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-rw-r--r--src/cowboy_req.erl105
1 files changed, 62 insertions, 43 deletions
diff --git a/src/cowboy_req.erl b/src/cowboy_req.erl
index 07acbe5..7bc8ad6 100644
--- a/src/cowboy_req.erl
+++ b/src/cowboy_req.erl
@@ -15,10 +15,30 @@
%% @doc HTTP request manipulation API.
%%
-%% Almost all functions in this module return a new <em>Req</em> variable.
-%% It should always be used instead of the one used in your function call
-%% because it keeps the state of the request. It also allows Cowboy to do
-%% some lazy evaluation and cache results where possible.
+%% The functions in this module try to follow this pattern for their
+%% return types:
+%% <dl>
+%% <dt>access:</dt>
+%% <dd><em>{Value, Req}</em></dd>
+%% <dt>action:</dt>
+%% <dd><em>{Result, Req} | {Result, Value, Req} | {error, atom()}</em></dd>
+%% <dt>modification:</dt>
+%% <dd><em>Req</em></dd>
+%% <dt>question (<em>has_*</em> or <em>is_*</em>):</dt>
+%% <dd><em>boolean()</em></dd>
+%% </dl>
+%%
+%% Exceptions include <em>chunk/2</em> which always returns <em>'ok'</em>,
+%% <em>to_list/1</em> which returns a list of key/values,
+%% and <em>transport/1</em> which returns <em>{ok, Transport, Socket}</em>.
+%%
+%% Also note that all body reading functions perform actions, as Cowboy
+%% doesn't read the request body until they are called.
+%%
+%% Whenever <em>Req</em> is returned, it should always be kept in place of
+%% the one given as argument in your function call, because it keeps
+%% track of the request and response state. Doing so allows Cowboy to do
+%% some lazy evaluation and cache results when possible.
-module(cowboy_req).
%% Request API.
@@ -277,12 +297,12 @@ headers(Req) ->
%% returned is used as a return value.
%% @see parse_header/3
-spec parse_header(cowboy_http:header(), Req)
- -> {any(), Req} | {undefined, binary(), Req}
+ -> {ok, any(), Req} | {undefined, binary(), Req}
| {error, badarg} when Req::req().
parse_header(Name, Req=#http_req{p_headers=PHeaders}) ->
case lists:keyfind(Name, 1, PHeaders) of
false -> parse_header(Name, Req, parse_header_default(Name));
- {Name, Value} -> {Value, Req}
+ {Name, Value} -> {ok, Value, Req}
end.
%% @doc Default values for semantic header parsing.
@@ -295,7 +315,7 @@ parse_header_default(_Name) -> undefined.
%%
%% When the header is unknown, the value is returned directly without parsing.
-spec parse_header(cowboy_http:header(), Req, any())
- -> {any(), Req} | {undefined, binary(), Req}
+ -> {ok, any(), Req} | {undefined, binary(), Req}
| {error, badarg} when Req::req().
parse_header(Name, Req, Default) when Name =:= 'Accept' ->
parse_header(Name, Req, Default,
@@ -365,23 +385,15 @@ parse_header(Name, Req, Default) ->
{undefined, Value, Req2}.
parse_header(Name, Req=#http_req{p_headers=PHeaders}, Default, Fun) ->
- case lists:keyfind(Name, 1, PHeaders) of
- {Name, P} ->
- {P, Req};
- false ->
- parse_header_no_cache(Name, Req, Default, Fun)
- end.
-
-parse_header_no_cache(Name, Req=#http_req{p_headers=PHeaders}, Default, Fun) ->
case header(Name, Req) of
{undefined, Req2} ->
- {Default, Req2#http_req{p_headers=[{Name, Default}|PHeaders]}};
+ {ok, Default, Req2#http_req{p_headers=[{Name, Default}|PHeaders]}};
{Value, Req2} ->
case Fun(Value) of
{error, badarg} ->
{error, badarg};
P ->
- {P, Req2#http_req{p_headers=[{Name, P}|PHeaders]}}
+ {ok, P, Req2#http_req{p_headers=[{Name, P}|PHeaders]}}
end
end.
