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diff --git a/rubbos/app/httpd-2.0.64/docs/manual/mod/mod_deflate.html.en b/rubbos/app/httpd-2.0.64/docs/manual/mod/mod_deflate.html.en new file mode 100644 index 00000000..c61f25a9 --- /dev/null +++ b/rubbos/app/httpd-2.0.64/docs/manual/mod/mod_deflate.html.en @@ -0,0 +1,356 @@ +<?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><!-- + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + This file is generated from xml source: DO NOT EDIT + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + --> +<title>mod_deflate - Apache HTTP Server</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 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="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p> +<p class="apache">Apache HTTP Server Version 2.0</p> +<img alt="" src="../images/feather.gif" /></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 2.0</a> > <a href="./">Modules</a></div> +<div id="page-content"> +<div id="preamble"><h1>Apache Module mod_deflate</h1> +<div class="toplang"> +<p><span>Available Languages: </span><a href="../en/mod/mod_deflate.html" title="English"> en </a> | +<a href="../ja/mod/mod_deflate.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="../ko/mod/mod_deflate.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>Compress content before it is delivered to the +client</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>deflate_module</td></tr> +<tr><th><a href="module-dict.html#SourceFile">Source File:</a></th><td>mod_deflate.c</td></tr></table> +<h3>Summary</h3> + + <p>The <code class="module"><a href="../mod/mod_deflate.html">mod_deflate</a></code> module provides + the <code>DEFLATE</code> output filter that allows output from + your server to be compressed before being sent to the client over + the network.</p> +</div> +<div id="quickview"><h3 class="directives">Directives</h3> +<ul id="toc"> +<li><img alt="" src="../images/down.gif" /> <a href="#deflatebuffersize">DeflateBufferSize</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#deflatecompressionlevel">DeflateCompressionLevel</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#deflatefilternote">DeflateFilterNote</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#deflatememlevel">DeflateMemLevel</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#deflatewindowsize">DeflateWindowSize</a></li> +</ul> +<h3>Topics</h3> +<ul id="topics"> +<li><img alt="" src="../images/down.gif" /> <a href="#recommended">Sample Configurations</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#enable">Enabling Compression</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#proxies">Dealing with proxy servers</a></li> +</ul><h3>See also</h3> +<ul class="seealso"> +<li><a href="../filter.html">Filters</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="recommended" id="recommended">Sample Configurations</a></h2> + <p>This is a simple sample configuration for the impatient.</p> + + <div class="example"><h3>Compress only a few types</h3><p><code> + AddOutputFilterByType DEFLATE text/html text/plain text/xml + </code></p></div> + + <p>The following configuration, while resulting in more compressed content, + is also much more complicated. Do not use this unless you fully understand + all the configuration details.</p> + + <div class="example"><h3>Compress everything except images</h3><p><code> + <Location /><br /> + <span class="indent"> + # Insert filter<br /> + SetOutputFilter DEFLATE<br /> + <br /> + # Netscape 4.x has some problems...<br /> + BrowserMatch ^Mozilla/4 gzip-only-text/html<br /> + <br /> + # Netscape 4.06-4.08 have some more problems<br /> + BrowserMatch ^Mozilla/4\.0[678] no-gzip<br /> + <br /> + # MSIE masquerades as Netscape, but it is fine<br /> + # BrowserMatch \bMSIE !no-gzip !gzip-only-text/html<br /> + <br /> + # NOTE: Due to a bug in mod_setenvif up to Apache 2.0.48<br /> + # the above regex won't work. You can use the following<br /> + # workaround to get the desired effect:<br /> + BrowserMatch \bMSI[E] !no-gzip !gzip-only-text/html<br /> + <br /> + # Don't compress images<br /> + SetEnvIfNoCase Request_URI \<br /> + <span class="indent"> + \.(?:gif|jpe?g|png)$ no-gzip dont-vary<br /> + </span> + <br /> + # Make sure proxies don't deliver the wrong content<br /> + Header append Vary User-Agent env=!dont-vary<br /> + </span> + </Location> + </code></p></div> + +</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="enable" id="enable">Enabling Compression</a></h2> + + <h3><a name="output" id="output">Output Compression</a></h3> + <p>Compression is implemented by the <code>DEFLATE</code> + <a href="../filter.html">filter</a>. The following directive + will enable compression for documents in the container where it + is placed:</p> + + <div class="example"><p><code> + SetOutputFilter DEFLATE + </code></p></div> + + <p>Some popular browsers cannot handle compression of all content + so you may want to set the <code>gzip-only-text/html</code> note to + <code>1</code> to only allow html files to be compressed (see + below). If you set this to <em>anything but <code>1</code></em> it + will be ignored.