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diff --git a/docs/manual/rewrite/rewrite_flags.html.en b/docs/manual/rewrite/rewrite_flags.html.en new file mode 100644 index 00000000..7063cc57 --- /dev/null +++ b/docs/manual/rewrite/rewrite_flags.html.en @@ -0,0 +1,420 @@ +<?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>Apache mod_rewrite Flags - 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 id="manual-page"><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 2.2</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 2.2</a> > <a href="./">Rewrite</a></div><div id="page-content"><div id="preamble"><h1>Apache mod_rewrite Flags</h1> +<div class="toplang"> +<p><span>Available Languages: </span><a href="../en/rewrite/rewrite_flags.html" title="English"> en </a></p> +</div> + +<p>This document discusses the flags which are available to the +<code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directive, +providing detailed explanations and examples. This is not necessarily +a comprehensive list of all flags available, so be sure to also +consult the reference documentation.</p> +</div> +<div id="quickview"><ul id="toc"><li><img alt="" src="../images/down.gif" /> <a href="#introduction">Introduction</a></li> +<li><img alt="" src="../images/down.gif" /> <a href="#flags">The flags</a></li> +</ul><h3>See also</h3><ul class="seealso"><li><a href="../mod/mod_rewrite.html">Module documentation</a></li><li><a href="rewrite_tech.html">Technical details</a></li><li><a href="rewrite_guide.html">Rewrite Guide - useful examples</a></li><li><a href="rewrite_guide_advanced.html">Advanced Rewrite Guide - +advanced useful examples</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="introduction" id="introduction">Introduction</a></h2> +<p><code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code>s can have +their behavior modified by one or more flags. Flags are included in +square brackets at the end of the rule, and multiple flags are separated +by commas.</p> +<div class="example"><p><code> +RewriteRule pattern target [Flag1,Flag2,Flag3] +</code></p></div> + +<p>The flags all have a short form, such as <code>CO</code>, as well as +a longer form, such as <code>cookie</code>. Some flags take one or more +arguments. Flags are not case sensitive.</p> + +</div><div class="top"><a href="#page-header"><img alt="top" src="../images/up.gif" /></a></div> +<div class="section"> +<h2><a name="flags" id="flags">The flags</a></h2> + +<p>Each flag has a long and short form. While it is most common to use +the short form, it is recommended that you familiarize yourself with the +long form, so that you remember what each flag is supposed to do.</p> + +<p>Presented here are each of the available flags, along with an example +of how you might use them.</p> + +<h3><a name="flag_c" id="flag_c">C|chain</a></h3> +<p>The [C] or [chain] flag indicates that the <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> is chained to the next +rule. That is, if the rule matches, then it is processed as usual and +control moves on to the next rule. However, if it does not match, then +the next rule, and any other rules that are chained together, will be +skipped.</p> + + + +<h3><a name="flag_co" id="flag_co">CO|cookie</a></h3> +<p>The [CO], or [cookie] flag, allows you to set a cookie when a +particular <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> +matches. The argument consists of three required fields and two optional +fields.</p> +<p>You must declare a name and value for the cookie to be set, and the +domain for which you wish the cookie to be valid. You may optionally set +the lifetime of the cookie, and the path for which it should be +returned.</p> +<p>By default, the lifetime of the cookie is the current browser +session.</p> +<p>By default, the path for which the cookie will be valid is "/" - that +is, the entire website.</p> +<p>Several examples are offered here:</p> + +<div class="example"><p><code> +RewriteEngine On<br /> +RewriteRule ^/index.html - [CO=frontdoor:yes:.apache.org:1440:/] +</code></p></div> + +<p>This rule doesn't rewrite the request (the "-" rewrite target tells +mod_rewrite to pass the request through unchanged) but sets a cookie +called 'frontdoor' to a value of 'yes'. The cookie is valid for any host +in the <code>.apache.org</code> domain. It will be set to expire in 1440 +minutes (24 hours) and will be returned for all URIs.