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diff --git a/_build/static/docs/en/cowboy/1.0/guide/middlewares/index.html b/_build/static/docs/en/cowboy/1.0/guide/middlewares/index.html new file mode 100644 index 00000000..42410512 --- /dev/null +++ b/_build/static/docs/en/cowboy/1.0/guide/middlewares/index.html @@ -0,0 +1,226 @@ +<!DOCTYPE html> +<html lang="en"> + <head> + <meta charset="utf-8"> + <title>Nine Nines Support: Cowboy User Guide</title> + <meta name="viewport" content="width=device-width, initial-scale=1.0"> + <!-- Change them or set them up as you like --> + <meta name="description" content=""> + <meta name="author" content="(Soft10) Pol Cámara"> + + <!-- Stylesheets --> + <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 href="js/google-code-prettify/prettify.css" rel="stylesheet"> --> + <link href="/css/sh99s.css" rel="stylesheet"/> + + <!-- Enables html5 support on older browsers, other js is placed at the end of the page to speed up loading --> + <!--[if lt IE 9]> + <script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script> + <![endif]--> + + <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"> + <link rel="alternate" href="/feeds/atom.xml" type="application/atom+xml" title="Nine Nines Atom Feed"> + </head> + + <body class="big_text docs"> + <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"> + <!-- Top navigation and social icons--> + <div id="side-header"> + <nav> + <ul> + <li><a title="Erlang training" href="/training">Training</a></li> + <li><a title="Technical publications" href="/articles">Articles</a></li> + <li><a title="Our talks" href="/talks">Talks</a></li> + <li class="active"><a title="Our services" href="/support">Pricing & Sponsoring</a></li> + <li><a title="Community support" href="http://lists.ninenines.eu">Mailing Lists</a></li> + <li><a title="Contact us" href="mailto:[email protected]">Contact</a></li> + </ul> + </nav> + <ul id="social"> + <li> + <a href="https://github.com/ninenines" title="Check our Github repositories"><img src="/img/ico_github.png" data-hover="/img/ico_github_alt.png" alt="Github"></a> + </li> + <li class="dropdown" id="twitter-links"> + <a href="#twitter-links" class="dropdown-toggle" data-toggle="dropdown" title="Follow us on Twitter"> + <img src="/img/ico_twitter.png" data-hover="/img/ico_twitter_alt.png" alt="Twitter"> + </a> + <ul class="dropdown-menu"> + <li><a title="Visit Loïc Hoguin's Twitter Account" href="http://twitter.com/lhoguin">@lhoguin</a></li> + <!-- <li class="divider"></li> + <li><a title="Visit our official Twitter account" href="#">@99s</a></li> --> + </ul> + </li> + <!-- <li> + <a href="/css/" title="Add us on Linkedin"><img src="/img/ico_linkedin.png" data-hover="img/ico_linkedin_alt.png" alt="Linkedin"></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>Middlewares</span></h1> + +<p>Cowboy delegates the request processing to middleware components. By default, two middlewares are defined, for the routing and handling of the request, as is detailed in most of this guide.</p> + +<p>Middlewares give you complete control over how requests are to be processed. You can add your own middlewares to the mix or completely change the chain of middlewares as needed.</p> + +<p>Cowboy will execute all middlewares in the given order, unless one of them decides to stop processing.</p> + +<h2 id="usage">Usage</h2> + +<p>Middlewares only need to implement a single callback: <code>execute/2</code>. It is defined in the <code>cowboy_middleware</code> behavior.</p> + +<p>This callback has two arguments. The first is the <code>Req</code> object. The second is the environment.</p> + +<p>Middlewares can return one of four different values:</p> + +<ul> +<li><code>{ok, Req, Env}</code> to continue the request processing</li> +<li><code>{suspend, Module, Function, Args}</code> to hibernate</li> +<li><code>{halt, Req}</code> to stop processing and move on to the next request</li> +<li><code>{error, StatusCode, Req}</code> to reply an error and close the socket</li> +</ul> + +<p>Of note is that when hibernating, processing will resume on the given MFA, discarding all previous stacktrace. Make sure you keep the <code>Req</code> and <code>Env</code> in the arguments of this MFA for later use.