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diff --git a/docs/manual/mod/mod_expires.html.en b/docs/manual/mod/mod_expires.html.en new file mode 100644 index 0000000..5b07eba --- /dev/null +++ b/docs/manual/mod/mod_expires.html.en @@ -0,0 +1,274 @@ +<?xml version="1.0" encoding="ISO-8859-1"?> +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"><head> +<meta content="text/html; charset=ISO-8859-1" http-equiv="Content-Type" /> +<!-- + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + This file is generated from xml source: DO NOT EDIT + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + --> +<title>mod_expires - Apache HTTP Server Version 2.4</title> +<link href="../style/css/manual.css" rel="stylesheet" media="all" type="text/css" title="Main stylesheet" /> +<link href="../style/css/manual-loose-100pc.css" rel="alternate stylesheet" media="all" type="text/css" title="No Sidebar - Default font size" /> +<link href="../style/css/manual-print.css" rel="stylesheet" media="print" type="text/css" /><link rel="stylesheet" type="text/css" href="../style/css/prettify.css" /> +<script src="../style/scripts/prettify.min.js" type="text/javascript"> +</script> + +<link href="../images/favicon.ico" rel="shortcut icon" /></head> +<body> +<div id="page-header"> +<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p> +<p class="apache">Apache HTTP Server Version 2.4</p> +<img alt="" src="../images/feather.png" /></div> +<div class="up"><a href="./"><img title="<-" alt="<-" src="../images/left.gif" /></a></div> +<div id="path"> +<a href="http://www.apache.org/">Apache</a> > <a href="http://httpd.apache.org/">HTTP Server</a> > <a href="http://httpd.apache.org/docs/">Documentation</a> > <a href="../">Version 2.4</a> > <a href="./">Modules</a></div> +<div id="page-content"> +<div id="preamble"><h1>Apache Module mod_expires</h1> +<div class="toplang"> +<p><span>Available Languages: </span><a href="../en/mod/mod_expires.html" title="English"> en </a> | +<a href="../fr/mod/mod_expires.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="../ja/mod/mod_expires.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="../ko/mod/mod_expires.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p> +</div> +<table class="module"><tr><th><a href="module-dict.html#Description">Description:</a></th><td>Generation of <code>Expires</code> and +<code>Cache-Control</code> HTTP headers according to user-specified +criteria</td></tr> +<tr><th><a href="module-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="module-dict.html#ModuleIdentifier">Module Identifier:</a></th><td>expires_module</td></tr> +<tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_expires.c</td></tr></table> +<h3>Summary</h3> + + <p>This module controls the setting of the <code>Expires</code> + HTTP header and the <code>max-age</code> directive of the + <code>Cache-Control</code> HTTP header in server responses. The + expiration date can set to be relative to either the time the + source file was last modified, or to the time of the client + access.</p> + + <p>These HTTP headers are an instruction to the client about the + document's validity and persistence. If cached, the document may + be fetched from the cache rather than from the source until this + time has passed. After that, the cache copy is considered + "expired" and invalid, and a new copy must be obtained from the + source.</p> + + <p>To modify <code>Cache-Control</code> directives other than + <code>max-age</code> (see <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.9">RFC + 2616 section 14.9</a>), you can use the <code class="directive"><a href="../mod/mod_headers.html#header">Header</a></code> directive.</p> + + <p> When the <code>Expires</code> header is already part of the response + generated by the server, for example when generated by a CGI script or + proxied from an origin server, this module does not change or add + an <code>Expires</code> or <code>Cache-Control</code> header.