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Posted to cvs@httpd.apache.org by sl...@apache.org on 2002/02/14 01:48:39 UTC
cvs commit: httpd-2.0/docs/manual/mod mod_setenvif.xml
slive 02/02/13 16:48:39
Added: docs/manual/mod mod_setenvif.xml
Log:
Add the first xml doc.
Revision Changes Path
1.1 httpd-2.0/docs/manual/mod/mod_setenvif.xml
Index: mod_setenvif.xml
===================================================================
<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="../style/manual.xsl"?>
<modulesynopsis>
<name>mod_setenvif</name>
<status>Base</status>
<identifier>setenvif_module</identifier>
<sourcefile>mod_setenvif.c</sourcefile>
<compatibility>Available in Apache 1.3 and later</compatibility>
<description>Allows the setting of environment variables based
on characteristics of the request</description>
<summary>
<p>The <module>mod_setenvif</module> module allows you to set
environment variables according to whether different aspects of
the request match regular expressions you specify. These
environment variables can be used by other parts of the server
to make decisions about actions to be taken.</p>
<p>The directives are considered in the order they appear in
the configuration files. So more complex sequences can be used,
such as this example, which sets <code>netscape</code> if the
browser is mozilla but not MSIE.</p>
<example>
BrowserMatch ^Mozilla netscape<br />
BrowserMatch MSIE !netscape<br />
</example>
</summary>
<seealso><a href="../env.html">Environment Variables in Apache</a></seealso>
<directivesynopsis>
<name>BrowserMatch</name>
<description>Sets environment variables conditional on HTTP User-Agent
</description>
<syntax>BrowserMatch <em>regex env-variable</em>[=<em>value</em>]
[<em>env-variable</em>[=<em>value</em>]] ...</syntax>
<default><i>none</i></default>
<context>server config, virtual host, directory, .htaccess</context>
<override>FileInfo</override>
<compatibility>Apache 1.2 and
above (in Apache 1.2 this directive was found in the
now-obsolete mod_browser module)</compatibility>
<usage>
<p>The <directive>BrowserMatch</directive> directive defines
environment variables based on the <code>User-Agent</code> HTTP
request header field. The first argument should be a POSIX.2
extended regular expression (similar to an
<code>egrep</code>-style regex). The rest of the arguments give
the names of variables to set, and optionally values to which they
should be set. These take the form of</p>
<ol>
<li><code><em>varname</em></code>, or</li>
<li><code>!<em>varname</em></code>, or</li>
<li><code><em>varname</em>=<em>value</em></code></li>
</ol>
<p>In the first form, the value will be set to "1". The second
will remove the given variable if already defined, and the
third will set the variable to the value given by
<code><em>value</em></code>. If a <code>User-Agent</code>
string matches more than one entry, they will be merged.
Entries are processed in the order in which they appear, and
later entries can override earlier ones.</p>
<p>For example:</p>
<example>
BrowserMatch ^Mozilla forms jpeg=yes browser=netscape<br />
BrowserMatch "^Mozilla/[2-3]" tables agif frames javascript<br />
BrowserMatch MSIE !javascript<br />
</example>
<p>Note that the regular expression string is
<strong>case-sensitive</strong>. For case-INsensitive matching,
see the <directive
module="mod_setenvif">BrowserMatchNoCase</directive>
directive.</p>
<p>The <directive>BrowserMatch</directive> and
<directive>BrowserMatchNoCase</directive> directives are special cases of
the <directive module="mod_setenvif">SetEnvIf</directive> and <directive
module="mod_setenvif">SetEnvIfNoCase</directive>
directives. The following two lines have the same effect:</p>
<example>
BrowserMatchNoCase Robot is_a_robot<br />
SetEnvIfNoCase User-Agent Robot is_a_robot<br />
</example>
</usage>
</directivesynopsis>
<directivesynopsis>
<name>BrowserMatchNoCase</name>
<description>Sets environment variables conditional on User-Agent without
respect to case</description>
<syntax>BrowserMatchNoCase <em>regex env-variable</em>[=<em>value</em>]
[<em>env-variable</em>[=<em>value</em>]] ...</syntax>
<default><em>none</em></default>
<context>server config, virtual host, directory, .htaccess</context>
<override>FileInfo</override>
<compatibility>Apache 1.2 and
above (in Apache 1.2 this directive was found in the
now-obsolete mod_browser module)</compatibility>
<usage>
<p>The <directive>BrowserMatchNoCase</directive> directive is
semantically identical to the <directive
module="mod_setenvif">BrowserMatch</directive> directive.