</p> + + <p>If you want to restrict the compression to particular MIME types + in general, you may use the <code class="directive"><a href="../mod/core.html#addoutputfilterbytype">AddOutputFilterByType</a></code> directive. Here is an example of + enabling compression only for the html files of the Apache + documentation:</p> + + <div class="example"><p><code> + <Directory "/your-server-root/manual"><br /> + <span class="indent"> + AddOutputFilterByType DEFLATE text/html<br /> + </span> + </Directory> + </code></p></div> + + <p>For browsers that have problems even with compression of all file + types, use the <code class="directive"><a href="../mod/mod_setenvif.html#browsermatch">BrowserMatch</a></code> directive to set the <code>no-gzip</code> + note for that particular browser so that no compression will be + performed. You may combine <code>no-gzip</code> with <code>gzip-only-text/html</code> to get the best results. In that case + the former overrides the latter. Take a look at the following + excerpt from the <a href="#recommended">configuration example</a> + defined in the section above:</p> + + <div class="example"><p><code> + BrowserMatch ^Mozilla/4 gzip-only-text/html<br /> + BrowserMatch ^Mozilla/4\.0[678] no-gzip<br /> + BrowserMatch \bMSIE !no-gzip !gzip-only-text/html + </code></p></div> + + <p>At first we probe for a <code>User-Agent</code> string that + indicates a Netscape Navigator version of 4.x. These versions + cannot handle compression of types other than + <code>text/html</code>. The versions 4.06, 4.07 and 4.08 also + have problems with decompressing html files. Thus, we completely + turn off the deflate filter for them.</p> + + <p>The third <code class="directive"><a href="../mod/mod_setenvif.html#browsermatch">BrowserMatch</a></code> + directive fixes the guessed identity of the user agent, because + the Microsoft Internet Explorer identifies itself also as "Mozilla/4" + but is actually able to handle requested compression. Therefore we + match against the additional string "MSIE" (<code>\b</code> means + "word boundary") in the <code>User-Agent</code> Header and turn off + the restrictions defined before.</p> + + <div class="note"><h3>Note</h3> + The <code>DEFLATE</code> filter is always inserted after RESOURCE + filters like PHP or SSI. It never touches internal subrequests. + </div> + + + <h3><a name="input" id="input">Input Decompression</a></h3> + <p>The <code class="module"><a href="../mod/mod_deflate.html">mod_deflate</a></code> module also provides a filter for + decompressing a gzip compressed request body . In order to activate + this feature you have to insert the <code>DEFLATE</code> filter into + the input filter chain using <code class="directive"><a href="../mod/core.html#setinputfilter">SetInputFilter</a></code> or <code class="directive"><a href="../mod/mod_mime.html#addinputfilter">AddInputFilter</a></code>, for example:</p> + + <div class="example"><p><code> + <Location /dav-area><br /> + <span class="indent"> + SetInputFilter DEFLATE<br /> + </span> + </Location> + </code></p></div> + + <p>Now if a request contains a <code>Content-Encoding: + gzip</code> header, the body will be automatically decompressed. + Few browsers have the ability to gzip request bodies. However, + some special applications actually do support request + compression, for instance some <a href="http://www.webdav.org">WebDAV</a> clients.</p> + + <div class="warning"><h3>Note on Content-Length</h3> + <p>If you evaluate the request body yourself, <em>don't trust + the <code>Content-Length</code> header!</em> + The Content-Length header reflects the length of the + incoming data from the client and <em>not</em> the byte count of + the decompressed data stream.</p> + </div> + +</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="proxies" id="proxies">Dealing with proxy servers</a></h2> + + <p>The <code class="module"><a href="../mod/mod_deflate.html">mod_deflate</a></code> module sends a <code>Vary: + Accept-Encoding</code> HTTP response header to alert proxies that + a cached response should be sent only to clients that send the + appropriate <code>Accept-Encoding</code> request header. This + prevents compressed content from being sent to a client that will + not understand it.</p> + + <p>If you use some special exclusions dependent + on, for example, the <code>User-Agent</code> header, you must + manually configure an addition to the <code>Vary</code> header + to alert proxies of the additional restrictions. For example, + in a typical configuration where the addition of the <code>DEFLATE</code> + filter depends on the <code>User-Agent</code>, you should add:</p> + + <div class="example"><p><code> + Header append Vary User-Agent + </code></p></div> + + <p>If your decision about compression depends on other information + than request headers (<em>e.g.</em> HTTP version), you have to set the + <code>Vary</code> header to the value <code>*</code>. This prevents + compliant proxies from caching entirely.</p> + + <div class="example"><h3>Example</h3><p><code> + Header set Vary * + </code></p></div> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="DeflateBufferSize" id="DeflateBufferSize">DeflateBufferSize</a> <a name="deflatebuffersize" id="deflatebuffersize">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Fragment size to be compressed at one time by zlib</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DeflateBufferSize <var>value</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>DeflateBufferSize 8096</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</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_deflate</td></tr> +</table> + <p>The <code class="directive">DeflateBufferSize</code> directive specifies + the size in bytes of the fragments that zlib should compress at one + time.