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diff --git a/docs/en/cowboy/2.1/manual/cowboy_handler/index.html b/docs/en/cowboy/2.1/manual/cowboy_handler/index.html new file mode 100644 index 00000000..e83b6fab --- /dev/null +++ b/docs/en/cowboy/2.1/manual/cowboy_handler/index.html @@ -0,0 +1,231 @@ +<!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 0.30.2" /> + + <title>Nine Nines: cowboy_handler(3)</title> + + <link href='https://fonts.googleapis.com/css?family=Open+Sans:400,700,400italic' rel='stylesheet' type='text/css'> + <link href="/css/99s.css?r=1" 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 - Plain HTTP handlers</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 selected +by the router or any other preceding middleware.</p></div> +<div class="paragraph"><p>This middleware takes the handler module and initial state +from the <code>handler</code> and <code>handler_opts</code> environment values, +respectively. On completion, it adds a <code>result</code> value to +the middleware environment, containing the return value +of the <code>terminate/3</code> callback (if defined) and <code>ok</code> otherwise.</p></div> +<div class="paragraph"><p>This module also defines a callback interface for handling +HTTP requests.</p></div> +</div> +</div> +<div class="sect1"> +<h2 id="_callbacks">Callbacks</h2> +<div class="sectionbody"> +<div class="paragraph"><p>Plain HTTP handlers implement the following interface:</p></div> +<div class="listingblock"> +<div class="content"><!-- Generator: GNU source-highlight 3.1.8 +by Lorenzo Bettini +http://www.lorenzobettini.it +http://www.gnu.org/software/src-highlite --> +<pre><tt><span style="font-weight: bold"><span style="color: #000000">init</span></span>(<span style="color: #009900">Req</span>, <span style="color: #009900">State</span>) <span style="color: #990000">-></span> {<span style="color: #FF6600">ok</span>, <span style="color: #009900">Req</span>, <span style="color: #009900">State</span>} + +<span style="font-weight: bold"><span style="color: #000000">terminate</span></span>(<span style="color: #009900">Reason</span>, <span style="color: #009900">Req</span>, <span style="color: #009900">State</span>) <span style="color: #990000">-></span> <span style="color: #FF6600">ok</span> <span style="font-style: italic"><span style="color: #9A1900">%% optional</span></span> + +<span style="color: #009900">Req</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000000">cowboy_req:req</span></span>() +<span style="color: #009900">State</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000000">any</span></span>() +<span style="color: #009900">Reason</span> <span style="color: #990000">::</span> <span style="font-weight: bold"><span style="color: #000080">normal</span></span> + | {<span style="color: #FF6600">crash</span>, <span style="color: #FF6600">error</span> | <span style="font-weight: bold"><span style="color: #000080">exit</span></span> | <span style="font-weight: bold"><span style="color: #000080">throw</span></span>, <span style="font-weight: bold"><span style="color: #000000">any</span></span>()}</tt></pre></div></div> +<div class="paragraph"><p>These two callbacks are common to all handlers.</p></div> +<div class="paragraph"><p>Plain HTTP handlers do all their work in the <code>init/2</code> +callback. Returning <code>ok</code> terminates the handler. If no +response is sent, Cowboy will send a <code>204 No Content</code>.</p></div> +<div class="paragraph"><p>The optional <code>terminate/3</code> 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.</p></div> +<div class="paragraph"><p>The following terminate reasons are defined for plain HTTP +handlers:</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="_exports">Exports</h2> +<div class="sectionbody"> +<div class="paragraph"><p>The following function should be called by modules implementing +custom handlers to execute the optional terminate callback:</p></div> +<div class="ulist"><ul> +<li> +<p> +<a href="../cowboy_handler.terminate">cowboy_handler:terminate(3)</a> - Terminate the handler +</p> +</li> +</ul></div> +</div> +</div> +<div class="sect1"> +<h2 id="_see_also">See also</h2> +<div class="sectionbody"> +<div class="paragraph"><p><a href="..">cowboy(7)</a></p></div> +</div> +</div> + + + + + +</div> + +<div class="span3 sidecol"> + + +<h3> + Cowboy + 2.1 + Function Reference + +</h3> + +<ul> + + <li><a href="/docs/en/cowboy/2.1/guide">User Guide</a></li> + + + <li><a href="/docs/en/cowboy/2.1/manual">Function Reference</a></li> + + +</ul> + +<h4 id="docs-nav">Navigation</h4> + +<h4>Version select</h4> +<ul> + + + + <li><a href="/docs/en/cowboy/2.1/manual">2.1</a></li> + + <li><a href="/docs/en/cowboy/2.0/manual">2.0</a></li> + + <li><a href="/docs/en/cowboy/1.0/manual">1.0</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="/js/custom.js"></script> + </body> +</html> + + |