However, it provides for case-insensitive matching. For
example:</p>
<example>
BrowserMatchNoCase mac platform=macintosh<br />
BrowserMatchNoCase win platform=windows<br />
</example>
<p>The <directive>BrowserMatch</directive> and
<directive>BrowserMatchNoCase</directive> directives are special cases of
the <directive module="mod_setenvif">SetEnvIf</directive> and <directive
module="mod_setenvif">SetEnvIfNoCase</directive>
directives. The following two lines have the same effect:</p>
<example>
BrowserMatchNoCase Robot is_a_robot<br />
SetEnvIfNoCase User-Agent Robot is_a_robot<br />
</example>
</usage>
</directivesynopsis>
<directivesynopsis>
<name>SetEnvIf</name>
<description>Sets environment variables based on attributes of the request
</description>
<syntax>SetEnvIf <em>attribute
regex env-variable</em>[=<em>value</em>]
[<em>env-variable</em>[=<em>value</em>]] ...</syntax>
<default><em>none</em></default>
<context> server config, virtual host, directory, .htaccess</context>
<override>FileInfo</override>
<compatibility>Apache 1.3 and
above; the Request_Protocol keyword and environment-variable
matching are only available with 1.3.7 and later</compatibility>
<usage>
<p>The <directive>SetEnvIf</directive> directive defines environment
variables based on attributes of the request. These attributes
can be the values of various HTTP request header fields (see <a
href="http://www.rfc-editor.org/rfc/rfc2616.txt">RFC2616</a>
for more information about these), or of other aspects of the
request, including the following:</p>
<ul>
<li><code>Remote_Host</code> - the hostname (if available) of
the client making the request</li>
<li><code>Remote_Addr</code> - the IP address of the client
making the request</li>
<li><code>Remote_User</code> - the authenticated username (if
available)</li>
<li><code>Request_Method</code> - the name of the method
being used (<code>GET</code>, <code>POST</code>, <em>et
cetera</em>)</li>
<li><code>Request_Protocol</code> - the name and version of
the protocol with which the request was made (<em>e.g.</em>,
"HTTP/0.9", "HTTP/1.1", <em>etc.</em>)</li>
<li><code>Request_URI</code> - the portion of the URL
following the scheme and host portion</li>
</ul>
<p>Some of the more commonly used request header field names
include <code>Host</code>, <code>User-Agent</code>, and
<code>Referer</code>.</p>
<p>If the <em>attribute</em> name doesn't match any of the
special keywords, nor any of the request's header field names,
it is tested as the name of an environment variable in the list
of those associated with the request. This allows
<directive>SetEnvIf</directive> directives to test against the result of
prior matches.</p>
<note>
<strong>Only those environment variables defined by earlier
<code>SetEnvIf[NoCase]</code> directives are available for
testing in this manner. 'Earlier' means that they were
defined at a broader scope (such as server-wide) or
previously in the current directive's scope.</strong>
</note>
<p><em>attribute</em> may be a regular expression when used to
match a request header. If <em>attribute</em> is a regular
expression and it doesn't match any of the request's header
names, then <em>attribute</em> is not tested against the
request's environment variable list.</p>
<example>
<title>Example:</title>
SetEnvIf Request_URI "\.gif$" object_is_image=gif<br />
SetEnvIf Request_URI "\.jpg$" object_is_image=jpg<br />
SetEnvIf Request_URI "\.xbm$" object_is_image=xbm<br />
:<br />
SetEnvIf Referer www\.mydomain\.com intra_site_referral<br />
:<br />
SetEnvIf object_is_image xbm XBIT_PROCESSING=1<br />
:<br />
SetEnvIf ^TS* ^[a-z].* HAVE_TS<br />
</example>
<p>The first three will set the environment variable
<code>object_is_image</code> if the request was for an image
file, and the fourth sets <code>intra_site_referral</code> if
the referring page was somewhere on the
<code>www.mydomain.com</code> Web site.</p>
<p>The last example will set environment variable
<code>HAVE_TS</code> if the request contains any headers that
begin with "TS" whose values begins with any character in the
set [a-z].</p>
</usage>
</directivesynopsis>
<directivesynopsis>
<name>SetEnvIfNoCase</name>
<description>Sets environment variables based on attributes of the request
without respect to case</description>
<syntax>SetEnvIfNoCase <em>attribute regex env-variable</em>[=<em>value</em>]
[<em>env-variable</em>[=<em>value</em>]] ...</syntax>
<default><em>none</em></default>
<context>server config, virtual host, directory, .htaccess</context>
<override>FileInfo</override>
<compatibility>Apache 1.3 and above</compatibility>
<usage>
<p>The <directive>SetEnvIfNoCase</directive> is semantically identical to
the <directive module="mod_setenvif">SetEnvIf</directive> directive,
and differs only in that the regular expression matching is
performed in a case-insensitive manner. For example:</p>
<example>
SetEnvIfNoCase Host Apache\.Org site=apache
</example>
<p>This will cause the <code>site</code> environment variable
to be set to "<code>apache</code>" if the HTTP request header
field <code>Host:</code> was included and contained
<code>Apache.Org</code>, <code>apache.org</code>, or any other
combination.</p>
</usage>
</directivesynopsis>
</modulesynopsis>