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784 lines
23 KiB
XML
784 lines
23 KiB
XML
<?xml version="1.0" encoding="UTF-8" ?>
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<!DOCTYPE manualpage SYSTEM "../style/manualpage.dtd">
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<?xml-stylesheet type="text/xsl" href="../style/manual.en.xsl"?>
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<!-- $LastChangedRevision$ -->
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<!--
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Copyright 2002-2005 The Apache Software Foundation or its licensors, as
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applicable.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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-->
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<manualpage metafile="rewrite_guide.xml.meta">
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<parentdocument href="./index.html" />
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<title>URL Rewriting Guide</title>
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<summary>
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<p>This document supplements the <module>mod_rewrite</module>
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<a href="../mod/mod_rewrite.html">reference documentation</a>.
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It describes how one can use Apache's <module>mod_rewrite</module>
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to solve typical URL-based problems with which webmasters are
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commonony confronted. We give detailed descriptions on how to
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solve each problem by configuring URL rewriting rulesets.</p>
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<note type="warning">ATTENTION: Depending on your server configuration
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it may be necessary to slightly change the examples for your
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situation, e.g. adding the <code>[PT]</code> flag when
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additionally using <module>mod_alias</module> and
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<module>mod_userdir</module>, etc. Or rewriting a ruleset
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to fit in <code>.htaccess</code> context instead
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of per-server context. Always try to understand what a
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particular ruleset really does before you use it. This
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avoids many problems.</note>
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</summary>
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<seealso><a href="../mod/mod_rewrite.html">Module
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documentation</a></seealso>
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<seealso><a href="rewrite_intro.html">mod_rewrite
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introduction</a></seealso>
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<seealso><a href="rewrite_guide_advanced.html">Practical solutions to
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advanced problems</a></seealso>
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<seealso><a href="rewrite_tech.html">Technical details</a></seealso>
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<section id="canonicalurl">
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<title>Canonical URLs</title>
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<dl>
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<dt>Description:</dt>
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<dd>
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<p>On some webservers there are more than one URL for a
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resource. Usually there are canonical URLs (which should be
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actually used and distributed) and those which are just
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shortcuts, internal ones, etc. Independent of which URL the
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user supplied with the request he should finally see the
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canonical one only.</p>
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</dd>
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<dt>Solution:</dt>
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<dd>
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<p>We do an external HTTP redirect for all non-canonical
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URLs to fix them in the location view of the Browser and
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for all subsequent requests. In the example ruleset below
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we replace <code>/~user</code> by the canonical
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<code>/u/user</code> and fix a missing trailing slash for
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<code>/u/user</code>.</p>
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<example><pre>
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RewriteRule ^/<strong>~</strong>([^/]+)/?(.*) /<strong>u</strong>/$1/$2 [<strong>R</strong>]
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RewriteRule ^/([uge])/(<strong>[^/]+</strong>)$ /$1/$2<strong>/</strong> [<strong>R</strong>]
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</pre></example>
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</dd>
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</dl>
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</section>
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<section id="canonicalhost"><title>Canonical Hostnames</title>
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<dl>
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<dt>Description:</dt>
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<dd>The goal of this rule is to force the use of a particular
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hostname, in preference to other hostnames which may be used to
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reach the same site. For example, if you wish to force the use
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of <strong>www.example.com</strong> instead of
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<strong>example.com</strong>, you might use a variant of the
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following recipe.</dd>
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<dt>Solution:</dt>
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<dd>
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<p>For sites running on a port other than 80:</p>
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<example><pre>
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RewriteCond %{HTTP_HOST} !^fully\.qualified\.domain\.name [NC]
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RewriteCond %{HTTP_HOST} !^$
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RewriteCond %{SERVER_PORT} !^80$
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RewriteRule ^/(.*) http://fully.qualified.domain.name:%{SERVER_PORT}/$1 [L,R]
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</pre></example>
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<p>And for a site running on port 80</p>
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<example><pre>
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RewriteCond %{HTTP_HOST} !^fully\.qualified\.domain\.name [NC]
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RewriteCond %{HTTP_HOST} !^$
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RewriteRule ^/(.*) http://fully.qualified.domain.name/$1 [L,R]
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</pre></example>
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</dd>
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</dl>
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</section>
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<section id="moveddocroot">
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<title>Moved <code>DocumentRoot</code></title>
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<dl>
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<dt>Description:</dt>
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<dd>
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<p>Usually the <directive module="core">DocumentRoot</directive>
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of the webserver directly relates to the URL "<code>/</code>".
