
-
+

Same as the response command.

+

Usually sent when the request process replies to the client. May also be sent by Cowboy internally.

headers

-

Same as the headers command.

-

Sent when the request process starts replying to the client.

-
-
+

Same as the headers command.

+

Sent when the request process starts replying to the client.

data

-

Same as the data command.

-

Sent when the request process streams data to the client.

-
-
+

Same as the data command.

+

Sent when the request process streams data to the client.

trailers

-

Same as the trailers command.

-

Sent when the request process sends the trailer field values -to the client.

-
-
+

Same as the trailers command.

+

Sent when the request process sends the trailer field values to the client.

push

-

Same as the push command.

-

Sent when the request process pushes a resource to the client.

-
-
+

Same as the push command.

+

Sent when the request process pushes a resource to the client.

switch_protocol

-

Same as the switch_protocol command.

-

Sent when switching to the HTTP/2 or Websocket protocol.

-
-
- -
+

Same as the switch_protocol command.

+ +

Sent when switching to the HTTP/2 or Websocket protocol.

Exports

-
-

The following function should be called by modules implementing -stream handlers to execute the next stream handler in the list:

-
-
-
-
+

Types

-
-

commands()

-
-
-
commands() :: [Command]
-

See the list of commands for details.

-
-
+
commands() :: [Command]
+
+

See the list of commands for details.

fin()

-
-
-
fin() :: fin | nofin
-

Used in commands and events to indicate that this is -the end of the stream.

-
-
+
fin() :: fin | nofin
+
+

Used in commands and events to indicate that this is the end of the stream.

partial_req()

-
-
-
req() :: #{
-    method  => binary(),               %% case sensitive
-    version => cowboy:http_version() | atom(),
-    scheme  => binary(),               %% lowercase; case insensitive
-    host    => binary(),               %% lowercase; case insensitive
-    port    => inet:port_number(),
-    path    => binary(),               %% case sensitive
-    qs      => binary(),               %% case sensitive
-    headers => cowboy:http_headers(),
-    peer    => {inet:ip_address(), inet:port_number()}
-}
-

Partial request information received when an early error is -detected.

- -
+
req() :: #{
+    method  => binary(),               %% case sensitive
+    version => cowboy:http_version() | atom(),
+    scheme  => binary(),               %% lowercase; case insensitive
+    host    => binary(),               %% lowercase; case insensitive
+    port    => inet:port_number(),
+    path    => binary(),               %% case sensitive
+    qs      => binary(),               %% case sensitive
+    headers => cowboy:http_headers(),
+    peer    => {inet:ip_address(), inet:port_number()}
+}
+
+

Partial request information received when an early error is detected.

reason()

-
-
-
reason() :: normal | switch_protocol
-    | {internal_error, timeout | {error | exit | throw, any()}, HumanReadable}
-    | {socket_error, closed | atom(), HumanReadable}
-    | {stream_error, Error, HumanReadable}
-    | {connection_error, Error, HumanReadable}
-    | {stop, cow_http2:frame(), HumanReadable}
-
-Error         = atom()
-HumanReadable = atom()
-

Reason for the stream termination.

- -
+
reason() :: normal | switch_protocol
+    | {internal_error, timeout | {error | exit | throw, any()}, HumanReadable}
+    | {socket_error, closed | atom(), HumanReadable}
+    | {stream_error, Error, HumanReadable}
+    | {connection_error, Error, HumanReadable}
+    | {stop, cow_http2:frame(), HumanReadable}
+
+Error         = atom()
+HumanReadable = atom()
+
+

Reason for the stream termination.

resp_command()

-
-
-
resp_command() :: {response, cowboy:http_status(),
-    cowboy:http_headers(), cowboy_req:resp_body()}
-

See the response command for details.

- -
+
resp_command() :: {response, cowboy:http_status(),
+    cowboy:http_headers(), cowboy_req:resp_body()}
+
+

See the response command for details.

streamid()

-
-
-
streamid() :: any()
-

The identifier for this stream.

