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diff --git a/docs/en/gun/2.1/guide/websocket/index.html b/docs/en/gun/2.1/guide/websocket/index.html new file mode 100644 index 00000000..cf154726 --- /dev/null +++ b/docs/en/gun/2.1/guide/websocket/index.html @@ -0,0 +1,264 @@ +<!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: Websocket</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>Websocket</span></h1> + +<p>This chapter describes how to use the Gun client for communicating with a Websocket server.</p> +<!-- @todo recovering from connection failure, reconnecting to Websocket etc.--> +<h2 id="_http_upgrade">HTTP upgrade</h2> +<p>Websocket is a protocol built on top of HTTP. To use Websocket, you must first request for the connection to be upgraded. Only HTTP/1.1 connections can be upgraded to Websocket, so you might need to restrict the protocol to HTTP/1.1 if you are planning to use Websocket over TLS.</p> +<p>You must use the <code>gun:ws_upgrade/2,3,4</code> function to upgrade to Websocket. This function can be called anytime after connection, so you can send HTTP requests before upgrading to Websocket.</p> +<div class="listingblock"><div class="title">Upgrade to Websocket</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="#000000">gun:ws_upgrade</font></b>(<font color="#009900">ConnPid</font>, <font color="#FF0000">"/websocket"</font>)<font color="#990000">.</font></tt></pre> +</div></div> +<p>Gun will set all the necessary headers for performing the Websocket upgrade, but you can specify additional headers if needed. For example you can authenticate.</p> +<div class="listingblock"><div class="title">Upgrade to Websocket using HTTP authentication</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="#000000">gun:ws_upgrade</font></b>(<font color="#009900">ConnPid</font>, <font color="#FF0000">"/websocket"</font>, [ + {<font color="#990000"><<</font><font color="#FF0000">"authorization"</font><font color="#990000">>></font>, <font color="#FF0000">"Basic dXNlcm5hbWU6cGFzc3dvcmQ="</font>} +])<font color="#990000">.</font></tt></pre> +</div></div> +<p>You can pass the Websocket options as part of the <code>gun:open/2,3</code> call when opening the connection, or using the <code>gun:ws_upgrade/4</code>. The fourth argument is those same options.</p> +<p>Gun can negotiate the protocol to be used for the Websocket connection. The <code>protocols</code> option can be given with a list of protocols accepted and the corresponding handler module. Note that the interface for handler modules is currently undocumented and must be set to <code>gun_ws_h</code>.</p> +<div class="listingblock"><div class="title">Upgrade to Websocket with protocol negotiation</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="#009900">StreamRef</font> <font color="#990000">=</font> <b><font color="#000000">gun:ws_upgrade</font></b>(<font color="#009900">ConnPid</font>, <font color="#FF0000">"/websocket"</font>, [] + #{<font color="#0000FF">protocols</font> <font color="#990000">=></font> [{<font color="#990000"><<</font><font color="#FF0000">"xmpp"</font><font color="#990000">>></font>, <font color="#FF6600">gun_ws_h</font>}]})<font color="#990000">.</font></tt></pre> +</div></div> +<p>The upgrade will fail if the server cannot satisfy the protocol negotiation.</p> +<p>When the upgrade succeeds, a <code>gun_upgrade</code> message is sent. If the server does not understand Websocket or refused the upgrade, a <code>gun_response</code> message is sent. If Gun couldn't perform the upgrade due to an error (for example attempting to upgrade to Websocket on an HTTP/1.0 connection) then a <code>gun_error</code> message is sent.