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But often this data is not really of top-level priority. For example,
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you may wish for visitors, on first entering a site, to go to a
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particular subdirectory <code>/about/</code>. This may be accomplished
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using the following ruleset:</p>
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</dd>
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<dt>Solution:</dt>
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<dd>
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<p>We redirect the URL <code>/</code> to
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<code>/about/</code>:
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</p>
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<example><pre>
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RewriteEngine on
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RewriteRule <strong>^/$</strong> /about/ [<strong>R</strong>]
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</pre></example>
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<p>Note that this can also be handled using the <directive
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module="mod_alias">RedirectMatch</directive> directive:</p>
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<example>
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RedirectMatch ^/$ http://example.com/e/www/
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</example>
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</dd>
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</dl>
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</section>
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<section id="trailingslash">
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<title>Trailing Slash Problem</title>
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<dl>
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<dt>Description:</dt>
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<dd><p>The vast majority of "trailing slash" problems can be dealt
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with using the techniques discussed in the <a
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href="http://httpd.apache.org/docs/misc/FAQ-E.html#set-servername">FAQ
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entry</a>. However, occasionally, there is a need to use mod_rewrite
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to handle a case where a missing trailing slash causes a URL to
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fail. This can happen, for example, after a series of complex
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rewrite rules.</p>
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</dd>
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<dt>Solution:</dt>
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<dd>
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<p>The solution to this subtle problem is to let the server
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add the trailing slash automatically. To do this
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correctly we have to use an external redirect, so the
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browser correctly requests subsequent images etc. If we
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only did a internal rewrite, this would only work for the
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directory page, but would go wrong when any images are
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included into this page with relative URLs, because the
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browser would request an in-lined object. For instance, a
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request for <code>image.gif</code> in
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<code>/~quux/foo/index.html</code> would become
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<code>/~quux/image.gif</code> without the external
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redirect!</p>
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<p>So, to do this trick we write:</p>
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<example><pre>
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RewriteEngine on
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RewriteBase /~quux/
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RewriteRule ^foo<strong>$</strong> foo<strong>/</strong> [<strong>R</strong>]
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</pre></example>
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<p>Alternately, you can put the following in a
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top-level <code>.htaccess</code> file in the content directory.
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But note that this creates some processing overhead.</p>
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<example><pre>
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RewriteEngine on
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RewriteBase /~quux/
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RewriteCond %{REQUEST_FILENAME} <strong>-d</strong>
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RewriteRule ^(.+<strong>[^/]</strong>)$ $1<strong>/</strong> [R]
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</pre></example>
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</dd>
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</dl>
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</section>
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<section id="movehomedirs">
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<title>Move Homedirs to Different Webserver</title>
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<dl>
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<dt>Description:</dt>
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<dd>
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<p>Many webmasters have asked for a solution to the
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following situation: They wanted to redirect just all
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homedirs on a webserver to another webserver. They usually
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need such things when establishing a newer webserver which
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will replace the old one over time.</p>
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</dd>
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<dt>Solution:</dt>
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<dd>
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<p>The solution is trivial with <module>mod_rewrite</module>.
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On the old webserver we just redirect all
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<code>/~user/anypath</code> URLs to
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<code>http://newserver/~user/anypath</code>.</p>
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<example><pre>
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RewriteEngine on
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RewriteRule ^/~(.+) http://<strong>newserver</strong>/~$1 [R,L]
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</pre></example>
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</dd>
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</dl>
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</section>
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<section id="multipledirs">
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<title>Search pages in more than one directory</title>
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<dl>
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<dt>Description:</dt>
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<dd>
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<p>Sometimes it is necessary to let the webserver search
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for pages in more than one directory. Here MultiViews or
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other techniques cannot help.</p>
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</dd>
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<dt>Solution:</dt>
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<dd>
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<p>We program a explicit ruleset which searches for the
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files in the directories.</p>
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<example><pre>
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RewriteEngine on
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# first try to find it in custom/...
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# ...and if found stop and be happy:
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RewriteCond /your/docroot/<strong>dir1</strong>/%{REQUEST_FILENAME} -f
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RewriteRule ^(.+) /your/docroot/<strong>dir1</strong>/$1 [L]
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# second try to find it in pub/...
