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diff --git a/docs/en/cowboy/2.0/manual/cowboy_handler/index.html b/docs/en/cowboy/2.0/manual/cowboy_handler/index.html new file mode 100644 index 00000000..5954d21f --- /dev/null +++ b/docs/en/cowboy/2.0/manual/cowboy_handler/index.html @@ -0,0 +1,365 @@ +<!DOCTYPE html> +<html lang="en"> + +<head> + <meta charset="utf-8"> + <meta name="viewport" content="width=device-width, initial-scale=1.0"> + <meta name="description" content=""> + <meta name="author" content="Loïc Hoguin based on a design from (Soft10) Pol Cámara"> + + <meta name="generator" content="Hugo 0.15" /> + + <title>Nine Nines: cowboy_handler(3)</title> + + <link href='http://fonts.googleapis.com/css?family=Open+Sans:400,700,400italic' rel='stylesheet' type='text/css'> + + <link href="/css/bootstrap.min.css" rel="stylesheet"> + <link href="/css/99s.css" rel="stylesheet"> + + <link rel="shortcut icon" href="/img/ico/favicon.ico"> + <link rel="apple-touch-icon-precomposed" sizes="114x114" href="/img/ico/apple-touch-icon-114.png"> + <link rel="apple-touch-icon-precomposed" sizes="72x72" href="/img/ico/apple-touch-icon-72.png"> + <link rel="apple-touch-icon-precomposed" href="/img/ico/apple-touch-icon-57.png"> + + +</head> + + +<body class=""> + <header id="page-head"> + <div id="topbar" class="container"> + <div class="row"> + <div class="span2"> + <h1 id="logo"><a href="/" title="99s">99s</a></h1> + </div> + <div class="span10"> + + <div id="side-header"> + <nav> + <ul> + <li><a title="Hear my thoughts" href="/articles">Articles</a></li> + <li><a title="Watch my talks" href="/talks">Talks</a></li> + <li class="active"><a title="Read the docs" href="/docs">Documentation</a></li> + <li><a title="Request my services" href="/services">Consulting & Training</a></li> + </ul> + </nav> + <ul id="social"> + <li> + <a href="https://github.com/ninenines" title="Check my Github repositories"><img src="/img/ico_github.png" data-hover="/img/ico_github_alt.png" alt="Github"></a> + </li> + <li> + <a title="Keep in touch!" href="http://twitter.com/lhoguin"><img src="/img/ico_microblog.png" data-hover="/img/ico_microblog_alt.png"></a> + </li> + <li> + <a title="Contact me" href="mailto:[email protected]"><img src="/img/ico_mail.png" data-hover="/img/ico_mail_alt.png"></a> + </li> + </ul> + </div> + </div> + </div> + </div> + + +</header> + +<div id="contents" class="two_col"> +<div class="container"> +<div class="row"> +<div id="docs" class="span9 maincol"> + +<h1 class="lined-header"><span>cowboy_handler(3)</span></h1> + +<div class="sect1">
+<h2 id="_name">Name</h2>
+<div class="sectionbody">
+<div class="paragraph"><p>cowboy_handler - handler middleware and behaviour</p></div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_description">Description</h2>
+<div class="sectionbody">
+<div class="paragraph"><p>The <code>cowboy_handler</code> middleware executes the handler passed
+through the environment values <code>handler</code> and <code>handler_opts</code>,
+and adds the result of this execution to the environment as
+the value <code>result</code>, indicating that the request has been
+handled and received a response.</p></div>
+<div class="paragraph"><p>Environment input:</p></div>
+<div class="dlist"><dl>
+<dt class="hdlist1">
+handler = module()
+</dt>
+<dd>
+<p>
+Handler to be executed.
+</p>
+</dd>
+<dt class="hdlist1">
+handler_opts = any()
+</dt>
+<dd>
+<p>
+Options to be passed to the handler.
+</p>
+</dd>
+</dl></div>
+<div class="paragraph"><p>Environment output:</p></div>
+<div class="dlist"><dl>
+<dt class="hdlist1">
+result = ok
+</dt>
+<dd>
+<p>
+Result of the request.
+</p>
+</dd>
+</dl></div>
+<div class="paragraph"><p>This module also defines the <code>cowboy_handler</code> behaviour that
+defines the basic interface for handlers. All Cowboy handlers
+implement at least the <code>init/2</code> callback, and may implement
+the <code>terminate/3</code> callback optionally.</p></div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_terminate_reasons">Terminate reasons</h2>
+<div class="sectionbody">
+<div class="paragraph"><p>The following values may be received as the terminate reason
+in the optional <code>terminate/3</code> callback. Different handler types
+may define additional terminate reasons.</p></div>
+<div class="dlist"><dl>
+<dt class="hdlist1">
+normal
+</dt>
+<dd>
+<p>
+ The connection was closed normally.
+</p>
+</dd>
+<dt class="hdlist1">
+{crash, Class, Reason}
+</dt>
+<dd>
+<p>
+ A crash occurred in the handler. <code>Class</code> and <code>Reason</code> can be
+ used to obtain more information about the crash. The function
+ <code>erlang:get_stacktrace/0</code> can also be called to obtain the
+ stacktrace of the process when the crash occurred.