</p> +<p>When the server does not understand Websocket, it may send a meaningful response which should be processed. In the following example we however ignore it:</p> +<div class="listingblock"><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="#0000FF">receive</font></b> + {<font color="#FF6600">gun_upgrade</font>, <font color="#009900">ConnPid</font>, <font color="#009900">StreamRef</font>, [<font color="#990000"><<</font><font color="#FF0000">"websocket"</font><font color="#990000">>></font>], <font color="#009900">Headers</font>} <font color="#990000">-></font> + <b><font color="#000000">upgrade_success</font></b>(<font color="#009900">ConnPid</font>, <font color="#009900">StreamRef</font>); + {<font color="#FF6600">gun_response</font>, <font color="#009900">ConnPid</font>, <font color="#990000">_</font>, <font color="#990000">_</font>, <font color="#009900">Status</font>, <font color="#009900">Headers</font>} <font color="#990000">-></font> + <b><font color="#000080">exit</font></b>({<font color="#FF6600">ws_upgrade_failed</font>, <font color="#009900">Status</font>, <font color="#009900">Headers</font>}); + {<font color="#FF6600">gun_error</font>, <font color="#009900">ConnPid</font>, <font color="#009900">StreamRef</font>, <font color="#009900">Reason</font>} <font color="#990000">-></font> + <b><font color="#000080">exit</font></b>({<font color="#FF6600">ws_upgrade_failed</font>, <font color="#009900">Reason</font>}) + <i><font color="#9A1900">%% More clauses here as needed.</font></i> +<b><font color="#0000FF">after</font></b> <font color="#993399">1000</font> <font color="#990000">-></font> + <b><font color="#000080">exit</font></b>(<font color="#FF6600">timeout</font>) +<b><font color="#0000FF">end</font></b><font color="#990000">.</font></tt></pre> +</div></div> +<h2 id="_sending_data">Sending data</h2> +<p>Once the Websocket upgrade has completed successfully, you no longer have access to functions for performing requests. You can only send and receive Websocket messages.</p> +<p>Use <code>gun:ws_send/3</code> to send messages to the server.</p> +<div class="listingblock"><div class="title">Send a text frame</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="#000000">gun:ws_send</font></b>(<font color="#009900">ConnPid</font>, <font color="#009900">StreamRef</font>, {<font color="#FF6600">text</font>, <font color="#FF0000">"Hello!"</font>})<font color="#990000">.</font></tt></pre> +</div></div> +<div class="listingblock"><div class="title">Send a text frame, a binary frame and then close the connection</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="#000000">gun:ws_send</font></b>(<font color="#009900">ConnPid</font>, <font color="#009900">StreamRef</font>, [ + {<font color="#FF6600">text</font>, <font color="#FF0000">"Hello!"</font>}, + {<b><font color="#000080">binary</font></b>, <font color="#009900">BinaryValue</font>}, + <font color="#FF6600">close</font> +])<font color="#990000">.</font></tt></pre> +</div></div> +<p>Note that if you send a close frame, Gun will close the connection cleanly but may attempt to reconnect afterwards depending on the <code>retry</code> configuration.</p> +<h2 id="_receiving_data">Receiving data</h2> +<p>Gun sends an Erlang message to the owner process for every Websocket message it receives.</p> +<div class="listingblock"><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="#0000FF">receive</font></b> + {<font color="#FF6600">gun_ws</font>, <font color="#009900">ConnPid</font>, <font color="#009900">StreamRef</font>, <font color="#009900">Frame</font>} <font color="#990000">-></font> + <b><font color="#000000">handle_frame</font></b>(<font color="#009900">ConnPid</font>, <font color="#009900">StreamRef</font>, <font color="#009900">Frame</font>) +<b><font color="#0000FF">end</font></b><font color="#990000">.</font></tt></pre> +</div></div> + + + + + + + + + + + + <nav style="margin:1em 0"> + + <a style="float:left" href="https://ninenines.eu/docs/en/gun/2.1/guide/http/"> + HTTP + </a> + + + + <a style="float:right" href="https://ninenines.eu/docs/en/gun/2.1/guide/internals_tls_over_tls/"> + Internals: TLS over TLS + </a> + + </nav> + + + + +</div> + +<div class="span3 sidecol"> + + +<h3> + Gun + 2.1 + + User Guide +</h3> + +<ul> + + <li><a href="/docs/en/gun/2.1/guide">User Guide</a></li> + + + <li><a href="/docs/en/gun/2.1/manual">Function Reference</a></li> + + +</ul> + +<h4 id="docs-nav">Navigation</h4> + +<h4>Version select</h4> +<ul> + + + + <li><a href="/docs/en/gun/2.1/guide">2.1</a></li> + + <li><a href="/docs/en/gun/2.0/guide">2.0</a></li> + + <li><a href="/docs/en/gun/1.3/guide">1.3</a></li> + + <li><a href="/docs/en/gun/1.2/guide">1.2</a></li> + + <li><a href="/docs/en/gun/1.1/guide">1.1</a></li> + + <li><a href="/docs/en/gun/1.0/guide">1.0</a></li> + +</ul> + +<h3 id="_like_my_work__donate">Like my work? 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