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diff --git a/docs/en/ranch/1.8/guide/protocols/index.html b/docs/en/ranch/1.8/guide/protocols/index.html new file mode 100644 index 00000000..427423c2 --- /dev/null +++ b/docs/en/ranch/1.8/guide/protocols/index.html @@ -0,0 +1,248 @@ +<!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: 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=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>Protocols</span></h1> + +<p>A protocol handler starts a connection process and defines the protocol logic executed in this process.</p> +<h2 id="_writing_a_protocol_handler">Writing a protocol handler</h2> +<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> +<p>The newly started process can then freely initialize itself. However, it must call <code>ranch:handshake/1,2</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 class="listingblock"><div class="title">Perform the socket handshake</div> +<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>{<font color="#FF6600">ok</font>, <font color="#009900">Socket</font>} <font color="#990000">=</font> <b><font color="#000000">ranch:handshake</font></b>(<font color="#009900">Ref</font>)<font color="#990000">.</font></tt></pre> +</div></div> +<p>If your protocol code requires specific socket options, you should set them while initializing your connection process, after calling <code>ranch:handshake/1,2</code>. You can use <code>Transport:setopts/2</code> for that purpose.</p> +<p>Following is the complete protocol code for the example found in <code>examples/tcp_echo/</code>.</p> +<div class="listingblock"><div class="title">Protocol module that echoes everything it receives</div> +<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="#000080">-module</font></b>(<font color="#FF6600">echo_protocol</font>)<font color="#990000">.</font> +<b><font color="#000080">-behaviour</font></b>(<font color="#FF6600">ranch_protocol</font>)<font color="#990000">.</font> + +<b><font color="#000080">-export</font></b>([<b><font color="#000000">start_link</font></b><font color="#990000">/</font><font color="#993399">4</font>])<font color="#990000">.</font> +<b><font color="#000080">-export</font></b>([<b><font color="#000000">init</font></b><font color="#990000">/</font><font color="#993399">3</font>])<font color="#990000">.</font> + +<b><font color="#000000">start_link</font></b>(<font color="#009900">Ref</font>, <font color="#009900">_Socket</font>, <font color="#009900">Transport</font>, <font color="#009900">Opts</font>) <font color="#990000">-></font> + <font color="#009900">Pid</font> <font color="#990000">=</font> <b><font color="#000080">spawn_link</font></b>(<b><font color="#000080">?MODULE</font></b>, <font color="#FF6600">init</font>, [<font color="#009900">Ref</font>, <font color="#009900">Transport</font>, <font color="#009900">Opts</font>]), + {<font color="#FF6600">ok</font>, <font color="#009900">Pid</font>}<font color="#990000">.</font> + +<b><font color="#000000">init</font></b>(<font color="#009900">Ref</font>, <font color="#009900">Transport</font>, <font color="#009900">_Opts</font> <font color="#990000">=</font> []) <font color="#990000">-></font> + {<font color="#FF6600">ok</font>, <font color="#009900">Socket</font>} <font color="#990000">=</font> <b><font color="#000000">ranch:handshake</font></b>(<font color="#009900">Ref</font>), + <b><font color="#000000">loop</font></b>(<font color="#009900">Socket</font>, <font color="#009900">Transport</font>)<font color="#990000">.</font> + +<b><font color="#000000">loop</font></b>(<font color="#009900">Socket</font>, <font color="#009900">Transport</font>) <font color="#990000">-></font> + <b><font color="#0000FF">case</font></b> <font color="#009900">Transport</font><font color="#990000">:</font><b><font color="#000000">recv</font></b>(<font color="#009900">Socket</font>, <font color="#993399">0</font>, <font color="#993399">5000</font>) <b><font color="#0000FF">of</font></b> + {<font color="#FF6600">ok</font>, <font color="#009900">Data</font>} <font color="#990000">-></font> + <font color="#009900">Transport</font><font color="#990000">:</font><b><font color="#000000">send</font></b>(<font color="#009900">Socket</font>, <font color="#009900">Data</font>), + <b><font color="#000000">loop</font></b>(<font color="#009900">Socket</font>, <font color="#009900">Transport</font>); + <font color="#990000">_</font> <font color="#990000">-></font> + <font color="#0000FF">ok</font> <font color="#990000">=</font> <font color="#009900">Transport</font><font color="#990000">:</font><b><font color="#000000">close</font></b>(<font color="#009900">Socket</font>) + <b><font color="#0000FF">end</font></b><font color="#990000">.