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diff --git a/docs/en/cowboy/2.0/guide/sub_protocols/index.html b/docs/en/cowboy/2.0/guide/sub_protocols/index.html new file mode 100644 index 00000000..c75da6a4 --- /dev/null +++ b/docs/en/cowboy/2.0/guide/sub_protocols/index.html @@ -0,0 +1,206 @@ +<!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: Sub protocols</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>Sub protocols</span></h1> + +<div class="paragraph"><p>Sub protocols are used for creating new types of handlers that
+provide extra functionality in a reusable way. Cowboy uses this
+mechanism to provide its loop, REST and Websocket handlers.</p></div>
+<div class="paragraph"><p>This chapter will explain how to create your own sub protocols
+and handler types.</p></div>
+<div class="sect1">
+<h2 id="_usage">Usage</h2>
+<div class="sectionbody">
+<div class="paragraph"><p>To switch to a sub protocol, the <code>init/2</code> callback must return
+the name of the sub protocol module. Everything past this point
+is handled by the sub protocol.</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">_Opts</span>) <span style="color: #990000">-></span>
+ {<span style="color: #FF6600">cowboy_websocket</span>, <span style="color: #009900">Req</span>, <span style="color: #008080">#state</span>{}}<span style="color: #990000">.</span></tt></pre></div></div>
+<div class="paragraph"><p>The return value may also have a <code>Timeout</code> value and/or the
+atom <code>hibernate</code>. These options are useful for long living
+connections. When they are not provided, the timeout value
+defaults to <code>infinity</code> and the hibernate value to <code>run</code>.</p></div>
+<div class="paragraph"><p>The following snippet switches to the <code>my_protocol</code> sub
+protocol, sets the timeout value to 5 seconds and enables
+hibernation:</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">_Opts</span>) <span style="color: #990000">-></span>
+ {<span style="color: #FF6600">my_protocol</span>, <span style="color: #009900">Req</span>, <span style="color: #008080">#state</span>{}, <span style="color: #993399">5000</span>, <span style="color: #FF6600">hibernate</span>}<span style="color: #990000">.</span></tt></pre></div></div>
+<div class="paragraph"><p>If a sub protocol does not make use of these options, it should
+crash if it receives anything other than the default values.</p></div>
+</div>
+</div>
+<div class="sect1">
+<h2 id="_upgrade">Upgrade</h2>
+<div class="sectionbody">
+<div class="paragraph"><p>After the <code>init/2</code> function returns, Cowboy will then call the
+<code>upgrade/6</code> function. This is the only callback defined by the
+<code>cowboy_sub_protocol</code> behavior.</p></div>
+<div class="paragraph"><p>The function is named <code>upgrade</code> because it mimics the mechanism
+of HTTP protocol upgrades. For some sub protocols, like Websocket,
+an actual upgrade is performed. For others, like REST, this is
+only an upgrade at Cowboy’s level and the client has nothing to
+do about it.</p></div>
+<div class="paragraph"><p>The upgrade callback receives the Req object, the middleware
+environment, the handler and its options, and the aforementioned
+timeout and hibernate values.</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">upgrade</span></span>(<span style="color: #009900">Req</span>, <span style="color: #009900">Env</span>, <span style="color: #009900">Handler</span>, <span style="color: #009900">HandlerOpts</span>, <span style="color: #009900">Timeout</span>, <span style="color: #009900">Hibernate</span>) <span style="color: #990000">-></span>
+ <span style="font-style: italic"><span style="color: #9A1900">%% Sub protocol code here.</span></span></tt></pre></div></div>
+<div class="paragraph"><p>This callback is expected to behave like a middleware and to
+return an updated environment and Req object.</p></div>
+<div class="paragraph"><p>Sub protocols are expected to call the <code>cowboy_handler:terminate/4</code>
+function when they terminate. This function will make sure that
+the optional <code>terminate/3</code> callback is called, if present.</p></div>
+</div>
+</div>
+ + + +</div> + +<div class="span3 sidecol"> + + +<h3> + Cowboy + 2.0 + + User Guide +</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/guide">1.0</a></li> + + <li><a href="/docs/en/cowboy/2.0/guide">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> + + |