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# ...and if found stop and be happy:
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RewriteCond /your/docroot/<strong>dir2</strong>/%{REQUEST_FILENAME} -f
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RewriteRule ^(.+) /your/docroot/<strong>dir2</strong>/$1 [L]
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# else go on for other Alias or ScriptAlias directives,
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# etc.
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RewriteRule ^(.+) - [PT]
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</pre></example>
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</dd>
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</dl>
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</section>
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<section id="setenvvars">
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<title>Set Environment Variables According To URL Parts</title>
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<dl>
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<dt>Description:</dt>
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<dd>
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<p>Perhaps you want to keep status information between
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requests and use the URL to encode it. But you don't want
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to use a CGI wrapper for all pages just to strip out this
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information.</p>
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</dd>
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<dt>Solution:</dt>
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<dd>
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<p>We use a rewrite rule to strip out the status information
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and remember it via an environment variable which can be
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later dereferenced from within XSSI or CGI. This way a
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URL <code>/foo/S=java/bar/</code> gets translated to
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<code>/foo/bar/</code> and the environment variable named
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<code>STATUS</code> is set to the value "java".</p>
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<example><pre>
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RewriteEngine on
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RewriteRule ^(.*)/<strong>S=([^/]+)</strong>/(.*) $1/$3 [E=<strong>STATUS:$2</strong>]
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</pre></example>
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</dd>
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</dl>
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</section>
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<section id="uservhosts">
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<title>Virtual User Hosts</title>
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<dl>
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<dt>Description:</dt>
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<dd>
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<p>Assume that you want to provide
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<code>www.<strong>username</strong>.host.domain.com</code>
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for the homepage of username via just DNS A records to the
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same machine and without any virtualhosts on this
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machine.</p>
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</dd>
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<dt>Solution:</dt>
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<dd>
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<p>For HTTP/1.0 requests there is no solution, but for
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HTTP/1.1 requests which contain a Host: HTTP header we
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can use the following ruleset to rewrite
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<code>http://www.username.host.com/anypath</code>
|
|
internally to <code>/home/username/anypath</code>:</p>
|
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|
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<example><pre>
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RewriteEngine on
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RewriteCond %{<strong>HTTP_HOST</strong>} ^www\.<strong>[^.]+</strong>\.host\.com$
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RewriteRule ^(.+) %{HTTP_HOST}$1 [C]
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RewriteRule ^www\.<strong>([^.]+)</strong>\.host\.com(.*) /home/<strong>$1</strong>$2
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</pre></example>
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</dd>
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</dl>
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</section>
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<section id="redirecthome">
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<title>Redirect Homedirs For Foreigners</title>
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<dl>
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<dt>Description:</dt>
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<dd>
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<p>We want to redirect homedir URLs to another webserver
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<code>www.somewhere.com</code> when the requesting user
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|
does not stay in the local domain
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<code>ourdomain.com</code>. This is sometimes used in
|
|
virtual host contexts.</p>
|
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</dd>
|
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<dt>Solution:</dt>
|
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<dd>
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<p>Just a rewrite condition:</p>
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<example><pre>
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RewriteEngine on
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RewriteCond %{REMOTE_HOST} <strong>!^.+\.ourdomain\.com$</strong>
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RewriteRule ^(/~.+) http://www.somewhere.com/$1 [R,L]
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</pre></example>
|
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</dd>
|
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</dl>
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|
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</section>
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|
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<section id="redirectanchors">
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<title>Redirecting Anchors</title>
|
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|
|
<dl>
|
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<dt>Description:</dt>
|
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<dd>
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<p>By default, redirecting to an HTML anchor doesn't work,
|
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because mod_rewrite escapes the <code>#</code> character,
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turning it into <code>%23</code>. This, in turn, breaks the
|
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redirection.</p>
|
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</dd>
|
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|
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<dt>Solution:</dt>
|
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|
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<dd>
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<p>Use the <code>[NE]</code> flag on the
|
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<code>RewriteRule</code>. NE stands for No Escape.
