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diff --git a/docs/en/cowboy/2.11/manual/cowboy_loop/index.html b/docs/en/cowboy/2.11/manual/cowboy_loop/index.html new file mode 100644 index 00000000..59b141c0 --- /dev/null +++ b/docs/en/cowboy/2.11/manual/cowboy_loop/index.html @@ -0,0 +1,213 @@ +<!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"> + + <title>Nine Nines: cowboy_loop(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=7" 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="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_loop(3)</span></h1> + +<h2 id="_name">Name</h2> +<p>cowboy_loop - Loop handlers</p> +<h2 id="_description">Description</h2> +<p>The module <code>cowboy_loop</code> defines a callback interface for long running HTTP connections.</p> +<p>You should switch to this behavior for long polling, server-sent events and similar long-running requests.</p> +<p>There are generally two usage patterns:</p> +<ul><li>Loop until receiving a specific message, then send a response and stop execution (for example long polling); +</li> +<li>Or initiate a response in <code>init/2</code> and stream the body in <code>info/3</code> as necessary (for example server-sent events). +</li> +</ul> +<h2 id="_callbacks">Callbacks</h2> +<p>Loop handlers implement the following interface:</p> +<div class="listingblock"><div class="content"><!-- Generator: GNU source-highlight 3.1.9 +by Lorenzo Bettini +http://www.lorenzobettini.it +http://www.gnu.org/software/src-highlite --> +<pre><tt><b><font color="#000000">init</font></b>(<font color="#009900">Req</font>, <font color="#009900">State</font>) + <font color="#990000">-></font> {<font color="#FF6600">cowboy_loop</font>, <font color="#009900">Req</font>, <font color="#009900">State</font>} + | {<font color="#FF6600">cowboy_loop</font>, <font color="#009900">Req</font>, <font color="#009900">State</font>, <font color="#FF6600">hibernate</font> | <b><font color="#000000">timeout</font></b>()} + +<b><font color="#000000">info</font></b>(<font color="#009900">Info</font>, <font color="#009900">Req</font>, <font color="#009900">State</font>) + <font color="#990000">-></font> {<font color="#FF6600">ok</font>, <font color="#009900">Req</font>, <font color="#009900">State</font>} + | {<font color="#FF6600">ok</font>, <font color="#009900">Req</font>, <font color="#009900">State</font>, <font color="#FF6600">hibernate</font> | <b><font color="#000000">timeout</font></b>()} + | {<font color="#FF6600">stop</font>, <font color="#009900">Req</font>, <font color="#009900">State</font>} + +<b><font color="#000000">terminate</font></b>(<font color="#009900">Reason</font>, <font color="#009900">Req</font>, <font color="#009900">State</font>) <font color="#990000">-></font> <font color="#FF6600">ok</font> <i><font color="#9A1900">%% optional</font></i> + +<font color="#009900">Req</font> <font color="#990000">::</font> <b><font color="#000000">cowboy_req:req</font></b>() +<font color="#009900">State</font> <font color="#990000">::</font> <b><font color="#000000">any</font></b>() +<font color="#009900">Info</font> <font color="#990000">::</font> <b><font color="#000000">any</font></b>() +<font color="#009900">Reason</font> <font color="#990000">::</font> <font color="#FF6600">stop</font> + | {<font color="#FF6600">crash</font>, <font color="#FF6600">error</font> | <b><font color="#000080">exit</font></b> | <b><font color="#000080">throw</font></b>, <b><font color="#000000">any</font></b>()}</tt></pre> +</div></div> +<p>The <code>init/2</code> callback is common to all handlers. To switch to the loop behavior, it must return <code>cowboy_loop</code> as the first element of the tuple.</p> +<p>The <code>info/3</code> callback will be called for every Erlang message received. It may choose to continue the receive loop or stop it.</p> +<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> +<p>The following terminate reasons are defined for loop handlers:</p> +<dl><dt>stop</dt> +<dd><p>The handler requested to close the connection by returning a <code>stop</code> tuple.</p> +</dd> +<dt>{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.</p> +</dd> +</dl> +<h2 id="_changelog">Changelog</h2> +<ul><li><strong>2.11</strong>: A timeout may be returned instead of <code>hibernate</code>. It functions the same way as the <code>gen_server</code> timeout. +</li> +<li><strong>2.0</strong>: Loop handlers no longer need to handle socket events. +</li> +<li><strong>1.0</strong>: Behavior introduced. +</li> +</ul> +<h2 id="_see_also">See also</h2> +<p><a href="..">cowboy(7)</a>, <a href="../cowboy_handler">cowboy_handler(3)</a></p> + + + + + + +</div> + +<div class="span3 sidecol"> + + +<h3> + Cowboy + 2.11 + Function Reference + +</h3> + +<ul> + + <li><a href="/docs/en/cowboy/2.11/guide">User Guide</a></li> + + + <li><a href="/docs/en/cowboy/2.11/manual">Function Reference</a></li> + + +</ul> + +<h4 id="docs-nav">Navigation</h4> + +<h4>Version select</h4> +<ul> + + + + <li><a href="/docs/en/cowboy/2.11/manual">2.11</a></li> + + <li><a href="/docs/en/cowboy/2.10/manual">2.10</a></li> + + <li><a href="/docs/en/cowboy/2.9/manual">2.9</a></li> + + <li><a href="/docs/en/cowboy/2.8/manual">2.8</a></li> + + <li><a href="/docs/en/cowboy/2.7/manual">2.7</a></li> + + <li><a href="/docs/en/cowboy/2.6/manual">2.6</a></li> + +</ul> + +<h3 id="_like_my_work__donate">Like my work? 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