@@ -464,8 +476,11 @@ has_body(Req) ->
-spec body_length(Req) -> {undefined | non_neg_integer(), Req} when Req::req().
body_length(Req) ->
case lists:keymember('Transfer-Encoding', 1, Req#http_req.headers) of
- true -> {undefined, Req};
- false -> parse_header('Content-Length', Req, 0)
+ true ->
+ {undefined, Req};
+ false ->
+ {ok, Length, Req2} = parse_header('Content-Length', Req, 0),
+ {Length, Req2}
end.
%% @doc Initialize body streaming and set custom decoding functions.
@@ -505,21 +520,19 @@ init_stream(TransferDecode, TransferState, ContentDecode, Req) ->
stream_body(Req=#http_req{body_state=waiting,
version=Version, transport=Transport, socket=Socket}) ->
case parse_header(<<"Expect">>, Req) of
- {[<<"100-continue">>], Req1} ->
+ {ok, [<<"100-continue">>], Req1} ->
HTTPVer = cowboy_http:version_to_binary(Version),
Transport:send(Socket,
<< HTTPVer/binary, " ", (status(100))/binary, "\r\n\r\n" >>);
- {undefined, Req1} ->
- ok;
- {undefined, _, Req1} ->
+ {ok, undefined, Req1} ->
ok
end,
case parse_header('Transfer-Encoding', Req1) of
- {[<<"chunked">>], Req2} ->
+ {ok, [<<"chunked">>], Req2} ->
stream_body(Req2#http_req{body_state=
{stream, fun cowboy_http:te_chunked/2, {0, 0},
fun cowboy_http:ce_identity/1}});
- {[<<"identity">>], Req2} ->
+ {ok, [<<"identity">>], Req2} ->
{Length, Req3} = body_length(Req2),
case Length of
0 ->
@@ -635,11 +648,17 @@ skip_body(Req) ->
%% @doc Return the full body sent with the reqest, parsed as an
%% application/x-www-form-urlencoded string. Essentially a POST query string.
%% @todo We need an option to limit the size of the body for QS too.
--spec body_qs(Req) -> {list({binary(), binary() | true}), Req} when Req::req().
+-spec body_qs(Req)
+ -> {ok, [{binary(), binary() | true}], Req} | {error, atom()}
+ when Req::req().
body_qs(Req=#http_req{urldecode={URLDecFun, URLDecArg}}) ->
- {ok, Body, Req2} = body(Req),
- {cowboy_http:x_www_form_urlencoded(
- Body, fun(Bin) -> URLDecFun(Bin, URLDecArg) end), Req2}.
+ case body(Req) of
+ {ok, Body, Req2} ->
+ {ok, cowboy_http:x_www_form_urlencoded(
+ Body, fun(Bin) -> URLDecFun(Bin, URLDecArg) end), Req2};
+ {error, Reason} ->
+ {error, Reason}
+ end.
%% Multipart Request API.
@@ -653,13 +672,13 @@ body_qs(Req=#http_req{urldecode={URLDecFun, URLDecArg}}) ->
%% If the request Content-Type is not a multipart one, <em>{error, badarg}</em>
%% is returned.
-spec multipart_data(Req)
- -> {{headers, cowboy_http:headers()} | {body, binary()}
- | end_of_part | eof, Req} when Req::req().
