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author | Loïc Hoguin <[email protected]> | 2014-07-06 13:10:35 +0200 |
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committer | Loïc Hoguin <[email protected]> | 2014-07-06 13:10:35 +0200 |
commit | 078d686a0ac0aed212db97d73bd1e4a9387a4956 (patch) | |
tree | 6bbc6111fdbdfedd3bb351bf3b01c63fac0d7143 /guide/cookies.md | |
parent | 1a71a733c37df70c15ebfd28157b10915cd738d1 (diff) | |
download | cowboy-078d686a0ac0aed212db97d73bd1e4a9387a4956.tar.gz cowboy-078d686a0ac0aed212db97d73bd1e4a9387a4956.tar.bz2 cowboy-078d686a0ac0aed212db97d73bd1e4a9387a4956.zip |
Provide installable man pages
make docs: generate Markdown and man pages in doc/
make install-docs: install man pages to be usable directly
Docs are generated from the ezdoc files in doc/src/.
Diffstat (limited to 'guide/cookies.md')
-rw-r--r-- | guide/cookies.md | 140 |
1 files changed, 0 insertions, 140 deletions
diff --git a/guide/cookies.md b/guide/cookies.md deleted file mode 100644 index bfc8651..0000000 --- a/guide/cookies.md +++ /dev/null @@ -1,140 +0,0 @@ -Using cookies -============= - -Cookies are a mechanism allowing applications to maintain -state on top of the stateless HTTP protocol. - -Cowboy provides facilities for handling cookies. It is highly -recommended to use them instead of writing your own, as the -implementation of cookies can vary greatly between clients. - -Cookies are stored client-side and sent with every subsequent -request that matches the domain and path for which they were -stored, including requests for static files. For this reason -they can incur a cost which must be taken in consideration. - -Also consider that, regardless of the options used, cookies -are not to be trusted. They may be read and modified by any -program on the user's computer, but also by proxies. You -should always validate cookie values before using them. Do -not store any sensitive information in cookies either. - -When explicitly setting the domain, the cookie will be sent -for the domain and all subdomains from that domain. Otherwise -the current domain will be used. The same is true for the -path. - -When the server sets cookies, they will only be available -for requests that are sent after the client receives the -response. - -Cookies are sent in HTTP headers, therefore they must have -text values. It is your responsibility to encode any other -data type. Also note that cookie names are de facto case -sensitive. - -Cookies can be set for the client session (which generally -means until the browser is closed), or it can be set for -a number of seconds. Once it expires, or when the server -says the cookie must exist for up to 0 seconds, the cookie -is deleted by the client. To avoid this while the user -is browsing your site, you should set the cookie for -every request, essentially resetting the expiration time. - -Cookies can be restricted to secure channels. This typically -means that such a cookie will only be sent over HTTPS, -and that it will only be available by client-side scripts -that run from HTTPS webpages. - -Finally, cookies can be restricted to HTTP and HTTPS requests, -essentially disabling their access from client-side scripts. - -Setting cookies ---------------- - -By default, cookies you set are defined for the session. - -``` erlang -SessionID = generate_session_id(), -Req2 = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, [], Req). -``` - -You can also make them expire at a specific point in the -future. - -``` erlang -SessionID = generate_session_id(), -Req2 = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, [ - {max_age, 3600} -], Req). -``` - -You can delete cookies that have already been set. The value -is ignored. - -``` erlang -Req2 = cowboy_req:set_resp_cookie(<<"sessionid">>, <<>>, [ - {max_age, 0} -], Req). -``` - -You can restrict them to a specific domain and path. -For example, the following cookie will be set for the domain -`my.example.org` and all its subdomains, but only on the path -`/account` and all its subdirectories. - -``` erlang -Req2 = cowboy_req:set_resp_cookie(<<"inaccount">>, <<"1">>, [ - {domain, "my.example.org"}, - {path, "/account"} -], Req). -``` - -You can restrict the cookie to secure channels, typically HTTPS. - -``` erlang -SessionID = generate_session_id(), -Req2 = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, [ - {secure, true} -], Req). -``` - -You can restrict the cookie to client-server communication -only. Such a cookie will not be available to client-side scripts. - -``` erlang -SessionID = generate_session_id(), -Req2 = cowboy_req:set_resp_cookie(<<"sessionid">>, SessionID, [ - {http_only, true} -], Req). -``` - -Cookies may also be set client-side, for example using -Javascript. - -Reading cookies ---------------- - -As we said, the client sends cookies with every request. -But unlike the server, the client only sends the cookie -name and value. - -You can read the value of a cookie. - -``` erlang -{CookieVal, Req2} = cowboy_req:cookie(<<"lang">>, Req). -``` - -You can also get a default value returned when the cookie -isn't set. - -``` erlang -{CookieVal, Req2} = cowboy_req:cookie(<<"lang">>, Req, <<"fr">>). -``` - -And you can obtain all cookies at once as a list of -key/value tuples. - -``` erlang -{AllCookies, Req2} = cowboy_req:cookies(Req). -``` |