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diff --git a/docs/en/ranch/1.4/guide/protocols/index.html b/docs/en/ranch/1.4/guide/protocols/index.html new file mode 100644 index 00000000..eef4ca91 --- /dev/null +++ b/docs/en/ranch/1.4/guide/protocols/index.html @@ -0,0 +1,261 @@ +<!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 0.26" /> + + <title>Nine Nines: Protocols</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>Protocols</span></h1> + +<div class="paragraph"><p>A protocol handler starts a connection process and defines the +protocol logic executed in this process.</p></div> +<div class="sect1"> +<h2 id="_writing_a_protocol_handler">Writing a protocol handler</h2> +<div class="sectionbody"> +<div class="paragraph"><p>All protocol handlers must implement the <code>ranch_protocol</code> behavior +which defines a single callback, <code>start_link/4</code>. This callback is +responsible for spawning a new process for handling the connection. +It receives four arguments: the name of the listener, the socket, the +transport handler being used and the protocol options defined in +the call to <code>ranch:start_listener/5</code>. This callback must +return <code>{ok, Pid}</code>, with <code>Pid</code> the pid of the new process.</p></div> +<div class="paragraph"><p>The newly started process can then freely initialize itself. However, +it must call <code>ranch:accept_ack/1</code> before doing any socket operation. +This will ensure the connection process is the owner of the socket. +It expects the listener’s name as argument.</p></div> +<div class="listingblock"> +<div class="title">Acknowledge accepting the socket</div> +<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="color: #0000FF">ok</span> <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">ranch:accept_ack</span></span>(<span style="color: #009900">Ref</span>)<span style="color: #990000">.</span></tt></pre></div></div> +<div class="paragraph"><p>If your protocol code requires specific socket options, you should +set them while initializing your connection process, after +calling <code>ranch:accept_ack/1</code>. You can use <code>Transport:setopts/2</code> +for that purpose.</p></div> +<div class="paragraph"><p>Following is the complete protocol code for the example found +in <code>examples/tcp_echo/</code>.</p></div> +<div class="listingblock"> +<div class="title">Protocol module that echoes everything it receives</div> +<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: #000080">-module</span></span>(<span style="color: #FF6600">echo_protocol</span>)<span style="color: #990000">.</span> +<span style="font-weight: bold"><span style="color: #000080">-behaviour</span></span>(<span style="color: #FF6600">ranch_protocol</span>)<span style="color: #990000">.</span> + +<span style="font-weight: bold"><span style="color: #000080">-export</span></span>([<span style="font-weight: bold"><span style="color: #000000">start_link</span></span><span style="color: #990000">/</span><span style="color: #993399">4</span>])<span style="color: #990000">.</span> +<span style="font-weight: bold"><span style="color: #000080">-export</span></span>([<span style="font-weight: bold"><span style="color: #000000">init</span></span><span style="color: #990000">/</span><span style="color: #993399">4</span>])<span style="color: #990000">.</span> + +<span style="font-weight: bold"><span style="color: #000000">start_link</span></span>(<span style="color: #009900">Ref</span>, <span style="color: #009900">Socket</span>, <span style="color: #009900">Transport</span>, <span style="color: #009900">Opts</span>) <span style="color: #990000">-></span> + <span style="color: #009900">Pid</span> <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000080">spawn_link</span></span>(<span style="font-weight: bold"><span style="color: #000080">?MODULE</span></span>, <span style="color: #FF6600">init</span>, [<span style="color: #009900">Ref</span>, <span style="color: #009900">Socket</span>, <span style="color: #009900">Transport</span>, <span style="color: #009900">Opts</span>]), + {<span style="color: #FF6600">ok</span>, <span style="color: #009900">Pid</span>}<span style="color: #990000">.</span> + +<span style="font-weight: bold"><span style="color: #000000">init</span></span>(<span style="color: #009900">Ref</span>, <span style="color: #009900">Socket</span>, <span style="color: #009900">Transport</span>, <span style="color: #009900">_Opts</span> <span style="color: #990000">=</span> []) <span style="color: #990000">-></span> + <span style="color: #0000FF">ok</span> <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">ranch:accept_ack</span></span>(<span style="color: #009900">Ref</span>), + <span style="font-weight: bold"><span style="color: #000000">loop</span></span>(<span style="color: #009900">Socket</span>, <span style="color: #009900">Transport</span>)<span style="color: #990000">.</span> + +<span style="font-weight: bold"><span style="color: #000000">loop</span></span>(<span style="color: #009900">Socket</span>, <span style="color: #009900">Transport</span>) <span style="color: #990000">-></span> + <span style="font-weight: bold"><span style="color: #0000FF">case</span></span> <span style="color: #009900">Transport</span><span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #000000">recv</span></span>(<span style="color: #009900">Socket</span>, <span style="color: #993399">0</span>, <span style="color: #993399">5000</span>) <span style="font-weight: bold"><span style="color: #0000FF">of</span></span> + {<span style="color: #FF6600">ok</span>, <span style="color: #009900">Data</span>} <span style="color: #990000">-></span> + <span style="color: #009900">Transport</span><span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #000000">send</span></span>(<span style="color: #009900">Socket</span>, <span style="color: #009900">Data</span>), + <span style="font-weight: bold"><span style="color: #000000">loop</span></span>(<span style="color: #009900">Socket</span>, <span style="color: #009900">Transport</span>); + <span style="color: #990000">_</span> <span style="color: #990000">-></span> + <span style="color: #0000FF">ok</span> <span style="color: #990000">=</span> <span style="color: #009900">Transport</span><span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #000000">close</span></span>(<span style="color: #009900">Socket</span>) + <span style="font-weight: bold"><span style="color: #0000FF">end</span></span><span style="color: #990000">.