Commit fe1d7dcc authored by Ralf S. Engelschall's avatar Ralf S. Engelschall
Browse files

Enhanced and cleaned up the URL rewriting engine for 1.3: 

First the grouped parts of RewriteRule pattern matches (parenthesis!) can be
accessed now via backreferences $1..$9 in RewriteConds test-against strings in
addition to RewriteRules subst string. Second the grouped parts of RewriteCond
pattern matches (parenthesis!) can be accessed now via backreferences %1..%9
both in following RewriteCond test-against strings and RewriteRules subst
string. This provides maximum flexibility through the use of backreferences.
Additionally the rewriting engine was cleaned up by putting common code to the
new expand_backrefs_inbuffer() function.

Submitted by:	Ralf S. Engelschall
Reviewed by:	Dean Gaudet, Ralf S. Engelschall


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@78903 13f79535-47bb-0310-9956-ffa450edef68
parent f41f7433

docs/manual/mod/mod_rewrite.html

+41 −12
Changes for docs/manual/mod/mod_rewrite.html: 41 added lines, 12 removed lines.
Original line number Diff line number Diff line
@@ -471,7 +471,34 @@ The following rewriting rule is only used if its pattern matches the current 
state of the URI <b>AND</b> if these additional conditions apply, too.



<p>

<em>TestString</em> is a string which contains server-variables of the form

<em>TestString</em> is a string which can contains the following

expanded constructs in addition to plain text:



<ul>

<li><b>RewriteRule backreferences</b>: These are backreferences of the form



<blockquote><strong>

<tt>$N</tt>

</strong></blockquote>



(1 <= N <= 9) which provide access to the grouped parts (parenthesis!) of the

pattern from the corresponding <tt>RewriteRule</tt> directive (the one

following the current bunch of <tt>RewriteCond</tt> directives).



<p>

<li><b>RewriteCond backreferences</b>: These are backreferences of the form



<blockquote><strong>

<tt>%N</tt>

</strong></blockquote>



(1 <= N <= 9) which provide access to the grouped parts (parenthesis!) of the

pattern from the last matched <tt>RewriteCond</tt> directive in the current

bunch of conditions.



<p>

<li><b>Server-Variables</b>: These are variables

    of the form



<blockquote><strong>

<tt>%{</tt> <em>NAME_OF_VARIABLE</em> <tt>}</tt>
@@ -554,7 +581,6 @@ IS_SUBREQ<br> 
</tr>

</table>





<p>

<table width="70%" border=0 bgcolor="#f0f0f0" cellspacing=0 cellpadding=10>

<tr><td>
@@ -564,6 +590,8 @@ system. 
</td></tr>

</table>



</ul>



<p>

Special Notes:

<ol>
@@ -796,7 +824,8 @@ which is substituted for (or replaces) the original URL for which 
<em>Pattern</em> matched.  Beside plain text you can use



<ol>

<li>pattern-group back-references (<code>$N</code>)

<li>back-references <code>$N</code> to the RewriteRule pattern

<li>back-references <code>%N</code> to the last matched RewriteCond pattern

<li>server-variables as in rule condition test-strings (<code>%{VARNAME}</code>)

<li><a href="#mapfunc">mapping-function</a> calls (<code>${mapname:key|default}</code>)

</ol>
@@ -1007,15 +1036,15 @@ comma-separated list of the following flags: 
    (This is <b>not</b> the same as the 'chain|C' flag!)

<p>

<li>'<strong><code>env|E=</code></strong><i>VAR</i>:<i>VAL</i>' (set <b>e</b>nvironment variable)<br>

    This forces an environment variable named <i>VAR</i> to be set to the value

    <i>VAL</i>, where <i>VAL</i> can contain regexp backreferences <tt>$N</tt>

    which will be expanded. You can use this flag more than once to set more

    than one variable. The variables can be later dereferenced at a lot of

    situations, but the usual location will be from within XSSI (via

        <tt>&lt;!--#echo var="VAR"--&gt;</tt>) or CGI (e.g. <tt>$ENV{'VAR'}</tt>).

        But additionally you can also dereference it in a following RewriteCond

        pattern via <tt>%{ENV:VAR}</tt>. Use this to strip but remember

        information from URLs.

	This forces an environment variable named <i>VAR</i> to be set to the

	value <i>VAL</i>, where <i>VAL</i> can contain regexp backreferences

	<tt>$N</tt> and <tt>%N</tt> which will be expanded. You can use this flag

	more than once to set more than one variable. The variables can be later

	dereferenced at a lot of situations, but the usual location will be from

	within XSSI (via <tt>&lt;!--#echo var="VAR"--&gt;</tt>) or CGI (e.g.

	<tt>$ENV{'VAR'}</tt>).  But additionally you can also dereference it in a

	following RewriteCond pattern via <tt>%{ENV:VAR}</tt>. Use this to strip

	but remember information from URLs.

</ul>



<p>