</p> +</div> +<div id="quickview"><a href="https://www.apache.org/foundation/contributing.html" class="badge"><img src="https://www.apache.org/images/SupportApache-small.png" alt="Support Apache!" /></a><h3>Topics</h3> +<ul id="topics"> +<li><img alt="" src="../images/down.gif" /> <a href="#AltSyn">Alternate Interval Syntax</a></li> +</ul><h3 class="directives">Directives</h3> +<ul id="toc"> +<li><img alt="" src="../images/down.gif" /> <a href="#expiresactive">ExpiresActive</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#expiresbytype">ExpiresByType</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#expiresdefault">ExpiresDefault</a></li> +</ul> +<h3>Bugfix checklist</h3><ul class="seealso"><li><a href="https://www.apache.org/dist/httpd/CHANGES_2.4">httpd changelog</a></li><li><a href="https://bz.apache.org/bugzilla/buglist.cgi?bug_status=__open__&list_id=144532&product=Apache%20httpd-2&query_format=specific&order=changeddate%20DESC%2Cpriority%2Cbug_severity&component=mod_expires">Known issues</a></li><li><a href="https://bz.apache.org/bugzilla/enter_bug.cgi?product=Apache%20httpd-2&component=mod_expires">Report a bug</a></li></ul><h3>See also</h3> +<ul class="seealso"> +<li><a href="#comments_section">Comments</a></li></ul></div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="AltSyn" id="AltSyn">Alternate Interval Syntax</a></h2> + <p>The <code class="directive"><a href="#expiresdefault">ExpiresDefault</a></code> and + <code class="directive"><a href="#expiresbytype">ExpiresByType</a></code> directives + can also be defined in a more readable syntax of the form:</p> + + <pre class="prettyprint lang-config">ExpiresDefault "<var>base</var> [plus <var>num</var> <var>type</var>] [<var>num</var> <var>type</var>] ..." +ExpiresByType type/encoding "<var>base</var> [plus <var>num</var> <var>type</var>] [<var>num</var> <var>type</var>] ..."</pre> + + + <p>where <var>base</var> is one of:</p> + + <ul> + <li><code>access</code></li> + + <li><code>now</code> (equivalent to + '<code>access</code>')</li> + + <li><code>modification</code></li> + </ul> + + <p>The <code>plus</code> keyword is optional. <var>num</var> + should be an integer value [acceptable to <code>atoi()</code>], + and <var>type</var> is one of:</p> + + <ul> + <li><code>years</code></li> + <li><code>months</code></li> + <li><code>weeks</code></li> + <li><code>days</code></li> + <li><code>hours</code></li> + <li><code>minutes</code></li> + <li><code>seconds</code></li> + </ul> + + <p>For example, any of the following directives can be used to + make documents expire 1 month after being accessed, by + default:</p> + + <pre class="prettyprint lang-config">ExpiresDefault "access plus 1 month" +ExpiresDefault "access plus 4 weeks" +ExpiresDefault "access plus 30 days"</pre> + + + <p>The expiry time can be fine-tuned by adding several + '<var>num</var> <var>type</var>' clauses:</p> + + <pre class="prettyprint lang-config">ExpiresByType text/html "access plus 1 month 15 days 2 hours" +ExpiresByType image/gif "modification plus 5 hours 3 minutes"</pre> + + + <p>Note that if you use a modification date based setting, the + Expires header will <strong>not</strong> be added to content + that does not come from a file on disk. This is due to the fact + that there is no modification time for such content.</p> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ExpiresActive" id="ExpiresActive">ExpiresActive</a> <a name="expiresactive" id="expiresactive">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Enables generation of <code>Expires</code> +headers</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ExpiresActive On|Off</code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>ExpiresActive Off</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Indexes</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_expires</td></tr> +</table> + <p>This directive enables or disables the generation of the + <code>Expires</code> and <code>Cache-Control</code> headers for + the document realm in question. (That is, if found in an + <code>.htaccess</code> file, for instance, it applies only to + documents generated from that directory.) If set to + <code>Off</code>, the headers will not be generated for any + document in the realm (unless overridden at a lower level, such as + an <code>.htaccess</code> file overriding a server config + file). If set to <code>On</code>, the headers will be added to + served documents according to the criteria defined by the + <code class="directive"><a href="#expiresbytype">ExpiresByType</a></code> and + <code class="directive"><a href="#expiresdefault">ExpiresDefault</a></code> + directives (<em>q.v.</em>).</p> + + <p>Note that this directive does not guarantee that an + <code>Expires</code> or <code>Cache-Control</code> header will be + generated. If the criteria aren't met, no header will be sent, and + the effect will be as though this directive wasn't even + specified.