</p> + + + +<h3><a name="flag_e" id="flag_e">E|env</a></h3> +<p>With the [E], or [env] flag, you can set the value of an environment +variable. Note that some environment variables may be set after the rule +is run, thus unsetting what you have set. See <a href="../env.html">the +Environment Variables document</a> for more details on how Environment +variables work.</p> + +<p>The following example sets an evironment variable called 'image' to a +value of '1' if the requested URI is an image file. Then, that +environment variable is used to exclude those requests from the access +log.</p> + +<div class="example"><p><code> +RewriteRule \.(png|gif|jpg) - [E=image:1]<br /> +CustomLog logs/access_log combined env=!image +</code></p></div> + +<p>Note that this same effect can be obtained using <code class="directive"><a href="../mod/mod_setenvif.html#setenvif">SetEnvIf</a></code>. This technique is offered as +an example, not as a recommendation.</p> + + +<h3><a name="flag_f" id="flag_f">F|forbidden</a></h3> +<p>Using the [F] flag causes Apache to return a 403 Forbidden status +code to the client. While the same behavior can be accomplished using +the <code class="directive"><a href="../mod/mod_access.html#deny">Deny</a></code> directive, this +allows more flexibility in assigning a Forbidden status.</p> + +<p>The following rule will forbid <code>.exe</code> files from being +downloaded from your server.</p> + +<div class="example"><p><code> +RewriteRule \.exe - [F] +</code></p></div> + +<p>This example uses the "-" syntax for the rewrite target, which means +that the requested URI is not modified. There's no reason to rewrite to +another URI, if you're going to forbid the request.</p> + + + +<h3><a name="flag_g" id="flag_g">G|gone</a></h3> +<p>The [G] flag forces Apache to return a 410 Gone status with the +response. This indicates that a resource used to be available, but is no +longer available.</p> + +<p>As with the [F] flag, you will typically use the "-" syntax for the +rewrite target when using the [G] flag:</p> + +<div class="example"><p><code> +RewriteRule oldproduct - [G,NC] +</code></p></div> + + +<h3><a name="flag_h" id="flag_h">H|handler</a></h3> +<p>Forces the resulting request to be handled with the specified +handler. For example, one might use this to force all files without a +file extension to be parsed by the php handler:</p> + +<div class="example"><p><code> +RewriteRule !\. - [H=application/x-httpd-php] +</code></p></div> + +<p> +The regular expression above - <code>!\.</code> - will match any request +that does not contain the literal <code>.</code> character. +</p> + + +<h3><a name="flag_l" id="flag_l">L|last</a></h3> +<p>The [L] flag causes <code class="module"><a href="../mod/mod_rewrite.html">mod_rewrite</a></code> to stop processing +the rule set. In most contexts, this means that if the rule matches, no +further rules will be processed.</p> + +<p>If you are using <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> in either +<code>.htaccess</code> files or in +<code class="directive"><a href="../mod/core.html#directory"><Directory></a></code> sections, +it is important to have some understanding of how the rules are +processed. The simplified form of this is that once the rules have been +processed, the rewritten request is handed back to the URL parsing +engine to do what it may with it. It is possible that as the rewritten +request is handled, the <code>.htaccess</code> file or +<code class="directive"><a href="../mod/core.html#directory"><Directory></a></code> section +may be encountered again, and thus the ruleset may be run again from the +start. Most commonly this will happen if one of the rules causes a +redirect - either internal or external - causing the request process to +start over.</p> + +<p>It is therefore important, if you are using <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> directives in one of these +context that you take explicit steps to avoid rules looping, and not +count solely on the [L] flag to terminate execution of a series of +rules, as shown below.</p> + +<p>The example given here will rewrite any request to +<code>index.php</code>, giving the original request as a query string +argument to <code>index.php</code>, however, if the request is already +for <code>index.php</code>, this rule will be skipped.