-

The identifier is unique over the connection process. -It is possible to form a unique identifier node-wide and -cluster-wide by wrapping it in a {self(), StreamID} -tuple.

- - - -
+
streamid() :: any()
+
+

The identifier for this stream.

+

The identifier is unique over the connection process. It is possible to form a unique identifier node-wide and cluster-wide by wrapping it in a {self(), StreamID} tuple.

Changelog

-
-
    -
  • -

    -2.2: The trailers command was introduced. -

    +
    • 2.2: The trailers command was introduced.
      • -
    • -

      -2.0: Module introduced. -

      +
    • 2.0: Module introduced.
      • -
-
- -
+

See also

-
-

cowboy(7), -cowboy_http(3), -cowboy_http2(3)

-
-
+

cowboy(7), cowboy_http(3), cowboy_http2(3)

+ diff --git a/docs/en/cowboy/2.3/manual/cowboy_websocket/index.html b/docs/en/cowboy/2.3/manual/cowboy_websocket/index.html index 697423aa..7cd153bd 100644 --- a/docs/en/cowboy/2.3/manual/cowboy_websocket/index.html +++ b/docs/en/cowboy/2.3/manual/cowboy_websocket/index.html @@ -62,308 +62,148 @@

cowboy_websocket(3)

-

Name

-
-

cowboy_websocket - Websocket

-
-
-
+

cowboy_websocket - Websocket

Description

-
-

The module cowboy_websocket implements Websocket -as a Ranch protocol. It also defines a callback interface -for handling Websocket connections.

-
-
-
+

The module cowboy_websocket implements Websocket as a Ranch protocol. It also defines a callback interface for handling Websocket connections.

Callbacks

-
-

Websocket handlers must implement the following callback -interface:

-
-
-
init(Req, State)
-    -> {cowboy_websocket, Req, State}
-     | {cowboy_websocket, Req, State, Opts}
-
-websocket_init(State)            -> CallResult  %% optional
-websocket_handle(InFrame, State) -> CallResult
-websocket_info(Info, State)      -> CallResult
-
-terminate(Reason, PartialReq, State) -> ok      %% optional
-
-Req        :: cowboy_req:req()
-PartialReq :: map()
-State      :: any()
-Opts       :: cowboy_websocket:opts()
-InFrame    :: {text | binary | ping | pong, binary()}
-OutFrame   :: cow_ws:frame()                    %% see types below
-Info       :: any()
-
-CallResult :: {ok, State}
-            | {ok, State, hibernate}
-            | {reply, OutFrame | [OutFrame], State}
-            | {reply, OutFrame | [OutFrame], State, hibernate}
-            | {stop, State}
-
-Reason     :: normal | stop | timeout
-            | remote | {remote, cow_ws:close_code(), binary()}
-            | {error, badencoding | badframe | closed | atom()}
-            | {crash, error | exit | throw, any()}
-

The init/2 callback is common to all handlers. To upgrade -the connection to Websocket, it must return cowboy_websocket -as the first element of the tuple.

-

Any operation requiring the HTTP request must be done in the -init/2 function, as the Req object will not be available -after it returns. Websocket sub-protocol selection should -therefore be done in this function.

-

The optional websocket_init/1 callback will be called once -the connection has been upgraded to Websocket. It can be used -to perform any required initialization of the handler.

-

Note that the init/2 function does not run in the same -process as the Websocket callbacks. Any Websocket-specific -initialization must be done in websocket_init/1.

-

The websocket_handle/2 callback will be called for every -frame received. The websocket_info/2 callback will be -called for every Erlang message received.

-

All three Websocket callbacks may send one or more frames -back to the client (by returning a reply tuple) or terminate -the connection (by sending a close frame or returning a stop -tuple).

-

The optional terminate/3 callback will ultimately be called -with the reason for the termination of the connection. This -callback is common to all handlers. Note that Websocket will -not provide the full Req object by default, to save memory.

-

Cowboy will terminate the process right after closing the -Websocket connection. This means that there is no need to -perform any cleanup in the terminate/3 callback.

