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diff --git a/docs/en/ranch/1.4/guide/transports/index.html b/docs/en/ranch/1.4/guide/transports/index.html new file mode 100644 index 00000000..fe8da963 --- /dev/null +++ b/docs/en/ranch/1.4/guide/transports/index.html @@ -0,0 +1,336 @@ +<!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: Transports</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>Transports</span></h1> + +<div class="paragraph"><p>A transport defines the interface to interact with a socket.</p></div> +<div class="paragraph"><p>Transports can be used for connecting, listening and accepting +connections, but also for receiving and sending data. Both +passive and active mode are supported, although all sockets +are initialized as passive.</p></div> +<div class="sect1"> +<h2 id="_tcp_transport">TCP transport</h2> +<div class="sectionbody"> +<div class="paragraph"><p>The TCP transport is a thin wrapper around <code>gen_tcp</code>.</p></div> +</div> +</div> +<div class="sect1"> +<h2 id="_ssl_transport">SSL transport</h2> +<div class="sectionbody"> +<div class="paragraph"><p>The SSL transport is a thin wrapper around <code>ssl</code>.</p></div> +<div class="paragraph"><p>Ranch depends on <code>ssl</code> by default so any necessary +dependencies will start when Ranch is started. It is +possible to remove the dependency when the SSL transport +will not be used. Refer to your release build tool’s +documentation for more information.</p></div> +<div class="paragraph"><p>When embedding Ranch listeners that have an SSL transport, +your application must depend on the <code>ssl</code> application for +proper behavior.</p></div> +</div> +</div> +<div class="sect1"> +<h2 id="_sending_and_receiving_data">Sending and receiving data</h2> +<div class="sectionbody"> +<div class="paragraph"><p>This section assumes that <code>Transport</code> is a valid transport handler +(like <code>ranch_tcp</code> or <code>ranch_ssl</code>) and <code>Socket</code> is a connected +socket obtained through the listener.</p></div> +<div class="paragraph"><p>You can send data to a socket by calling the <code>Transport:send/2</code> +function. The data can be given as <code>iodata()</code>, which is defined as +<code>binary() | iolist()</code>. All the following calls will work:</p></div> +<div class="listingblock"> +<div class="title">Sending data to 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: #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: #990000"><<</span><span style="color: #FF0000">"Ranch is cool!"</span><span style="color: #990000">>></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: #FF0000">"Ranch is cool!"</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: #FF0000">"Ranch"</span>, [<span style="color: #FF0000">"is"</span>, <span style="color: #FF0000">"cool!"</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: #FF0000">"Ranch"</span>, [<span style="color: #990000"><<</span><span style="color: #FF0000">"is"</span><span style="color: #990000">>></span>, <span style="color: #FF0000">"cool!"</span>]])<span style="color: #990000">.</span></tt></pre></div></div> +<div class="paragraph"><p>You can receive data either in passive or in active mode. Passive mode +means that you will perform a blocking <code>Transport:recv/3</code> call, while +active mode means that you will receive the data as a message.</p></div> +<div class="paragraph"><p>By default, all data will be received as binary. It is possible to +receive data as strings, although this is not recommended as binaries +are a more efficient construct, especially for binary protocols.</p></div> +<div class="paragraph"><p>Receiving data using passive mode requires a single function call. The +first argument is the socket, and the third argument is a timeout duration +before the call returns with <code>{error, timeout}</code>.</p></div> +<div class="paragraph"><p>The second argument is the amount of data in bytes that we want to receive. +The function will wait for data until it has received exactly this amount. +If you are not expecting a precise size, you can specify 0 which will make +this call return as soon as data was read, regardless of its size.</p></div> +<div class="listingblock"> +<div class="title">Receiving data from the socket in passive mode</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: #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">recv</span></span>(<span style="color: #009900">Socket</span>, <span style="color: #993399">0</span>, <span style="color: #993399">5000</span>)<span style="color: #990000">.</span></tt></pre></div></div> +<div class="paragraph"><p>Active mode requires you to inform the socket that you want to receive +data as a message and to write the code to actually receive it.</p></div> +<div class="paragraph"><p>There are two kinds of active modes: <code>{active, once}</code> and +<code>{active, true}</code>. The first will send a single message before going +back to passive mode; the second will send messages indefinitely. +We recommend not using the <code>{active, true}</code> mode as it could quickly +flood your process mailbox. It’s better to keep the data in the socket +and read it only when required.</p></div> +<div class="paragraph"><p>Three different messages can be received:</p></div> +<div class="ulist"><ul> +<li> +<p> +<code>{OK, Socket, Data}</code> +</p> +</li> +<li> +<p> +<code>{Closed, Socket}</code> +</p> +</li> +<li> +<p> +<code>{Error, Socket, Reason}</code> +</p> +</li> +</ul></div> +<div class="paragraph"><p>The value of <code>OK</code>, <code>Closed</code> and <code>Error</code> can be different +depending on the transport being used. To be able to properly match +on them you must first call the <code>Transport:messages/0</code> function.</p></div> +<div class="listingblock"> +<div class="title">Retrieving the transport’s active message identifiers</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: #009900">OK</span>, <span style="color: #009900">Closed</span>, <span style="color: #009900">Error</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">messages</span></span>()<span style="color: #990000">.</span></tt></pre></div></div> +<div class="paragraph"><p>To start receiving messages you will need to call the <code>Transport:setopts/2</code> +function, and do so every time you want to receive data.