</font></tt></pre> +</div></div> +<h2 id="_using_gen_statem">Using gen_statem</h2> +<p>Special processes like the ones that use the <code>gen_statem</code> or <code>gen_server</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:handshake/1,2</code> from the <code>init</code> callback as this would cause a deadlock to happen.</p> +<p>Use the <code>gen_statem:enter_loop/4</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_statem</code> execution loop.</p> +<div class="listingblock"><div class="title">Use a gen_statem for protocol handling</div> +<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="#000080">-module</font></b>(<font color="#FF6600">my_protocol</font>)<font color="#990000">.</font> +<b><font color="#000080">-behaviour</font></b>(<font color="#FF6600">gen_statem</font>)<font color="#990000">.</font> +<b><font color="#000080">-behaviour</font></b>(<font color="#FF6600">ranch_protocol</font>)<font color="#990000">.</font> + +<b><font color="#000080">-export</font></b>([<b><font color="#000000">start_link</font></b><font color="#990000">/</font><font color="#993399">4</font>])<font color="#990000">.</font> +<b><font color="#000080">-export</font></b>([<b><font color="#000000">init</font></b><font color="#990000">/</font><font color="#993399">1</font>])<font color="#990000">.</font> +<i><font color="#9A1900">%% Exports of other gen_statem callbacks here.</font></i> + +<b><font color="#000000">start_link</font></b>(<font color="#009900">Ref</font>, <font color="#009900">_Socket</font>, <font color="#009900">Transport</font>, <font color="#009900">Opts</font>) <font color="#990000">-></font> + {<font color="#FF6600">ok</font>, <b><font color="#000000">proc_lib:spawn_link</font></b>(<b><font color="#000080">?MODULE</font></b>, <font color="#FF6600">init</font>, [{<font color="#009900">Ref</font>, <font color="#009900">Transport</font>, <font color="#009900">Opts</font>}])}<font color="#990000">.</font> + +<b><font color="#000000">init</font></b>({<font color="#009900">Ref</font>, <font color="#009900">Transport</font>, <font color="#009900">_Opts</font> <font color="#990000">=</font> []}) <font color="#990000">-></font> + <i><font color="#9A1900">%% Perform any required state initialization here.</font></i> + {<font color="#FF6600">ok</font>, <font color="#009900">Socket</font>} <font color="#990000">=</font> <b><font color="#000000">ranch:handshake</font></b>(<font color="#009900">Ref</font>), + <font color="#0000FF">ok</font> <font color="#990000">=</font> <font color="#009900">Transport</font><font color="#990000">:</font><b><font color="#000000">setopts</font></b>(<font color="#009900">Socket</font>, [{<font color="#FF6600">active</font>, <font color="#FF6600">once</font>}]), + <b><font color="#000000">gen_statem:enter_loop</font></b>(<b><font color="#000080">?MODULE</font></b>, [], <font color="#FF6600">state_name</font>, {<font color="#FF6600">state_data</font>, <font color="#009900">Socket</font>, <font color="#009900">Transport</font>})<font color="#990000">.</font> + +<i><font color="#9A1900">%% Other gen_statem callbacks here.</font></i></tt></pre> +</div></div> +<p>Check the <code>tcp_reverse</code> example for a complete example.</p> + + + + + + + + + + + + <nav style="margin:1em 0"> + + <a style="float:left" href="https://ninenines.eu/docs/en/ranch/1.8/guide/transports/"> + Transports + </a> + + + + <a style="float:right" href="https://ninenines.eu/docs/en/ranch/1.8/guide/embedded/"> + Embedded mode + </a> + + </nav> + + + + +</div> + +<div class="span3 sidecol"> + + +<h3> + Ranch + 1.8 + + User Guide +</h3> + +<ul> + + <li><a href="/docs/en/ranch/1.8/guide">User Guide</a></li> + + + <li><a href="/docs/en/ranch/1.8/manual">Function Reference</a></li> + + +</ul> + +<h4 id="docs-nav">Navigation</h4> + +<h4>Version select</h4> +<ul> + + + + <li><a href="/docs/en/ranch/2.0/guide">2.0</a></li> + + <li><a href="/docs/en/ranch/1.8/guide">1.8</a></li> + + <li><a href="/docs/en/ranch/1.7/guide">1.7</a></li> + + <li><a href="/docs/en/ranch/1.6/guide">1.6</a></li> + + <li><a href="/docs/en/ranch/1.5/guide">1.5</a></li> + +</ul> + +<h3 id="_like_my_work__donate">Like my work? 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