|
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</p>
|
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</dd>
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</dl>
|
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|
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</section>
|
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|
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<section>
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<title>Time-Dependent Rewriting</title>
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<dl>
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<dt>Description:</dt>
|
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|
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<dd>
|
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<p>When tricks like time-dependent content should happen a
|
|
lot of webmasters still use CGI scripts which do for
|
|
instance redirects to specialized pages. How can it be done
|
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via <module>mod_rewrite</module>?</p>
|
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</dd>
|
|
|
|
<dt>Solution:</dt>
|
|
|
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<dd>
|
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<p>There are a lot of variables named <code>TIME_xxx</code>
|
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for rewrite conditions. In conjunction with the special
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lexicographic comparison patterns <code><STRING</code>,
|
|
<code>>STRING</code> and <code>=STRING</code> we can
|
|
do time-dependent redirects:</p>
|
|
|
|
<example><pre>
|
|
RewriteEngine on
|
|
RewriteCond %{TIME_HOUR}%{TIME_MIN} >0700
|
|
RewriteCond %{TIME_HOUR}%{TIME_MIN} <1900
|
|
RewriteRule ^foo\.html$ foo.day.html
|
|
RewriteRule ^foo\.html$ foo.night.html
|
|
</pre></example>
|
|
|
|
<p>This provides the content of <code>foo.day.html</code>
|
|
under the URL <code>foo.html</code> from
|
|
<code>07:00-19:00</code> and at the remaining time the
|
|
contents of <code>foo.night.html</code>. Just a nice
|
|
feature for a homepage...</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</section>
|
|
|
|
<section>
|
|
|
|
<title>Backward Compatibility for YYYY to XXXX migration</title>
|
|
|
|
<dl>
|
|
<dt>Description:</dt>
|
|
|
|
<dd>
|
|
<p>How can we make URLs backward compatible (still
|
|
existing virtually) after migrating <code>document.YYYY</code>
|
|
to <code>document.XXXX</code>, e.g. after translating a
|
|
bunch of <code>.html</code> files to <code>.phtml</code>?</p>
|
|
</dd>
|
|
|
|
<dt>Solution:</dt>
|
|
|
|
<dd>
|
|
<p>We just rewrite the name to its basename and test for
|
|
existence of the new extension. If it exists, we take
|
|
that name, else we rewrite the URL to its original state.</p>
|
|
|
|
|
|
<example><pre>
|
|
# backward compatibility ruleset for
|
|
# rewriting document.html to document.phtml
|
|
# when and only when document.phtml exists
|
|
# but no longer document.html
|
|
RewriteEngine on
|
|
RewriteBase /~quux/
|
|
# parse out basename, but remember the fact
|
|
RewriteRule ^(.*)\.html$ $1 [C,E=WasHTML:yes]
|
|
# rewrite to document.phtml if exists
|
|
RewriteCond %{REQUEST_FILENAME}.phtml -f
|
|
RewriteRule ^(.*)$ $1.phtml [S=1]
|
|
# else reverse the previous basename cutout
|
|
RewriteCond %{ENV:WasHTML} ^yes$
|
|
RewriteRule ^(.*)$ $1.html
|
|
</pre></example>
|
|
</dd>
|
|
</dl>
|
|
|
|
</section>
|
|
|
|
<section id="content">
|
|
|
|
<title>Content Handling</title>
|
|
|
|
<section>
|
|
|
|
<title>From Old to New (intern)</title>
|
|
|
|
<dl>
|
|
<dt>Description:</dt>
|
|
|
|
<dd>
|
|