</span></tt></pre></div></div> +</div> +</div> +<div class="sect1"> +<h2 id="_using_gen_server">Using gen_server</h2> +<div class="sectionbody"> +<div class="paragraph"><p>Special processes like the ones that use the <code>gen_server</code> or <code>gen_fsm</code> +behaviours have the particularity of having their <code>start_link</code> call not +return until the <code>init</code> function returns. This is problematic, because +you won’t be able to call <code>ranch:accept_ack/1</code> from the <code>init</code> callback +as this would cause a deadlock to happen.</p></div> +<div class="paragraph"><p>Use the <code>gen_server:enter_loop/3</code> function. It allows you to start your process +normally (although it must be started with <code>proc_lib</code> like all special +processes), then perform any needed operations before falling back into +the normal <code>gen_server</code> execution loop.</p></div> +<div class="listingblock"> +<div class="title">Use a gen_server for protocol handling</div> +<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: #000080">-module</span></span>(<span style="color: #FF6600">my_protocol</span>)<span style="color: #990000">.</span> +<span style="font-weight: bold"><span style="color: #000080">-behaviour</span></span>(<span style="color: #FF6600">gen_server</span>)<span style="color: #990000">.</span> +<span style="font-weight: bold"><span style="color: #000080">-behaviour</span></span>(<span style="color: #FF6600">ranch_protocol</span>)<span style="color: #990000">.</span> + +<span style="font-weight: bold"><span style="color: #000080">-export</span></span>([<span style="font-weight: bold"><span style="color: #000000">start_link</span></span><span style="color: #990000">/</span><span style="color: #993399">4</span>])<span style="color: #990000">.</span> +<span style="font-weight: bold"><span style="color: #000080">-export</span></span>([<span style="font-weight: bold"><span style="color: #000000">init</span></span><span style="color: #990000">/</span><span style="color: #993399">1</span>])<span style="color: #990000">.</span> +<span style="font-style: italic"><span style="color: #9A1900">%% Exports of other gen_server callbacks here.</span></span> + +<span style="font-weight: bold"><span style="color: #000000">start_link</span></span>(<span style="color: #009900">Ref</span>, <span style="color: #009900">Socket</span>, <span style="color: #009900">Transport</span>, <span style="color: #009900">Opts</span>) <span style="color: #990000">-></span> + {<span style="color: #FF6600">ok</span>, <span style="font-weight: bold"><span style="color: #000000">proc_lib:spawn_link</span></span>(<span style="font-weight: bold"><span style="color: #000080">?MODULE</span></span>, <span style="color: #FF6600">init</span>, [{<span style="color: #009900">Ref</span>, <span style="color: #009900">Socket</span>, <span style="color: #009900">Transport</span>, <span style="color: #009900">Opts</span>}])}<span style="color: #990000">.</span> + +<span style="font-weight: bold"><span style="color: #000000">init</span></span>({<span style="color: #009900">Ref</span>, <span style="color: #009900">Socket</span>, <span style="color: #009900">Transport</span>, <span style="color: #009900">_Opts</span> <span style="color: #990000">=</span> []}) <span style="color: #990000">-></span> + <span style="font-style: italic"><span style="color: #9A1900">%% Perform any required state initialization here.</span></span> + <span style="color: #0000FF">ok</span> <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">ranch:accept_ack</span></span>(<span style="color: #009900">Ref</span>), + <span style="color: #0000FF">ok</span> <span style="color: #990000">=</span> <span style="color: #009900">Transport</span><span style="color: #990000">:</span><span style="font-weight: bold"><span style="color: #000000">setopts</span></span>(<span style="color: #009900">Socket</span>, [{<span style="color: #FF6600">active</span>, <span style="color: #FF6600">once</span>}]), + <span style="font-weight: bold"><span style="color: #000000">gen_server:enter_loop</span></span>(<span style="font-weight: bold"><span style="color: #000080">?MODULE</span></span>, [], {<span style="color: #FF6600">state</span>, <span style="color: #009900">Socket</span>, <span style="color: #009900">Transport</span>})<span style="color: #990000">.</span> + +<span style="font-style: italic"><span style="color: #9A1900">%% Other gen_server callbacks here.</span></span></tt></pre></div></div> +<div class="paragraph"><p>Check the <code>tcp_reverse</code> example for a complete example.</p></div> +</div> +</div> + + + + + + + + + + + <nav style="margin:1em 0"> + + <a style="float:left" href="https://ninenines.eu/docs/en/ranch/1.4/guide/transports/"> + Transports + </a> + + + + <a style="float:right" href="https://ninenines.eu/docs/en/ranch/1.4/guide/embedded/"> + Embedded mode + </a> + + </nav> + + + + +</div> + +<div class="span3 sidecol"> + + +<h3> + Ranch + 1.4 + + User Guide +</h3> + +<ul> + + <li><a href="/docs/en/ranch/1.4/guide">User Guide</a></li> + + + <li><a href="/docs/en/ranch/1.4/manual">Function Reference</a></li> + + +</ul> + +<h4 id="docs-nav">Navigation</h4> + +<h4>Version select</h4> +<ul> + + + + <li><a href="/docs/en/ranch/1.4/guide">1.4</a></li> + + <li><a href="/docs/en/ranch/1.3/guide">1.3</a></li> + + <li><a 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