+</p>
+</dd>
+</dl></div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_callbacks">Callbacks</h2>
+<div class="sectionbody">
+<div class="sect2">
+<h3 id="_init_req_opts_8594_ok_req_state_module_req_state_module_req_state_hibernate_timeout_module_req_state_timeout_hibernate">init(Req, Opts) → {ok, Req, State} | {Module, Req, State} | {Module, Req, State, hibernate | Timeout} | {Module, Req, State, Timeout, hibernate}</h3>
+<div class="dlist"><dl>
+<dt class="hdlist1">
+Req = cowboy_req:req()
+</dt>
+<dd>
+<p>
+The Req object.
+</p>
+</dd>
+<dt class="hdlist1">
+Opts = any()
+</dt>
+<dd>
+<p>
+Handler options.
+</p>
+</dd>
+<dt class="hdlist1">
+State = any()
+</dt>
+<dd>
+<p>
+Handler state.
+</p>
+</dd>
+<dt class="hdlist1">
+Module = module()
+</dt>
+<dd>
+<p>
+Module of the sub-protocol to use.
+</p>
+</dd>
+<dt class="hdlist1">
+Timeout = timeout()
+</dt>
+<dd>
+<p>
+Timeout passed to the sub-protocol, when applicable.
+</p>
+</dd>
+</dl></div>
+<div class="paragraph"><p>Process the request.</p></div>
+<div class="paragraph"><p>This function can be used to switch to an alternate handler
+type by returning the name of the module to be used, along
+with a few options.</p></div>
+<div class="paragraph"><p>For basic handlers this is the function where the response
+should be sent. If no response is sent, Cowboy will ensure
+that a <code>204 No Content</code> response is sent.</p></div>
+<div class="paragraph"><p>A crash in this callback will result in <code>terminate/3</code> being
+called if it is defined, with the <code>State</code> argument set to
+the value of <code>Opts</code> originally given to the <code>init/2</code> callback.</p></div>
+</div>
+<div class="sect2">
+<h3 id="_terminate_reason_req_state_8594_ok">terminate(Reason, Req, State) → ok</h3>
+<div class="dlist"><dl>
+<dt class="hdlist1">
+Reason = any()
+</dt>
+<dd>
+<p>
+Reason for termination.
+</p>
+</dd>
+<dt class="hdlist1">
+Req = cowboy_req:req()
+</dt>
+<dd>
+<p>
+The Req object.
+</p>
+</dd>
+<dt class="hdlist1">
+State = any()
+</dt>
+<dd>
+<p>
+Handler state.
+</p>
+</dd>
+</dl></div>
+<div class="paragraph"><p>Perform any necessary cleanup of the state.</p></div>
+<div class="paragraph"><p>This callback should release any resource currently in use,
+clear any active timer and reset the process to its original
+state, as it might be reused for future requests sent on the
+same connection. Typical plain HTTP handlers rarely need to
+use it.</p></div>
+<div class="paragraph"><p>A crash in this callback or an invalid return value will
+result in the closing of the connection and the termination
+of the process.</p></div>
+</div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_exports">Exports</h2>
+<div class="sectionbody">
+<div class="sect2">
+<h3 id="_terminate_reason_req_state_handler_8594_ok">terminate(Reason, Req, State, Handler) → ok</h3>
+<div class="dlist"><dl>
+<dt class="hdlist1">
+Reason = any()
+</dt>
+<dd>
+<p>
+Reason for termination.
+</p>
+</dd>
+<dt class="hdlist1">
+Req = cowboy_req:req()
+</dt>
+<dd>
+<p>
+The Req object.
+</p>
+</dd>
+<dt class="hdlist1">
+State = any()
+</dt>
+<dd>
+<p>
+Handler state.
+</p>
+</dd>
+<dt class="hdlist1">
+Handler = module()
+</dt>
+<dd>
+<p>
+Handler module.
+</p>
+</dd>
+</dl></div>
+<div class="paragraph"><p>Call the optional <code>terminate/3</code> callback if it exists.</p></div>
+<div class="paragraph"><p>This function should always be called at the end of the execution
+of a handler, to give it a chance to clean up or perform
+miscellaneous operations.</p></div>
+</div>
+</div>
+</div>
+ + + +</div> + +<div class="span3 sidecol"> + + +<h3> + Cowboy + 2.0 + Function Reference + +</h3> + +<ul> + + <li><a href="/docs/en/cowboy/2.0/guide">User Guide</a></li> + + + <li><a href="/docs/en/cowboy/2.0/manual">Function Reference</a></li> + + +</ul> + +<h4 id="docs-nav">Navigation</h4> + +<h4>Version select</h4> +<ul> + + + + <li><a href="/docs/en/cowboy/1.0/manual">1.0</a></li> + + <li><a href="/docs/en/cowboy/2.0/manual">2.0</a></li> + +</ul> + +</div> +</div> +</div> +</div> + + <footer> + <div class="container"> + <div class="row"> + <div class="span6"> + <p id="scroll-top"><a href="#">↑ Scroll to top</a></p> + <nav> + <ul> + <li><a href="mailto:[email protected]" title="Contact us">Contact us</a></li><li><a href="https://github.com/ninenines/ninenines.github.io" title="Github repository">Contribute to this site</a></li> + </ul> + </nav> + </div> + <div class="span6 credits"> + <p><img src="/img/footer_logo.png"></p> + <p>Copyright © Loïc Hoguin 2012-2016</p> + </div> + </div> + </div> + </footer> + + + <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"></script> + <script src="/js/bootstrap-carousel.js"></script> + <script src="/js/bootstrap-dropdown.js"></script> + <script src="/js/custom.js"></script> + </body> +</html> + + |