-

The following terminate reasons are defined for Websocket -connections:

-
-
-normal -
-
-

- The connection was closed normally before establishing a Websocket - connection. This typically happens if an ok tuple is returned - from the init/2 callback. -

+
init(Req, State)
+    -> {cowboy_websocket, Req, State}
+     | {cowboy_websocket, Req, State, Opts}
+
+websocket_init(State)            -> CallResult  %% optional
+websocket_handle(InFrame, State) -> CallResult
+websocket_info(Info, State)      -> CallResult
+
+terminate(Reason, PartialReq, State) -> ok      %% optional
+
+Req        :: cowboy_req:req()
+PartialReq :: map()
+State      :: any()
+Opts       :: cowboy_websocket:opts()
+InFrame    :: {text | binary | ping | pong, binary()}
+OutFrame   :: cow_ws:frame()                    %% see types below
+Info       :: any()
+
+CallResult :: {ok, State}
+            | {ok, State, hibernate}
+            | {reply, OutFrame | [OutFrame], State}
+            | {reply, OutFrame | [OutFrame], State, hibernate}
+            | {stop, State}
+
+Reason     :: normal | stop | timeout
+            | remote | {remote, cow_ws:close_code(), binary()}
+            | {error, badencoding | badframe | closed | atom()}
+            | {crash, error | exit | throw, any()}
+
+

The init/2 callback is common to all handlers. To upgrade the connection to Websocket, it must return cowboy_websocket as the first element of the tuple.

+

Any operation requiring the HTTP request must be done in the init/2 function, as the Req object will not be available after it returns. Websocket sub-protocol selection should therefore be done in this function.

+

The optional websocket_init/1 callback will be called once the connection has been upgraded to Websocket. It can be used to perform any required initialization of the handler.

+

Note that the init/2 function does not run in the same process as the Websocket callbacks. Any Websocket-specific initialization must be done in websocket_init/1.

+

The websocket_handle/2 callback will be called for every frame received. The websocket_info/2 callback will be called for every Erlang message received.

+

All three Websocket callbacks may send one or more frames back to the client (by returning a reply tuple) or terminate the connection (by sending a close frame or returning a stop tuple).

+

The optional terminate/3 callback will ultimately be called with the reason for the termination of the connection. This callback is common to all handlers. Note that Websocket will not provide the full Req object by default, to save memory.

+

Cowboy will terminate the process right after closing the Websocket connection. This means that there is no need to perform any cleanup in the terminate/3 callback.

+

The following terminate reasons are defined for Websocket connections:

+
normal
+

The connection was closed normally before establishing a Websocket connection. This typically happens if an ok tuple is returned from the init/2 callback.

-
-remote -
-
-

- The remote endpoint closed the connection without giving any - further details. -

+
remote
+

The remote endpoint closed the connection without giving any further details.

-
-{remote, Code, Payload} -
-
-

- The remote endpoint closed the connection with the given - Code and Payload as the reason. -

+
{remote, Code, Payload}
+

The remote endpoint closed the connection with the given Code and Payload as the reason.

-
-stop -
-
-

- The handler requested to close the connection, either by returning - a stop tuple or by sending a close frame. -

+
stop
+

The handler requested to close the connection, either by returning a stop tuple or by sending a close frame.

-
-timeout -
-
-

- The connection has been closed due to inactivity. The timeout - value can be configured from init/2. -

+
timeout
+

The connection has been closed due to inactivity. The timeout value can be configured from init/2.

-
-{crash, Class, Reason} -
-
-

- A crash occurred in the handler. Class and Reason can be - used to obtain more information about the crash. The function - erlang:get_stacktrace/0 can also be called to obtain the - stacktrace of the process when the crash occurred. -

+
{crash, Class, Reason}
+

A crash occurred in the handler. Class and Reason can be used to obtain more information about the crash. The function erlang:get_stacktrace/0 can also be called to obtain the stacktrace of the process when the crash occurred.

-
-{error, badencoding} -
-
-

- A text frame was sent by the client with invalid encoding. All - text frames must be valid UTF-8. -

+
{error, badencoding}
+

A text frame was sent by the client with invalid encoding. All text frames must be valid UTF-8.