</p> + +<div class="example"><p><code> +RewriteCond %{REQUEST_URI} !index\.php<br /> +RewriteRule ^(.*) index.php?req=$1 [L] +</code></p></div> + + +<h3><a name="flag_n" id="flag_n">N|next</a></h3> +<p> +The [N] flag causes the ruleset to start over again from the top. Use +with extreme caution, as it may result in loop. +</p> +<p> +The [Next] flag could be used, for example, if you wished to replace a +certain string or letter repeatedly in a request. The example shown here +will replace A with B everywhere in a request, and will continue doing +so until there are no more As to be replaced. +</p> + +<div class="example"><p><code> +RewriteRule (.*)A(.*) $1B$2 [N] +</code></p></div> + +<p>You can think of this as a <code>while</code> loop: While this +pattern still matches, perform this substitution.</p> + + + +<h3><a name="flag_nc" id="flag_nc">NC|nocase</a></h3> +<p>Use of the [NC] flag causes the <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> to be matched in a +case-insensitive manner. That is, it doesn't care whether letters appear +as upper-case or lower-case in the matched URI.</p> + +<p>In the example below, any request for an image file will be proxied +to your dedicated image server. The match is case-insensitive, so that +<code>.jpg</code> and <code>.JPG</code> files are both acceptable, for +example.</p> + +<div class="example"><p><code> +RewriteRule (.*\.(jpg|gif|png))$ http://images.example.com$1 [P,NC] +</code></p></div> + + +<h3><a name="flag_ne" id="flag_ne">NE|noescape</a></h3> +<p>By default, special characters, such as <code>&</code> and +<code>?</code>, for example, will be converted to their hexcode +equivalent. Using the [NE] flag prevents that from happening. +</p> + +<div class="example"><p><code> +RewriteRule ^/anchor/(.+) /bigpage.html#$1 [NE,R] +</code></p></div> + +<p> +The above example will redirect <code>/anchor/xyz</code> to +<code>/bigpage.html#xyz</code>. Omitting the [NE] will result in the # +being converted to its hexcode equivalent, <code>%23</code>, which will +then result in a 404 Not Found error condition. +</p> + + + +<h3><a name="flag_ns" id="flag_ns">NS|nosubreq</a></h3> +<p>Use of the [NS] flag prevents the rule from being used on +subrequests. For example, a page which is included using an SSI (Server +Side Include) is a subrequest, and you may want to avoid rewrites +happening on those subrequests.</p> + +<p> +Images, javascript files, or css files, loaded as part of an HTML page, +are not subrequests - the browser requests them as separate HTTP +requests. +</p> + + +<h3><a name="flag_p" id="flag_p">P|proxy</a></h3> +<p>Use of the [P] flag causes the request to be handled by +<code class="module"><a href="../mod/mod_proxy.html">mod_proxy</a></code>, and handled via a proxy request. For +example, if you wanted all image requests to be handled by a back-end +image server, you might do something like the following:</p> + +<div class="example"><p><code> +RewriteRule (.*)\.(jpg|gif|png) http://images.example.com$1.$2 [P] +</code></p></div> + +<p>Use of the [P] flag implies [L] - that is, the request is immediatly +pushed through the proxy, and any following rules will not be +considered.</p> + + + +<h3><a name="flag_pt" id="flag_pt">PT|passthrough</a></h3> + +<p> +The target (or substitution string) in a RewriteRule is assumed to be a +file path, by default. The use of the [PT] flag causes it to be treated +as a URI instead. That is to say, the +use of the [PT] flag causes the result of the <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> to be passed back through +URL mapping, so that location-based mappings, such as <code class="directive"><a href="../mod/mod_alias.html#alias">Alias</a></code>, for example, might have a chance to take +effect. +</p> + +<p> +If, for example, you have an +<code class="directive"><a href="../mod/mod_alias.html#alias">Alias</a></code> +for /icons, and have a <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> pointing there, you should +use the [PT] flag to ensure that the +<code class="directive"><a href="../mod/mod_alias.html#alias">Alias</a></code> is evaluated. +</p> + +<div class="example"><p><code> +Alias /icons /usr/local/apache/icons<br /> +RewriteRule /pics/(.