<p>Assume we have recently renamed the page
|
|
<code>foo.html</code> to <code>bar.html</code> and now want
|
|
to provide the old URL for backward compatibility. Actually
|
|
we want that users of the old URL even not recognize that
|
|
the pages was renamed.</p>
|
|
</dd>
|
|
|
|
<dt>Solution:</dt>
|
|
|
|
<dd>
|
|
<p>We rewrite the old URL to the new one internally via the
|
|
following rule:</p>
|
|
|
|
<example><pre>
|
|
RewriteEngine on
|
|
RewriteBase /~quux/
|
|
RewriteRule ^<strong>foo</strong>\.html$ <strong>bar</strong>.html
|
|
</pre></example>
|
|
</dd>
|
|
</dl>
|
|
|
|
</section>
|
|
|
|
<section>
|
|
|
|
<title>From Old to New (extern)</title>
|
|
|
|
<dl>
|
|
<dt>Description:</dt>
|
|
|
|
<dd>
|
|
<p>Assume again that we have recently renamed the page
|
|
<code>foo.html</code> to <code>bar.html</code> and now want
|
|
to provide the old URL for backward compatibility. But this
|
|
time we want that the users of the old URL get hinted to
|
|
the new one, i.e. their browsers Location field should
|
|
change, too.</p>
|
|
</dd>
|
|
|
|
<dt>Solution:</dt>
|
|
|
|
<dd>
|
|
<p>We force a HTTP redirect to the new URL which leads to a
|
|
change of the browsers and thus the users view:</p>
|
|
|
|
<example><pre>
|
|
RewriteEngine on
|
|
RewriteBase /~quux/
|
|
RewriteRule ^<strong>foo</strong>\.html$ <strong>bar</strong>.html [<strong>R</strong>]
|
|
</pre></example>
|
|
</dd>
|
|
</dl>
|
|
|
|
</section>
|
|
|
|
<section>
|
|
|
|
<title>From Static to Dynamic</title>
|
|
|
|
<dl>
|
|
<dt>Description:</dt>
|
|
|
|
<dd>
|
|
<p>How can we transform a static page
|
|
<code>foo.html</code> into a dynamic variant
|
|
<code>foo.cgi</code> in a seamless way, i.e. without notice
|
|
by the browser/user.</p>
|
|
</dd>
|
|
|
|
<dt>Solution:</dt>
|
|
|
|
<dd>
|
|
<p>We just rewrite the URL to the CGI-script and force the
|
|
correct MIME-type so it gets really run as a CGI-script.
|
|
This way a request to <code>/~quux/foo.html</code>
|
|
internally leads to the invocation of
|
|
<code>/~quux/foo.cgi</code>.</p>
|
|
|
|
<example><pre>
|
|
RewriteEngine on
|
|
RewriteBase /~quux/
|
|
RewriteRule ^foo\.<strong>html</strong>$ foo.<strong>cgi</strong> [T=<strong>application/x-httpd-cgi</strong>]
|
|
</pre></example>
|
|
</dd>
|
|
</dl>
|
|
|
|
</section>
|
|
</section>
|
|
|
|
<section id="access">
|
|
|
|
<title>Access Restriction</title>
|
|
|
|
<section>
|
|
|
|
<title>Blocking of Robots</title>
|
|
|
|
<dl>
|
|
<dt>Description:</dt>
|
|
|
|
<dd>
|
|
<p>How can we block a really annoying robot from
|
|
retrieving pages of a specific webarea? A
|
|
<code>/robots.txt</code> file containing entries of the
|
|
"Robot Exclusion Protocol" is typically not enough to get
|
|
rid of such a robot.</p>
|
|
</dd>
|
|
|
|
<dt>Solution:</dt>
|
|
|
|
<dd>
|
|
<p>We use a ruleset which forbids the URLs of the webarea
|
|
<code>/~quux/foo/arc/</code> (perhaps a very deep
|
|
directory indexed area where the robot traversal would
|
|
create big server load). We have to make sure that we
|
|
forbid access only to the particular robot, i.e. just
|
|
forbidding the host where the robot runs is not enough.
|
|
This would block users from this host, too. We accomplish
|
|
this by also matching the User-Agent HTTP header
|
|
information.</p>
|
|
|
|
<example><pre>
|
|
RewriteCond %{HTTP_USER_AGENT} ^<strong>NameOfBadRobot</strong>.*
|
|
RewriteCond %{REMOTE_ADDR} ^<strong>123\.45\.67\.[8-9]</strong>$
|
|
RewriteRule ^<strong>/~quux/foo/arc/</strong>.+ - [<strong>F</strong>]
|
|
</pre></example>
|
|
</dd>
|
|
</dl>
|
|
|
|
</section>
|
|
|
|
<section>
|
|
|
|
<title>Blocked Inline-Images</title>
|
|
|
|
<dl>
|
|
<dt>Description:</dt>
|
|
|
|
<dd>
|
|
