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diff --git a/docs/manual/filter.html.en b/docs/manual/filter.html.en new file mode 100644 index 0000000..1185e62 --- /dev/null +++ b/docs/manual/filter.html.en @@ -0,0 +1,183 @@ +<?xml version="1.0" encoding="UTF-8"?> +<!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=UTF-8" http-equiv="Content-Type" /> +<!-- + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + This file is generated from xml source: DO NOT EDIT + XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX + --> +<title>Filters - 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 id="manual-page"><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></div><div id="page-content"><div id="preamble"><h1>Filters</h1> +<div class="toplang"> +<p><span>Available Languages: </span><a href="./en/filter.html" title="English"> en </a> | +<a href="./es/filter.html" hreflang="es" rel="alternate" title="Español"> es </a> | +<a href="./fr/filter.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="./ja/filter.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="./ko/filter.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | +<a href="./tr/filter.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </a></p> +</div> + + <p>This document describes the use of filters in Apache.</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><ul id="toc"><li><img alt="" src="./images/down.gif" /> <a href="#intro">Filtering in Apache 2</a></li> +<li><img alt="" src="./images/down.gif" /> <a href="#smart">Smart Filtering</a></li> +<li><img alt="" src="./images/down.gif" /> <a href="#service">Exposing Filters as an HTTP Service</a></li> +<li><img alt="" src="./images/down.gif" /> <a href="#using">Using Filters</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="intro" id="intro">Filtering in Apache 2</a></h2> + + <table class="related"><tr><th>Related Modules</th><th>Related Directives</th></tr><tr><td><ul><li><code class="module"><a href="./mod/mod_filter.html">mod_filter</a></code></li><li><code class="module"><a href="./mod/mod_deflate.html">mod_deflate</a></code></li><li><code class="module"><a href="./mod/mod_ext_filter.html">mod_ext_filter</a></code></li><li><code class="module"><a href="./mod/mod_include.html">mod_include</a></code></li><li><code class="module"><a href="./mod/mod_charset_lite.html">mod_charset_lite</a></code></li><li><code class="module"><a href="./mod/mod_reflector.html">mod_reflector</a></code></li><li><code class="module"><a href="./mod/mod_buffer.html">mod_buffer</a></code></li><li><code class="module"><a href="./mod/mod_data.html">mod_data</a></code></li><li><code class="module"><a href="./mod/mod_ratelimit.html">mod_ratelimit</a></code></li><li><code class="module"><a href="./mod/mod_reqtimeout.html">mod_reqtimeout</a></code></li><li><code class="module"><a href="./mod/mod_request.html">mod_request</a></code></li><li><code class="module"><a href="./mod/mod_sed.html">mod_sed</a></code></li><li><code class="module"><a href="./mod/mod_substitute.html">mod_substitute</a></code></li><li><code class="module"><a href="./mod/mod_xml2enc.html">mod_xml2enc</a></code></li><li><code class="module"><a href="./mod/mod_proxy_html.html">mod_proxy_html</a></code></li></ul></td><td><ul><li><code class="directive"><a href="./mod/mod_filter.html#filterchain">FilterChain</a></code></li><li><code class="directive"><a href="./mod/mod_filter.html#filterdeclare">FilterDeclare</a></code></li><li><code class="directive"><a href="./mod/mod_filter.html#filterprotocol">FilterProtocol</a></code></li><li><code class="directive"><a href="./mod/mod_filter.html#filterprovider">FilterProvider</a></code></li><li><code class="directive"><a href="./mod/mod_mime.html#addinputfilter">AddInputFilter</a></code></li><li><code class="directive"><a href="./mod/mod_mime.html#addoutputfilter">AddOutputFilter</a></code></li><li><code class="directive"><a href="./mod/mod_mime.html#removeinputfilter">RemoveInputFilter</a></code></li><li><code class="directive"><a href="./mod/mod_mime.html#removeoutputfilter">RemoveOutputFilter</a></code></li><li><code class="directive"><a href="./mod/mod_reflector.html#reflectorheader">ReflectorHeader</a></code></li><li><code class="directive"><a href="./mod/mod_ext_filter.html#extfilterdefine">ExtFilterDefine</a></code></li><li><code class="directive"><a