-
-{error, badframe} -
-
-

- A protocol error has been detected. -

+
{error, badframe}
+

A protocol error has been detected.

-
-{error, closed} -
-
-

- The socket has been closed brutally without a close frame being - received first. -

+
{error, closed}
+

The socket has been closed brutally without a close frame being received first.

-
-{error, Reason} -
-
-

- A socket error ocurred. -

+
{error, Reason}
+

A socket error ocurred.

-
- - -
+

Types

-
-

cow_ws:frame()

-
-
-
frame() :: {text, iodata()}
-    | {binary, iodata()}
-    | ping | {ping, iodata()}
-    | pong | {pong, iodata()}
-    | close | {close, iodata()} | {close, close_code(), iodata()}
-
-close_code() :: 1000..1003 | 1006..1011 | 3000..4999
-

Websocket frames that can be sent as a response.

-

Note that there is no need to send pong frames back as -Cowboy does it automatically for you.

-
-
+
frame() :: {text, iodata()}
+    | {binary, iodata()}
+    | ping | {ping, iodata()}
+    | pong | {pong, iodata()}
+    | close | {close, iodata()} | {close, close_code(), iodata()}
+
+close_code() :: 1000..1003 | 1006..1011 | 3000..4999
+
+

Websocket frames that can be sent as a response.

+

Note that there is no need to send pong frames back as Cowboy does it automatically for you.

opts()

-
-
-
opts() :: #{
-    compress => boolean(),
-    idle_timeout => timeout(),
-    max_frame_size => non_neg_integer() | infinity,
-    req_filter => fun((cowboy_req:req()) -> map())
-}
-

Websocket handler options.

-

This configuration is passed to Cowboy from the init/2 -function:

-
-
-
init(Req, State) ->
-    Opts = #{compress => true},
-    {cowboy_websocket, Req, State, Opts}.
-

The default value is given next to the option name:

-
-
-compress (false) -
-
-

- Whether to enable the Websocket frame compression - extension. Frames will only be compressed for the - clients that support this extension. -

+
init(Req, State) ->
+    Opts = #{compress => true},
+    {cowboy_websocket, Req, State, Opts}.
+
+

The default value is given next to the option name:

+
compress (false)
+

Whether to enable the Websocket frame compression extension. Frames will only be compressed for the clients that support this extension.

-
-idle_timeout (60000) -
-
-

- Time in milliseconds that Cowboy will keep the - connection open without receiving anything from - the client. -

+
idle_timeout (60000)
+

Time in milliseconds that Cowboy will keep the connection open without receiving anything from the client.

-
-max_frame_size (infinity) -
-
-

- Maximum frame size allowed by this Websocket - handler. Cowboy will close the connection when - a client attempts to send a frame that goes over - this limit. For fragmented frames this applies - to the size of the reconstituted frame. -

+
max_frame_size (infinity)
+

Maximum frame size allowed by this Websocket handler. Cowboy will close the connection when a client attempts to send a frame that goes over this limit. For fragmented frames this applies to the size of the reconstituted frame.

-
-req_filter -
-
-

- A function applied to the Req to compact it and - only keep required information. The Req is only - given back in the terminate/3 callback. By default - it keeps the method, version, URI components and peer - information. -

+
req_filter
+

A function applied to the Req to compact it and only keep required information. The Req is only given back in the terminate/3 callback. By default it keeps the method, version, URI components and peer information.

