mod_proxy_scgi.xml revision 9f07b6dc343a4e3eba5f4c47050a77441723ce89
<?xml version="1.0"?>
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<modulesynopsis metafile="mod_proxy_scgi.xml.meta">
<name>mod_proxy_scgi</name>
<description>SCGI gateway module for <module>mod_proxy</module></description>
<status>Extension</status>
<identifier>proxy_scgi_module</identifier>
<compatibility>Available in version 2.3 and later</compatibility>
<summary>
<p>This module <em>requires</em> the service of <module
>mod_proxy</module>. It provides support for the
<a href="http://python.ca/scgi/protocol.txt">SCGI protocol, version
1</a>.</p>
<p>Thus, in order to get the ability of handling the SCGI protocol,
<module>mod_proxy</module> and <module>mod_proxy_scgi</module> have to
be present in the server.</p>
<note type="warning"><title>Warning</title>
<p>Do not enable proxying until you have <a
href="mod_proxy.html#access">secured your server</a>. Open proxy
servers are dangerous both to your network and to the Internet at
large.</p>
</note>
</summary>
<seealso><module>mod_proxy</module></seealso>
<seealso><module>mod_proxy_balancer</module></seealso>
<section id="examples"><title>Examples</title>
<p>Remember, in order to make the following examples work, you have to
enable <module>mod_proxy</module> and <module>mod_proxy_scgi</module>.</p>
<example><title>Simple gateway</title>
ProxyPass /scgi-bin/ scgi://localhost:4000/
</example>
<p>The balanced gateway needs <module>mod_proxy_balancer</module> in
addition to the already mentioned proxy modules.</p>
<example><title>Balanced gateway</title>
ProxyPass /scgi-bin/ balancer://somecluster/<br />
<Proxy balancer://somecluster/><br />
<indent>
BalancerMember scgi://localhost:4000/<br />
BalancerMember scgi://localhost:4001/<br />
</indent>
</Proxy>
</example>
</section>
<directivesynopsis>
<name>ProxySCGISendfile</name>
<description>Enable evaluation of <var>X-Sendfile</var> pseudo response
header</description>
<syntax>ProxySCGISendfile On|Off|<var>Headername</var></syntax>
<default>ProxySCGISendfile Off</default>
<contextlist><context>server config</context><context>virtual host</context>
<context>directory</context></contextlist>
<usage>
<p>The <directive>ProxySCGISendfile</directive> directive enables the
SCGI backend to let files serve directly by the gateway. This is useful
performance purposes -- the httpd can use <code>sendfile</code> or other
optimizations, which are not possible if the file comes over the backend
socket.</p>
<p>The <directive>ProxySCGISendfile</directive> argument determines the
gateway behaviour:</p>
<dl>
<dt><code>Off</code></dt>
<dd>No special handling takes place.</dd>
<dt><code>On</code></dt>
<dd>The gateway looks for a backend response header called
<code>X-Sendfile</code> and interprets the value as filename to serve. The
header is removed from the final response headers. This is equivalent to
<code>ProxySCGIRequest X-Sendfile</code>.</dd>
<dt>anything else</dt>
<dd>Similar to <code>On</code>, but instead of the hardcoded header name
the argument is applied as header name.</dd>
</dl>
<example><title>Example</title>
# Use the default header (X-Sendfile)<br />
ProxySCGISendfile On<br />
<br />
# Use a different header<br />
ProxySCGISendfile X-Send-Static
</example>
</usage>
</directivesynopsis>
<directivesynopsis>
<name>ProxySCGIInternalRedirect</name>
<description>Enable or disable internal redirect responses from the
backend</description>
<syntax>ProxySCGIInternalRedirect On|Off</syntax>
<default>ProxySCGIInternalRedirect On</default>
<contextlist><context>server config</context><context>virtual host</context>
<context>directory</context></contextlist>
<usage>
<p>The <directive>ProxySCGIInternalRedirect</directive> enables the backend
to internally redirect the gateway to a different URL. This feature
origins in <module>mod_cgi</module>, which internally redirects the
response, if the response status is <code>OK</code> (<code>200</code>) and
the response contains a <code>Location</code> header and its value starts
with a slash (<code>/</code>). This value is interpreted as a new local
URL the apache internally redirects to.</p>
<p><module>mod_proxy_scgi</module> does the same as
<module>mod_cgi</module> in this regard, except that you can turn off the
feature.</p>
<example><title>Example</title>
ProxySCGIInternalRedirect Off
</example>
</usage>
</directivesynopsis>
</modulesynopsis>