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ExpiresByType" id="ExpiresByType">ExpiresByType</a> <a name="expiresbytype" id="expiresbytype">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Value of the <code>Expires</code> header configured +by MIME type</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ExpiresByType <var>MIME-type</var> +<var><code>seconds</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Indexes</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_expires</td></tr> +</table> + <p>This directive defines the value of the <code>Expires</code> + header and the <code>max-age</code> directive of the + <code>Cache-Control</code> header generated for documents of the + specified type (<em>e.g.</em>, <code>text/html</code>). The second + argument sets the number of seconds that will be added to a base + time to construct the expiration date. The <code>Cache-Control: + max-age</code> is calculated by subtracting the request time from + the expiration date and expressing the result in seconds.</p> + + <p>The base time is either the last modification time of the + file, or the time of the client's access to the document. Which + should be used is specified by the + <code><var><code></var></code> field; <code>M</code> + means that the file's last modification time should be used as + the base time, and <code>A</code> means the client's access + time should be used.</p> + + <p>The difference in effect is subtle. If <code>M</code> is used, + all current copies of the document in all caches will expire at + the same time, which can be good for something like a weekly + notice that's always found at the same URL. If <code>A</code> is + used, the date of expiration is different for each client; this + can be good for image files that don't change very often, + particularly for a set of related documents that all refer to + the same images (<em>i.e.</em>, the images will be accessed + repeatedly within a relatively short timespan).</p> + + <div class="example"><h3>Example:</h3><pre class="prettyprint lang-config"># enable expirations +ExpiresActive On +# expire GIF images after a month in the client's cache +ExpiresByType image/gif A2592000 +# HTML documents are good for a week from the +# time they were changed +ExpiresByType text/html M604800</pre> +</div> + + <p>Note that this directive only has effect if + <code>ExpiresActive On</code> has been specified. It overrides, + for the specified MIME type <em>only</em>, any expiration date + set by the <code class="directive"><a href="#expiresdefault">ExpiresDefault</a></code> + directive.</p> + + <p>You can also specify the expiration time calculation using + an <a href="#AltSyn">alternate syntax</a>, described earlier in + this document.</p> + +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="ExpiresDefault" id="ExpiresDefault">ExpiresDefault</a> <a name="expiresdefault" id="expiresdefault">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Default algorithm for calculating expiration time</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>ExpiresDefault <var><code>seconds</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host, directory, .htaccess</td></tr> +<tr><th><a href="directive-dict.html#Override">Override:</a></th><td>Indexes</td></tr> +<tr><th><a href="directive-dict.html#Status">Status:</a></th><td>Extension</td></tr> +<tr><th><a href="directive-dict.html#Module">Module:</a></th><td>mod_expires</td></tr> +</table> + <p>This directive sets the default algorithm for calculating the + expiration time for all documents in the affected realm. It can be + overridden on a type-by-type basis by the <code class="directive"><a href="#expiresbytype">ExpiresByType</a></code> directive. See the + description of that directive for details about the syntax of the + argument, and the <a href="#AltSyn">alternate syntax</a> + description as well.</p> + +</div> +</div> +<div class="bottomlang"> +<p><span>Available Languages: </span><a href="../en/mod/mod_expires.html" title="English"> en </a> | +<a href="../fr/mod/mod_expires.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="../ja/mod/mod_expires.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="../ko/mod/mod_expires.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p> +</div><div class="top"><a href="#page-header"><img src="../images/up.gif" alt="top" /></a></div><div class="section"><h2><a id="comments_section" name="comments_section">Comments</a></h2><div class="warning"><strong>Notice:</strong><br />This is not a Q&A section. 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