<p>Assume we have under <code>http://www.quux-corp.de/~quux/</code>
|
|
some pages with inlined GIF graphics. These graphics are
|
|
nice, so others directly incorporate them via hyperlinks to
|
|
their pages. We don't like this practice because it adds
|
|
useless traffic to our server.</p>
|
|
</dd>
|
|
|
|
<dt>Solution:</dt>
|
|
|
|
<dd>
|
|
<p>While we cannot 100% protect the images from inclusion,
|
|
we can at least restrict the cases where the browser
|
|
sends a HTTP Referer header.</p>
|
|
|
|
<example><pre>
|
|
RewriteCond %{HTTP_REFERER} <strong>!^$</strong>
|
|
RewriteCond %{HTTP_REFERER} !^http://www.quux-corp.de/~quux/.*$ [NC]
|
|
RewriteRule <strong>.*\.gif$</strong> - [F]
|
|
</pre></example>
|
|
|
|
<example><pre>
|
|
RewriteCond %{HTTP_REFERER} !^$
|
|
RewriteCond %{HTTP_REFERER} !.*/foo-with-gif\.html$
|
|
RewriteRule <strong>^inlined-in-foo\.gif$</strong> - [F]
|
|
</pre></example>
|
|
</dd>
|
|
</dl>
|
|
|
|
</section>
|
|
|
|
<section>
|
|
|
|
<title>Proxy Deny</title>
|
|
|
|
<dl>
|
|
<dt>Description:</dt>
|
|
|
|
<dd>
|
|
<p>How can we forbid a certain host or even a user of a
|
|
special host from using the Apache proxy?</p>
|
|
</dd>
|
|
|
|
<dt>Solution:</dt>
|
|
|
|
<dd>
|
|
<p>We first have to make sure <module>mod_rewrite</module>
|
|
is below(!) <module>mod_proxy</module> in the Configuration
|
|
file when compiling the Apache webserver. This way it gets
|
|
called <em>before</em> <module>mod_proxy</module>. Then we
|
|
configure the following for a host-dependent deny...</p>
|
|
|
|
<example><pre>
|
|
RewriteCond %{REMOTE_HOST} <strong>^badhost\.mydomain\.com$</strong>
|
|
RewriteRule !^http://[^/.]\.mydomain.com.* - [F]
|
|
</pre></example>
|
|
|
|
<p>...and this one for a user@host-dependent deny:</p>
|
|
|
|
<example><pre>
|
|
RewriteCond %{REMOTE_IDENT}@%{REMOTE_HOST} <strong>^badguy@badhost\.mydomain\.com$</strong>
|
|
RewriteRule !^http://[^/.]\.mydomain.com.* - [F]
|
|
</pre></example>
|
|
</dd>
|
|
</dl>
|
|
|
|
</section>
|
|
|
|
</section>
|
|
|
|
<section id="other">
|
|
|
|
<title>Other</title>
|
|
|
|
<section>
|
|
|
|
<title>External Rewriting Engine</title>
|
|
|
|
<dl>
|
|
<dt>Description:</dt>
|
|
|
|
<dd>
|
|
<p>A FAQ: How can we solve the FOO/BAR/QUUX/etc.
|
|
problem? There seems no solution by the use of
|
|
<module>mod_rewrite</module>...</p>
|
|
</dd>
|
|
|
|
<dt>Solution:</dt>
|
|
|
|
<dd>
|
|
<p>Use an external <directive module="mod_rewrite"
|
|
>RewriteMap</directive>, i.e. a program which acts
|
|
like a <directive module="mod_rewrite"
|
|
>RewriteMap</directive>. It is run once on startup of Apache
|
|
receives the requested URLs on <code>STDIN</code> and has
|
|
to put the resulting (usually rewritten) URL on
|
|
<code>STDOUT</code> (same order!).</p>
|
|
|
|
<example><pre>
|
|
RewriteEngine on
|
|
RewriteMap quux-map <strong>prg:</strong>/path/to/map.quux.pl
|
|
RewriteRule ^/~quux/(.*)$ /~quux/<strong>${quux-map:$1}</strong>
|
|
</pre></example>
|
|
|
|
<example><pre>
|
|
#!/path/to/perl
|
|
|
|
# disable buffered I/O which would lead
|
|
# to deadloops for the Apache server
|
|
$| = 1;
|
|
|
|
# read URLs one per line from stdin and
|
|
# generate substitution URL on stdout
|
|
while (<>) {
|
|
s|^foo/|bar/|;
|
|
print $_;
|
|
}
|
|
</pre></example>
|
|
|
|
<p>This is a demonstration-only example and just rewrites
|
|
all URLs <code>/~quux/foo/...</code> to
|
|
<code>/~quux/bar/...</code>. Actually you can program
|
|
whatever you like. But notice that while such maps can be
|
|
<strong>used</strong> also by an average user, only the
|
|
system administrator can <strong>define</strong> it.</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
</section>
|
|
|
|
</section>
|
|
|
|
</manualpage>
|
|
|