href="./mod/mod_ext_filter.html#extfilteroptions">ExtFilterOptions</a></code></li><li><code class="directive"><a href="./mod/core.html#setinputfilter">SetInputFilter</a></code></li><li><code class="directive"><a href="./mod/core.html#setoutputfilter">SetOutputFilter</a></code></li></ul></td></tr></table> + +<p>The Filter Chain is available in Apache 2.0 and higher, +and enables applications to process incoming and outgoing data +in a highly flexible and configurable manner, regardless of +where the data comes from. We can pre-process incoming data, +and post-process outgoing data, at will. This is basically +independent of the traditional request processing phases.</p> +<p class="figure"> +<img src="images/filter_arch.png" width="569" height="392" alt="Filters can be chained, in a Data Axis orthogonal to request processing" /> +</p> +<p>Some examples of filtering in the standard Apache distribution are:</p> +<ul> +<li><code class="module"><a href="./mod/mod_include.html">mod_include</a></code>, implements server-side includes.</li> +<li><code class="module"><a href="./mod/mod_ssl.html">mod_ssl</a></code>, implements SSL encryption (https).</li> +<li><code class="module"><a href="./mod/mod_deflate.html">mod_deflate</a></code>, implements compression/decompression on the fly.</li> +<li><code class="module"><a href="./mod/mod_charset_lite.html">mod_charset_lite</a></code>, transcodes between different character sets.</li> +<li><code class="module"><a href="./mod/mod_ext_filter.html">mod_ext_filter</a></code>, runs an external program as a filter.</li> +</ul> +<p>Apache also uses a number of filters internally to perform +functions like chunking and byte-range handling.</p> + +<p>A wider range of applications are implemented by third-party filter +modules. A few of these are:</p> + +<ul> +<li>HTML and XML processing and rewriting</li> +<li>XSLT transforms and XIncludes</li> +<li>XML Namespace support</li> +<li>File Upload handling and decoding of HTML Forms</li> +<li>Image processing</li> +<li>Protection of vulnerable applications such as PHP scripts</li> +<li>Text search-and-replace editing</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="smart" id="smart">Smart Filtering</a></h2> + +<p class="figure"> +<img src="images/mod_filter_new.png" width="423" height="331" alt="Smart filtering applies different filter providers according to the state of request processing" /> +</p> +<p><code class="module"><a href="./mod/mod_filter.html">mod_filter</a></code>, included in Apache 2.1 and later, +enables the filter chain to be configured dynamically at run time. +So for example you can set up a proxy to rewrite +HTML with an HTML filter and JPEG images with a completely +separate filter, despite the proxy having no prior information +about what the origin server will send. This works by using a +filter harness, that dispatches to different providers according +to the actual contents at runtime. Any filter may be either +inserted directly in the chain and run unconditionally, or +used as a provider and inserted dynamically. For example,</p> +<ul> +<li>an HTML processing filter will only run if the content is +text/html or application/xhtml+xml</li> +<li>A compression filter will only run if the input is a +compressible type and not already compressed</li> +<li>A charset conversion filter will be inserted if a text +document is not already in the desired charset</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="service" id="service">Exposing Filters as an HTTP Service</a></h2> + + +<p>Filters can be used to process content originating from the client in +addition to processing content originating on the server using the +<code class="module"><a href="./mod/mod_reflector.html">mod_reflector</a></code> module.</p> + +<p><code class="module"><a href="./mod/mod_reflector.html">mod_reflector</a></code> accepts POST requests from clients, and reflects +the content request body received within the POST request back in the response, +passing through the output filter stack on the way back to the client.</p> + +<p>This technique can be used as an alternative to a web service running within +an application server stack, where an output filter provides the transformation +required on the request body. For example, the <code class="module"><a href="./mod/mod_deflate.html">mod_deflate</a></code> +module might be used to provide a general compression service, or an image +transformation filter might be turned into an image transformation service.