</p></div> +<div class="listingblock"> +<div class="title">Receiving messages from the socket in active mode</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: #009900">OK</span>, <span style="color: #009900">Closed</span>, <span style="color: #009900">Error</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">messages</span></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: #0000FF">receive</span></span> + {<span style="color: #009900">OK</span>, <span style="color: #009900">Socket</span>, <span style="color: #009900">Data</span>} <span style="color: #990000">-></span> + <span style="font-weight: bold"><span style="color: #000000">io:format</span></span>(<span style="color: #FF0000">"data received: ~p~n"</span>, [<span style="color: #009900">Data</span>]); + {<span style="color: #009900">Closed</span>, <span style="color: #009900">Socket</span>} <span style="color: #990000">-></span> + <span style="font-weight: bold"><span style="color: #000000">io:format</span></span>(<span style="color: #FF0000">"socket got closed!~n"</span>); + {<span style="color: #009900">Error</span>, <span style="color: #009900">Socket</span>, <span style="color: #009900">Reason</span>} <span style="color: #990000">-></span> + <span style="font-weight: bold"><span style="color: #000000">io:format</span></span>(<span style="color: #FF0000">"error happened: ~p~n"</span>, [<span style="color: #009900">Reason</span>]) +<span style="font-weight: bold"><span style="color: #0000FF">end</span></span><span style="color: #990000">.</span></tt></pre></div></div> +<div class="paragraph"><p>You can easily integrate active sockets with existing Erlang code as all +you really need is just a few more clauses when receiving messages.</p></div> +</div> +</div> +<div class="sect1"> +<h2 id="_sending_files">Sending files</h2> +<div class="sectionbody"> +<div class="paragraph"><p>As in the previous section it is assumed <code>Transport</code> is a valid transport +handler and <code>Socket</code> is a connected socket obtained through the listener.</p></div> +<div class="paragraph"><p>To send a whole file, with name <code>Filename</code>, over a socket:</p></div> +<div class="listingblock"> +<div class="title">Sending a file by filename</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: #FF6600">ok</span>, <span style="color: #009900">SentBytes</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">sendfile</span></span>(<span style="color: #009900">Socket</span>, <span style="color: #009900">Filename</span>)<span style="color: #990000">.</span></tt></pre></div></div> +<div class="paragraph"><p>Or part of a file, with <code>Offset</code> greater than or equal to 0, <code>Bytes</code> number of +bytes and chunks of size <code>ChunkSize</code>:</p></div> +<div class="listingblock"> +<div class="title">Sending part of a file by filename in chunks</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: #009900">Opts</span> <span style="color: #990000">=</span> [{<span style="color: #FF6600">chunk_size</span>, <span style="color: #009900">ChunkSize</span>}], +{<span style="color: #FF6600">ok</span>, <span style="color: #009900">SentBytes</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">sendfile</span></span>(<span style="color: #009900">Socket</span>, <span style="color: #009900">Filename</span>, <span style="color: #009900">Offset</span>, <span style="color: #009900">Bytes</span>, <span style="color: #009900">Opts</span>)<span style="color: #990000">.</span></tt></pre></div></div> +<div class="paragraph"><p>To improve efficiency when sending multiple parts of the same file it is also +possible to use a file descriptor opened in raw mode:</p></div> +<div class="listingblock"> +<div class="title">Sending a file opened in raw mode</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: #FF6600">ok</span>, <span style="color: #009900">RawFile</span>} <span style="color: #990000">=</span> <span style="font-weight: bold"><span style="color: #000000">file:open</span></span>(<span style="color: #009900">Filename</span>, [<span style="color: #FF6600">raw</span>, <span style="color: #FF6600">read</span>, <span style="font-weight: bold"><span style="color: #000080">binary</span></span>]), +{<span style="color: #FF6600">ok</span>, <span style="color: #009900">SentBytes</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">sendfile</span></span>(<span style="color: #009900">Socket</span>, <span style="color: #009900">RawFile</span>, <span style="color: #009900">Offset</span>, <span style="color: #009900">Bytes</span>, <span style="color: #009900">Opts</span>)<span style="color: #990000">.</span></tt></pre></div></div> +</div> +</div> +<div class="sect1"> +<h2 id="_writing_a_transport_handler">Writing a transport handler</h2> +<div class="sectionbody"> +<div class="paragraph"><p>A transport handler is a module implementing the <code>ranch_transport</code> behavior. +It defines a certain number of callbacks that must be written in order to +allow transparent usage of the transport handler.</p></div> +<div class="paragraph"><p>The behavior doesn’t define the socket options available when opening a +socket. These do not need to be common to all transports as it’s easy enough +to write different initialization functions for the different transports that +will be used. With one exception though. The <code>setopts/2</code> function <strong>must</strong> +implement the <code>{active, once}</code> and the <code>{active, true}</code> options.</p></div> +<div class="paragraph"><p>If the transport handler doesn’t have a native implementation of <code>sendfile/5</code> a +fallback is available, <code>ranch_transport:sendfile/6</code>. The extra first argument +is the transport’s module. See <code>ranch_ssl</code> for an example.</p></div> +</div> +</div> + + + + + + + + + + + <nav style="margin:1em 0"> + + <a style="float:left" href="https://ninenines.eu/docs/en/ranch/1.4/guide/listeners/"> + Listeners + </a> + + + + <a style="float:right" href="https://ninenines.eu/docs/en/ranch/1.4/guide/protocols/"> + Protocols + </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 href="/docs/en/ranch/1.2/guide">1.2</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> + + |