-
- - - -
+

Changelog

-
-
    -
  • -

    -2.0: The Req object is no longer passed to Websocket callbacks. -

    +
    • 2.0: The Req object is no longer passed to Websocket callbacks.
      • -
    • -

      -2.0: The callback websocket_terminate/3 was removed in favor of terminate/3. -

      +
    • 2.0: The callback websocket_terminate/3 was removed in favor of terminate/3.
      • -
    • -

      -1.0: Protocol introduced. -

      +
    • 1.0: Protocol introduced.
      • -
-
-
-
+

See also

-
-

cowboy(7), -cowboy_handler(3), -cowboy_http(3), -cowboy_http2(3)

-
-
+

cowboy(7), cowboy_handler(3), cowboy_http(3), cowboy_http2(3)

+ diff --git a/docs/en/cowboy/2.3/manual/http_status_codes/index.html b/docs/en/cowboy/2.3/manual/http_status_codes/index.html index 29aeb53f..77a7be98 100644 --- a/docs/en/cowboy/2.3/manual/http_status_codes/index.html +++ b/docs/en/cowboy/2.3/manual/http_status_codes/index.html @@ -62,271 +62,92 @@

HTTP status codes(7)

-

Name

-
-

HTTP status codes - status codes used by Cowboy

-
-
-
+

HTTP status codes - status codes used by Cowboy

Description

-
-

This chapter aims to list all HTTP status codes that Cowboy -may return, with details on the reasons why. The list given -here only includes the replies that Cowboy sends, not user -replies.

-
-
-
+

This chapter aims to list all HTTP status codes that Cowboy may return, with details on the reasons why. The list given here only includes the replies that Cowboy sends, not user replies.

100 Continue

-
-

When the client sends an expect: 100-continue header, -Cowboy automatically sends a this status code before -trying to read the request body. This behavior can be -disabled using the appropriate body option.

-
-
-
+

When the client sends an expect: 100-continue header, Cowboy automatically sends a this status code before trying to read the request body. This behavior can be disabled using the appropriate body option.

101 Switching Protocols

-
-

This is the status code sent when switching to the -Websocket protocol.

-
-
-
+

This is the status code sent when switching to the Websocket protocol.

200 OK

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

201 Created

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

202 Accepted

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

204 No Content

-
-

This status code is sent when the processing of a request -ends without any reply having been sent. It may also be -sent by cowboy_rest under normal conditions.

-
-
-
+

This status code is sent when the processing of a request ends without any reply having been sent. It may also be sent by cowboy_rest under normal conditions.

300 Multiple Choices

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

301 Moved Permanently

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

303 See Other

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

304 Not Modified

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

307 Temporary Redirect

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

400 Bad Request

-
-

Cowboy will send this status code for any of the -following reasons:

-
    -
  • -

    -Too many empty lines were sent before the request. -

    +

    Cowboy will send this status code for any of the following reasons:

    +
    • Too many empty lines were sent before the request.
      • -
    • -

      -The request-line could not be parsed. -

      +
    • The request-line could not be parsed.
      • -
    • -

      -Too many headers were sent. -

      +
    • Too many headers were sent.
      • -
    • -

      -A header name was too long. -

      +
    • A header name was too long.
      • -
    • -

      -A header value was too long. -

      +
    • A header value was too long.
      • -
    • -

      -The host header was missing from an HTTP/1.1 request. -

      +
    • The host header was missing from an HTTP/1.1 request.
      • -
    • -

      -The host header could not be parsed. -

      +
    • The host header could not be parsed.
      • -
    • -

      -The requested host was not found. -

      +
    • The requested host was not found.
      • -
    • -

      -The requested path could not be parsed. -

      +
    • The requested path could not be parsed.
      • -
    • -

      -The accept header could not be parsed when using REST. -

      +
    • The accept header could not be parsed when using REST.
      • -
    • -

      -REST under normal conditions. -

      +
    • REST under normal conditions.
      • -
    • -

      -A Websocket upgrade failed. -

      +
    • A Websocket upgrade failed.
      • -
-
-
-
+

401 Unauthorized

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

403 Forbidden

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

404 Not Found

-
-

This status code is sent when the router successfully -resolved the host but didn’t find a matching path for -the request. It may also be sent by cowboy_rest under -normal conditions.

-
-
-
+

This status code is sent when the router successfully resolved the host but didn't find a matching path for the request. It may also be sent by cowboy_rest under normal conditions.

405 Method Not Allowed

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

406 Not Acceptable

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

408 Request Timeout

-
-

Cowboy will send this status code to the client if the -client started to send a request, indicated by the -request-line being received fully, but failed to send -all headers in a reasonable time.

