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diff --git a/docs/en/cowboy/2.3/guide/ws_protocol/index.html b/docs/en/cowboy/2.3/guide/ws_protocol/index.html new file mode 100644 index 00000000..7ebb086c --- /dev/null +++ b/docs/en/cowboy/2.3/guide/ws_protocol/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 0.37.1" /> + + <title>Nine Nines: The Websocket protocol</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>The Websocket protocol</span></h1> + +<div class="paragraph"><p>This chapter explains what Websocket is and why it is +a vital component of soft realtime Web applications.</p></div> +<div class="sect1"> +<h2 id="_description">Description</h2> +<div class="sectionbody"> +<div class="paragraph"><p>Websocket is an extension to HTTP that emulates plain TCP +connections between the client, typically a Web browser, +and the server. It uses the HTTP Upgrade mechanism to +establish the connection.</p></div> +<div class="paragraph"><p>Websocket connections are fully asynchronous, unlike +HTTP/1.1 (synchronous) and HTTP/2 (asynchronous, but the +server can only initiate streams in response to requests). +With Websocket, the client and the server can both send +frames at any time without any restriction. It is closer +to TCP than any of the HTTP protocols.</p></div> +<div class="paragraph"><p>Websocket is an IETF standard. Cowboy supports the standard +and all drafts that were previously implemented by browsers, +excluding the initial flawed draft sometimes known as +"version 0".</p></div> +</div> +</div> +<div class="sect1"> +<h2 id="_websocket_vs_http_2">Websocket vs HTTP/2</h2> +<div class="sectionbody"> +<div class="paragraph"><p>For a few years Websocket was the only way to have a +bidirectional asynchronous connection with the server. +This changed when HTTP/2 was introduced. While HTTP/2 +requires the client to first perform a request before +the server can push data, this is only a minor restriction +as the client can do so just as it connects.</p></div> +<div class="paragraph"><p>Websocket was designed as a kind-of-TCP channel to a +server. It only defines the framing and connection +management and lets the developer implement a protocol +on top of it. For example you could implement IRC over +Websocket and use a Javascript IRC client to speak to +the server.</p></div> +<div class="paragraph"><p>HTTP/2 on the other hand is just an improvement over +the HTTP/1.1 connection and request/response mechanism. +It has the same semantics as HTTP/1.1.</p></div> +<div class="paragraph"><p>If all you need is to access an HTTP API, then HTTP/2 +should be your first choice. On the other hand, if what +you need is a different protocol, then you can use +Websocket to implement it.</p></div> +</div> +</div> +<div class="sect1"> +<h2 id="_implementation">Implementation</h2> +<div class="sectionbody"> +<div class="paragraph"><p>Cowboy implements Websocket as a protocol upgrade. Once the +upgrade is performed from the <code>init/2</code> callback, Cowboy +switches to Websocket. Please consult the next chapter for +more information on initiating and handling Websocket +connections.</p></div> +<div class="paragraph"><p>The implementation of Websocket in Cowboy is validated using +the Autobahn test suite, which is an extensive suite of tests +covering all aspects of the protocol. Cowboy passes the +suite with 100% success, including all optional tests.</p></div> +<div class="paragraph"><p>Cowboy’s Websocket implementation also includes the +permessage-deflate and x-webkit-deflate-frame compression +extensions.</p></div> +<div class="paragraph"><p>Cowboy will automatically use compression when the +<code>compress</code> option is returned from the <code>init/2</code> function.</p></div> +</div> +</div> + + + + + + + + + + + <nav style="margin:1em 0"> + + <a style="float:left" href="https://ninenines.eu/docs/en/cowboy/2.3/guide/resource_design/"> + Designing a resource handler + </a> + + + + <a style="float:right" href="https://ninenines.eu/docs/en/cowboy/2.3/guide/ws_handlers/"> + Websocket handlers + </a> + + </nav> + + + + +</div> + +<div class="span3 sidecol"> + + +<h3> + Cowboy + 2.3 + + User Guide +</h3> + +<ul> + + <li><a href="/docs/en/cowboy/2.3/guide">User Guide</a></li> + + + <li><a href="/docs/en/cowboy/2.3/manual">Function Reference</a></li> + + +</ul> + +<h4 id="docs-nav">Navigation</h4> + +<h4>Version select</h4> +<ul> + + + + <li><a href="/docs/en/cowboy/2.3/guide">2.3</a></li> + + <li><a href="/docs/en/cowboy/2.2/guide">2.2</a></li> + + <li><a href="/docs/en/cowboy/2.1/guide">2.1</a></li> + + <li><a href="/docs/en/cowboy/2.0/guide">2.0</a></li> + + <li><a href="/docs/en/cowboy/1.0/guide">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> + + |