+ -> {headers, cowboy_http:headers(), Req} | {body, binary(), Req}
+ | {end_of_part | eof, Req} when Req::req().
multipart_data(Req=#http_req{body_state=waiting}) ->
- {{<<"multipart">>, _SubType, Params}, Req2} =
+ {ok, {<<"multipart">>, _SubType, Params}, Req2} =
parse_header('Content-Type', Req),
{_, Boundary} = lists:keyfind(<<"boundary">>, 1, Params),
- {Length, Req3} = parse_header('Content-Length', Req2),
+ {ok, Length, Req3} = parse_header('Content-Length', Req2),
multipart_data(Req3, Length, {more, cowboy_multipart:parser(Boundary)});
multipart_data(Req=#http_req{multipart={Length, Cont}}) ->
multipart_data(Req, Length, Cont());
@@ -668,9 +687,9 @@ multipart_data(Req=#http_req{body_state=done}) ->
%% @todo Typespecs.
multipart_data(Req, Length, {headers, Headers, Cont}) ->
- {{headers, Headers}, Req#http_req{multipart={Length, Cont}}};
+ {headers, Headers, Req#http_req{multipart={Length, Cont}}};
multipart_data(Req, Length, {body, Data, Cont}) ->
- {{body, Data}, Req#http_req{multipart={Length, Cont}}};
+ {body, Data, Req#http_req{multipart={Length, Cont}}};
multipart_data(Req, Length, {end_of_part, Cont}) ->
{end_of_part, Req#http_req{multipart={Length, Cont}}};
multipart_data(Req, 0, eof) ->
@@ -697,33 +716,33 @@ multipart_skip(Req) ->
case multipart_data(Req) of
{end_of_part, Req2} -> {ok, Req2};
{eof, Req2} -> {ok, Req2};
- {_Other, Req2} -> multipart_skip(Req2)
+ {_, _, Req2} -> multipart_skip(Req2)
end.
%% Response API.
%% @doc Add a cookie header to the response.
-spec set_resp_cookie(binary(), binary(),
- [cowboy_cookies:cookie_option()], Req) -> {ok, Req} when Req::req().
+ [cowboy_cookies:cookie_option()], Req) -> Req when Req::req().
set_resp_cookie(Name, Value, Options, Req) ->
{HeaderName, HeaderValue} = cowboy_cookies:cookie(Name, Value, Options),
set_resp_header(HeaderName, HeaderValue, Req).
%% @doc Add a header to the response.
-spec set_resp_header(cowboy_http:header(), iodata(), Req)
- -> {ok, Req} when Req::req().
+ -> Req when Req::req().
set_resp_header(Name, Value, Req=#http_req{resp_headers=RespHeaders}) ->
NameBin = header_to_binary(Name),
- {ok, Req#http_req{resp_headers=[{NameBin, Value}|RespHeaders]}}.
+ Req#http_req{resp_headers=[{NameBin, Value}|RespHeaders]}.
%% @doc Add a body to the response.
%%
%% The body set here is ignored if the response is later sent using
%% anything other than reply/2 or reply/3. The response body is expected
%% to be a binary or an iolist.
--spec set_resp_body(iodata(), Req) -> {ok, Req} when Req::req().
+-spec set_resp_body(iodata(), Req) -> Req when Req::req().
set_resp_body(Body, Req) ->
- {ok, Req#http_req{resp_body=Body}}.
+ Req#http_req{resp_body=Body}.
%% @doc Add a body function to the response.
%%
@@ -740,9 +759,9 @@ set_resp_body(Body, Req) ->
%%
%% @see cowboy_req:transport/1.
-spec set_resp_body_fun(non_neg_integer(),
- fun(() -> {sent, non_neg_integer()}), Req) -> {ok, Req} when Req::req().
+ fun(() -> {sent, non_neg_integer()}), Req) -> Req when Req::req().
set_resp_body_fun(StreamLen, StreamFun, Req) ->
- {ok, Req#http_req{resp_body={StreamLen, StreamFun}}}.
+ Req#http_req{resp_body={StreamLen, StreamFun}}.
%% @doc Return whether the given header has been set for the response.
-spec has_resp_header(cowboy_http:header(), req()) -> boolean().
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-10 18:16:02 +0000