+)\.jpg /icons/$1.gif [PT] +</code></p></div> + +<p> +Omission of the [PT] flag in this case will cause the Alias to be +ignored, resulting in a 'File not found' error being returned. +</p> + + + +<h3><a name="flag_qsa" id="flag_qsa">QSA|qsappend</a></h3> +<p> +When the replacement URI contains a query string, the default behavior +of <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> is to discard +the existing query string, and replace it with the newly generated one. +Using the [QSA] flag causes the query strings to be combined. +</p> + +<p>Consider the following rule:</p> + +<div class="example"><p><code> +RewriteRule /pages/(.+) /page.php?page=$1 [QSA] +</code></p></div> + +<p>With the [QSA] flag, a request for <code>/pages/123?one=two</code> will be +mapped to <code>/page.php?page=123&one=two</code>. Without the [QSA] +flag, that same request will be mapped to +<code>/page.php?page=123</code> - that is, the existing query string +will be discarded. +</p> + + +<h3><a name="flag_r" id="flag_r">R|redirect</a></h3> +<p> +Use of the [R] flag causes a HTTP redirect to be issued to the browser. +If a fully-qualified URL is specified (that is, including +<code>http://servername/</code>) then a redirect will be issued to that +location. Otherwise, the current servername will be used to generate the +URL sent with the redirect. +</p> + +<p> +A status code may be specified, in the range 300-399, with a 302 status +code being used by default if none is specified. +</p> + +<p> +You will almost always want to use [R] in conjunction with [L] (that is, +use [R,L]) because on its own, the [R] flag prepends +<code>http://thishost[:thisport]</code> to the URI, but then passes this +on to the next rule in the ruleset, which can often result in 'Invalid +URI in request' warnings. +</p> + + + +<h3><a name="flag_s" id="flag_s">S|skip</a></h3> +<p>The [S] flag is used to skip rules that you don't want to run. This +can be thought of as a <code>goto</code> statement in your rewrite +ruleset. In the following example, we only want to run the <code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> if the requested URI +doesn't correspond with an actual file.</p> + +<div class="example"><p><code> +# Is the request for a non-existent file? +RewriteCond %{REQUEST_FILENAME} !-f<br /> +RewriteCond %{REQUEST_FILENAME} !-d<br /> +# If so, skip these two RewriteRules +RewriteRule .? - [S=2]<br /> +<br /> +RewriteRule (.*\.gif) images.php?$1<br /> +RewriteRule (.*\.html) docs.php?$1 +</code></p></div> + +<p>This technique is useful because a <code class="directive"><a href="../mod/mod_rewrite.html#rewritecond">RewriteCond</a></code> only applies to the +<code class="directive"><a href="../mod/mod_rewrite.html#rewriterule">RewriteRule</a></code> immediately +following it. Thus, if you want to make a <code>RewriteCond</code> apply +to several <code>RewriteRule</code>s, one possible technique is to +negate those conditions and use a [Skip] flag.</p> + + + +<h3><a name="flag_t" id="flag_t">T|type</a></h3> +<p>Sets the MIME type with which the resulting response will be +sent. This has the same effect as the <code class="directive"><a href="../mod/mod_mime.html#addtype">AddType</a></code> directive.</p> + +<p>For example, you might use the following technique to serve Perl +source code as plain text, if requested in a particular way:</p> + +<div class="example"><p><code> +# Serve .pl files as plain text +RewriteRule \.pl$ - [T=text/plain] +</code></p></div> + +<p>Or, perhaps, if you have a camera that produces jpeg images without +file extensions, you could force those images to be served with the +correct MIME type by virtue of their file names:</p> + +<div class="example"><p><code> +# Files with 'IMG' in the name are jpg images.<br /> +RewriteRule IMG - [T=image/jpg] +</code></p></div> + +<p>Please note that this is a trivial example, and could be better done +using <code class="directive"><a href="../mod/core.html#filesmatch"><FilesMatch></a></code> +instead. Always consider the alternate +solutions to a problem before resorting to rewrite, which will +invariably be a less efficient solution than the alternatives.</p> + + +</div></div> +<div class="bottomlang"> +<p><span>Available Languages: </span><a href="../en/rewrite/rewrite_flags.html" title="English"> en </a></p> +</div><div id="footer"> +<p class="apache">Copyright 2008 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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