</p> + +<p>If an error happens during middleware processing, Cowboy will not try to send an error back to the socket, the process will just crash. It is up to the middleware to make sure that a reply is sent if something goes wrong.</p> + +<h2 id="configuration">Configuration</h2> + +<p>The middleware environment is defined as the <code>env</code> protocol option. In the previous chapters we saw it briefly when we needed to pass the routing information. It is a list of tuples with the first element being an atom and the second any Erlang term.</p> + +<p>Two values in the environment are reserved:</p> + +<ul> +<li><code>listener</code> contains the name of the listener</li> +<li><code>result</code> contains the result of the processing</li> +</ul> + +<p>The <code>listener</code> value is always defined. The <code>result</code> value can be set by any middleware. If set to anything other than <code>ok</code>, Cowboy will not process any subsequent requests on this connection.</p> + +<p>The middlewares that come with Cowboy may define or require other environment values to perform.</p> + +<p>You can update the environment by calling the <code>cowboy:set_env/3</code> convenience function, adding or replacing a value in the environment.</p> + +<h2 id="routing_middleware">Routing middleware</h2> + +<p>The routing middleware requires the <code>dispatch</code> value. If routing succeeds, it will put the handler name and options in the <code>handler</code> and <code>handler_opts</code> values of the environment, respectively.</p> + +<h2 id="handler_middleware">Handler middleware</h2> + +<p>The handler middleware requires the <code>handler</code> and <code>handler_opts</code> values. It puts the result of the request handling into <code>result</code>.</p> + + +<!-- a.code --> +</div> + +<div class="span3 sidecol"> +<div class="input-append"> +<form id="form-search" class="form-search" action="#"> + <input id="input-search" type="text" placeholder="Function search" autocomplete="off" autofocus class="input-medium search-query span2"> + <button type="submit" class="btn btn-success">Go</button> +</form> +</div> + +<h3 id="docs-nav">Navigation</h3> + +<h3>See also</h3><ul><li><a href="/docs/en/cowboy/1.0/manual/">Function Reference</a></li><li><a href="/docs/en/cowboy/1.0/index.html">README</a></li></ul> + +<h3>Version select</h3> +<ul> + + <li><a href="/docs/en/cowboy/1.0/guide/"><strong>1.0</strong></a></li> + + <li><a href="/docs/en/cowboy/HEAD/guide/"><strong>HEAD</strong></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 © Nine Nines 2012-2014</p> + </div> + </div> + </div> + </footer> + + <!-- Javascript --> + <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> + + +<script type="text/javascript" src="/js/shCore.js"></script> +<script type="text/javascript" src="/js/shlang/shBrushBash.js"></script> +<script type="text/javascript" src="/js/shlang/shBrushErlang.js"></script> +<script type="text/javascript" src="/js/shlang/shBrushJScript.js"></script> +<script type="text/javascript" src="/js/shlang/shBrushPlain.js"></script> +<script type="text/javascript">SyntaxHighlighter.all();</script> + +<script type="text/javascript" src="/js/fuse.min.js"></script> +<script type="text/javascript"> +$(document).ready(function(){ + var f; + + $.getJSON("/docs/db.json", function(data){ + f = new Fuse(data, {keys: ["n"], threshold: 0.3}); + $("<ul id=\"search-results\">").insertAfter("#form-search"); + }); + + $("#input-search").keyup(function(e){if(f){if (e.which != 13 ){ + var results = f.search($(this).val()); + if (results.length == 0){ + $("#form-search").attr("action", "#"); + }else{ + $("#form-search").attr("action", results[0].l); + } + + $("#search-results").empty(); + for (var i = 0; i < 10 && i < results.length; i++){ + $("<li><a href=\"" + results[i].l + "\">" + results[i].n + "</a></li>") + .appendTo("#search-results"); + } + }}}); +}); +</script> + + </body> +</html> |