-
-
-
+

Cowboy will send this status code to the client if the client started to send a request, indicated by the request-line being received fully, but failed to send all headers in a reasonable time.

409 Conflict

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

410 Gone

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

412 Precondition Failed

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

413 Request Entity Too Large

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

414 Request-URI Too Long

-
-

Cowboy will send this status code to the client if the -request-line is too long. It may also be sent by -cowboy_rest under normal conditions.

-
-
-
+

Cowboy will send this status code to the client if the request-line is too long. It may also be sent by cowboy_rest under normal conditions.

415 Unsupported Media Type

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

500 Internal Server Error

-
-

This status code is sent when a crash occurs in HTTP, loop -or REST handlers, or when an invalid return value is -returned. It may also be sent by cowboy_rest under -normal conditions.

-
-
-
+

This status code is sent when a crash occurs in HTTP, loop or REST handlers, or when an invalid return value is returned. It may also be sent by cowboy_rest under normal conditions.

501 Not Implemented

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

503 Service Unavailable

-
-

This status code is sent by cowboy_rest.

-
-
-
+

This status code is sent by cowboy_rest.

505 HTTP Version Not Supported

-
-

Cowboy only supports the versions 1.0 and 1.1 of HTTP. -In all other cases this status code is sent back to the -client and the connection is closed.

-
-
+

Cowboy only supports the versions 1.0 and 1.1 of HTTP. In all other cases this status code is sent back to the client and the connection is closed.

+ diff --git a/docs/en/cowboy/2.3/manual/index.html b/docs/en/cowboy/2.3/manual/index.html index bdd44991..29259ec0 100644 --- a/docs/en/cowboy/2.3/manual/index.html +++ b/docs/en/cowboy/2.3/manual/index.html @@ -62,171 +62,77 @@

Cowboy Function Reference

-

Name

-
-

cowboy - Small, fast, modern HTTP server for Erlang/OTP

-
-
-
+

cowboy - Small, fast, modern HTTP server for Erlang/OTP

Description

-
-

Cowboy is an HTTP server for Erlang/OTP with support for the -HTTP/1.1, HTTP/2 and Websocket protocols.

-

Cowboy aims to provide a complete HTTP stack. This includes -the implementation of the HTTP RFCs but also any directly -related standards, like Websocket or Server-Sent Events.

-
-
-
+

Cowboy is an HTTP server for Erlang/OTP with support for the HTTP/1.1, HTTP/2 and Websocket protocols.

+

Cowboy aims to provide a complete HTTP stack. This includes the implementation of the HTTP RFCs but also any directly related standards, like Websocket or Server-Sent Events.

Modules

-
-

Functions:

-
-

Protocols:

-
+

Protocols:

+
-

Handlers:

-
+

Handlers:

+
-

Behaviors:

-
+

Behaviors:

+
-

Middlewares:

-
+

Middlewares:

+
-
-
-
+ +

Dependencies

-
-
    -
  • -

    -ranch(7) - Socket acceptor pool for TCP protocols -

    +
    • ranch(7) - Socket acceptor pool for TCP protocols
      • -
    • -

      -cowlib(7) - Support library for manipulating Web protocols -

      +
    • cowlib(7) - Support library for manipulating Web protocols
      • -
    • -

      -ssl - Secure communication over sockets -

      +
    • ssl - Secure communication over sockets
      • -
    • -

      -crypto - Crypto functions -

      +
    • crypto - Crypto functions
      • -
-

All these applications must be started before the cowboy -application. To start Cowboy and all dependencies at once:

-
-
-
{ok, _} = application:ensure_all_started(cowboy).
-
-
-
+
{ok, _} = application:ensure_all_started(cowboy).
+

Environment

-
-

The cowboy application does not define any application -environment configuration parameters.

-
- -
+

The cowboy application does not define any application environment configuration parameters.

See also

-
-

ranch(7), -cowlib(7)

-
-
+

ranch(7), cowlib(7)

+ -- cgit v1.2.3