</p> + +</div><div class="top"><a href="#page-header"><img alt="top" src="./images/up.gif" /></a></div> +<div class="section"> +<h2><a name="using" id="using">Using Filters</a></h2> + +<p>There are two ways to use filtering: Simple and Dynamic. +In general, you should use one or the other; mixing them can +have unexpected consequences (although simple Input filtering +can be mixed freely with either simple or dynamic Output filtering).</p> +<p>The Simple Way is the only way to configure input filters, and is +sufficient for output filters where you need a static filter chain. +Relevant directives are + <code class="directive"><a href="./mod/core.html#setinputfilter">SetInputFilter</a></code>, + <code class="directive"><a href="./mod/core.html#setoutputfilter">SetOutputFilter</a></code>, + <code class="directive"><a href="./mod/mod_mime.html#addinputfilter">AddInputFilter</a></code>, + <code class="directive"><a href="./mod/mod_mime.html#addoutputfilter">AddOutputFilter</a></code>, + <code class="directive"><a href="./mod/mod_mime.html#removeinputfilter">RemoveInputFilter</a></code>, and + <code class="directive"><a href="./mod/mod_mime.html#removeoutputfilter">RemoveOutputFilter</a></code>.</p> + +<p>The Dynamic Way enables both static and flexible, dynamic configuration +of output filters, as discussed in the <code class="module"><a href="./mod/mod_filter.html">mod_filter</a></code> page. +Relevant directives are + <code class="directive"><a href="./mod/mod_filter.html#filterchain">FilterChain</a></code>, + <code class="directive"><a href="./mod/mod_filter.html#filterdeclare">FilterDeclare</a></code>, and + <code class="directive"><a href="./mod/mod_filter.html#filterprovider">FilterProvider</a></code>.</p> + +<p>One further directive <code class="directive"><a href="./mod/mod_filter.html#addoutputfilterbytype">AddOutputFilterByType</a></code> is still supported, +but deprecated. Use dynamic configuration instead.</p> + + </div></div> +<div class="bottomlang"> +<p><span>Available Languages: </span><a href="./en/filter.html" title="English"> en </a> | +<a href="./es/filter.html" hreflang="es" rel="alternate" title="Español"> es </a> | +<a href="./fr/filter.html" hreflang="fr" rel="alternate" title="Français"> fr </a> | +<a href="./ja/filter.html" hreflang="ja" rel="alternate" title="Japanese"> ja </a> | +<a href="./ko/filter.html" hreflang="ko" rel="alternate" title="Korean"> ko </a> | +<a href="./tr/filter.html" hreflang="tr" rel="alternate" title="Türkçe"> tr </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. Comments placed here should be pointed towards suggestions on improving the documentation or server, and may be removed by our moderators if they are either implemented or considered invalid/off-topic. Questions on how to manage the Apache HTTP Server should be directed at either our IRC channel, #httpd, on Libera.chat, or sent to our <a href="https://httpd.apache.org/lists.html">mailing lists</a>.</div> +<script type="text/javascript"><!--//--><![CDATA[//><!-- +var comments_shortname = 'httpd'; +var comments_identifier = 'http://httpd.apache.org/docs/2.4/filter.html'; +(function(w, d) { + if (w.location.hostname.toLowerCase() == "httpd.apache.org") { + d.write('<div id="comments_thread"><\/div>'); + var s = d.createElement('script'); + s.type = 'text/javascript'; + s.async = true; + s.src = 'https://comments.apache.org/show_comments.lua?site=' + comments_shortname + '&page=' + comments_identifier; + (d.getElementsByTagName('head')[0] || d.getElementsByTagName('body')[0]).appendChild(s); + } + else { + d.write('<div id="comments_thread">Comments are disabled for this page at the moment.<\/div>'); + } +})(window, document); +//--><!]]></script></div><div id="footer"> +<p class="apache">Copyright 2023 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="http://wiki.apache.org/httpd/FAQ">FAQ</a> | <a href="./glossary.html">Glossary</a> | <a href="./sitemap.html">Sitemap</a></p></div><script type="text/javascript"><!--//--><![CDATA[//><!-- +if (typeof(prettyPrint) !== 'undefined') { + prettyPrint(); +} +//--><!]]></script> +</body></html>
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