</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="DeflateCompressionLevel" id="DeflateCompressionLevel">DeflateCompressionLevel</a> <a name="deflatecompressionlevel" id="deflatecompressionlevel">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>How much compression do we apply to the output</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DeflateCompressionLevel <var>value</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>Zlib's default</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</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_deflate</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td>This directive is available since Apache 2.0.45</td></tr> +</table> + <p>The <code class="directive">DeflateCompressionLevel</code> directive specifies + what level of compression should be used, the higher the value, + the better the compression, but the more CPU time is required to + achieve this.</p> + <p>The value must between 1 (less compression) and 9 (more compression).</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="DeflateFilterNote" id="DeflateFilterNote">DeflateFilterNote</a> <a name="deflatefilternote" id="deflatefilternote">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Places the compression ratio in a note for logging</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DeflateFilterNote [<var>type</var>] <var>notename</var></code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</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_deflate</td></tr> +<tr><th><a href="directive-dict.html#Compatibility">Compatibility:</a></th><td><var>type</var> is available since Apache 2.0.45</td></tr> +</table> + <p>The <code class="directive">DeflateFilterNote</code> directive + specifies that a note about compression ratios should be attached + to the request. The name of the note is the value specified for + the directive. You can use that note for statistical purposes by + adding the value to your <a href="../logs.html#accesslog">access log</a>.</p> + + <div class="example"><h3>Example</h3><p><code> + DeflateFilterNote ratio<br /> + <br /> + LogFormat '"%r" %b (%{ratio}n) "%{User-agent}i"' deflate<br /> + CustomLog logs/deflate_log deflate + </code></p></div> + + <p>If you want to extract more accurate values from your logs, you + can use the <var>type</var> argument to specify the type of data + left as note for logging. <var>type</var> can be one of:</p> + + <dl> + <dt><code>Input</code></dt> + <dd>Store the byte count of the filter's input stream in the note.</dd> + + <dt><code>Output</code></dt> + <dd>Store the byte count of the filter's output stream in the note.</dd> + + <dt><code>Ratio</code></dt> + <dd>Store the compression ratio (<code>output/input * 100</code>) + in the note. This is the default, if the <var>type</var> argument + is omitted.</dd> + </dl> + + <p>Thus you may log it this way:</p> + + <div class="example"><h3>Accurate Logging</h3><p><code> + DeflateFilterNote Input instream<br /> + DeflateFilterNote Output outstream<br /> + DeflateFilterNote Ratio ratio<br /> + <br /> + LogFormat '"%r" %{outstream}n/%{instream}n (%{ratio}n%%)' deflate<br /> + CustomLog logs/deflate_log deflate + </code></p></div> + +<h3>See also</h3> +<ul> +<li><code class="module"><a href="../mod/mod_log_config.html">mod_log_config</a></code></li> +</ul> +</div> +<div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="directive-section"><h2><a name="DeflateMemLevel" id="DeflateMemLevel">DeflateMemLevel</a> <a name="deflatememlevel" id="deflatememlevel">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>How much memory should be used by zlib for compression</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DeflateMemLevel <var>value</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>DeflateMemLevel 9</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</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_deflate</td></tr> +</table> + <p>The <code class="directive">DeflateMemLevel</code> directive specifies + how much memory should be used by zlib for compression + (a value between 1 and 9).</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="DeflateWindowSize" id="DeflateWindowSize">DeflateWindowSize</a> <a name="deflatewindowsize" id="deflatewindowsize">Directive</a></h2> +<table class="directive"> +<tr><th><a href="directive-dict.html#Description">Description:</a></th><td>Zlib compression window size</td></tr> +<tr><th><a href="directive-dict.html#Syntax">Syntax:</a></th><td><code>DeflateWindowSize <var>value</var></code></td></tr> +<tr><th><a href="directive-dict.html#Default">Default:</a></th><td><code>DeflateWindowSize 15</code></td></tr> +<tr><th><a href="directive-dict.html#Context">Context:</a></th><td>server config, virtual host</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_deflate</td></tr> +</table> + <p>The <code class="directive">DeflateWindowSize</code> directive specifies the + zlib compression window size (a value between 1 and 15). Generally, the + higher the window size, the higher can the compression ratio be expected.</p> + +</div> +</div> +<div class="bottomlang"> +<p><span>Available Languages: </span><a href="../en/mod/mod_deflate.html" title="English"> en </a> | +<a href="../ja/mod/mod_deflate.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="../ko/mod/mod_deflate.html" hreflang="ko" rel="alternate" title="Korean"> ko </a></p> +</div><div id="footer"> +<p class="apache">Copyright 2009 The Apache Software Foundation.<br />Licensed under the <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache License, Version 2.0</a>.</p> +<p class="menu"><a href="../mod/">Modules</a> | <a href="../mod/directives.html">Directives</a> | <a href="../faq/">FAQ</a> | <a href="../glossary.html">Glossary</a> | <a href="../sitemap.html">Sitemap</a></p></div> +</body></html>
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