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<modulesynopsis metafile="mod_proxy_fcgi.xml.meta">

<name>mod_proxy_fcgi</name>
<description>FastCGI support module for
<module>mod_proxy</module></description>
<status>Extension</status>
<sourcefile>mod_proxy_fcgi.c</sourcefile>
<identifier>proxy_fcgi_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://www.fastcgi.com/">FastCGI</a> protocol.</p>

    <p>Thus, in order to get the ability of handling the <code>FastCGI</code>
    protocol, <module>mod_proxy</module> and
    <module>mod_proxy_fcgi</module> have to be present in the server.</p>

    <p>Unlike <a href="http://httpd.apache.org/mod_fcgid/">mod_fcgid</a>
    and <a href="http://www.fastcgi.com/">mod_fastcgi</a>,
    <module>mod_proxy_fcgi</module> has no provision for starting the
    application process; <program>fcgistarter</program> is provided
    (on some platforms) for that purpose. Alternatively, external launching
    or process management may be available in the FastCGI application
    framework in use.</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><program>fcgistarter</program></seealso>
<seealso><module>mod_proxy</module></seealso>
<seealso><module>mod_authnz_fcgi</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_fcgi</module>.</p>

    <example><title>Single application instance</title>
    <highlight language="config">
ProxyPass "/myapp/" "fcgi://localhost:4000/"
    </highlight>
    </example>

    <p> <module>mod_proxy_fcgi</module> disables connection reuse by
    default, so after a request has been completed the connection will NOT be
    held open by that httpd child process and won't be reused.  If the
    FastCGI application is able to handle concurrent connections
    from httpd, you can opt-in to connection reuse as shown in the following
    example:</p>

    <example><title>Single application instance, connection reuse (2.4.11 and later)</title>
    <highlight language="config">
ProxyPass "/myapp/" "fcgi://localhost:4000/" enablereuse=on
    </highlight>
    </example>

    <p> The following example passes the request URI as a filesystem
    path for the PHP-FPM daemon to run. The request URL is implicitly added
    to the 2nd parameter. The hostname and port following fcgi:// are where
    PHP-FPM is listening.  Connection pooling is enabled.</p>
    <example><title>PHP-FPM</title>
    <highlight language="config">
ProxyPassMatch "^/myapp/.*\.php(/.*)?$" "fcgi://localhost:9000/var/www/" enablereuse=on
    </highlight>
    </example>

    <p> The following example passes the request URI as a filesystem
    path for the PHP-FPM daemon to run. In this case, PHP-FPM is listening on
    a unix domain socket (UDS).  Requires 2.4.9 or later. With this syntax,
    the hostname and optional port following fcgi:// are ignored.</p>
    <example><title>PHP-FPM with UDS</title>
    <highlight language="config">
# UDS does not currently support connection reuse
ProxyPassMatch "^/(.*\.php(/.*)?)$" "unix:/var/run/php5-fpm.sock|fcgi://localhost/var/www/"
    </highlight>
    </example>

    <p>The balanced gateway needs <module>mod_proxy_balancer</module> and
    at least one load balancer algorithm module, such as
    <module>mod_lbmethod_byrequests</module>, in addition to the proxy
    modules listed above.  <module>mod_lbmethod_byrequests</module> is the
    default, and will be used for this example configuration.</p>

    <example><title>Balanced gateway to multiple application instances</title>
    <highlight language="config">
ProxyPass "/myapp/" "balancer://myappcluster/"
&lt;Proxy "balancer://myappcluster/"&gt;
    BalancerMember "fcgi://localhost:4000"
    BalancerMember "fcgi://localhost:4001"
&lt;/Proxy&gt;
    </highlight>
    </example>

      <p>You can also force a request to be handled as a reverse-proxy
        request, by creating a suitable Handler pass-through. The example
        configuration below will pass all requests for PHP scripts to the
        specified FastCGI server using reverse proxy.
        This feature is available in Apache HTTP Server 2.4.10 and later. For performance
       reasons, you will want to define a <a href="mod_proxy.html#workers">worker</a>
       representing the same fcgi:// backend. The benefit of this form is that it
       allows the normal mapping of URI to filename to occur in the server, and the
       local filesystem result is passed to the backend.  When FastCGI is
       configured this way, the server can calculate the most accurate
       PATH_INFO.
      </p>
    <example><title>Proxy via Handler</title>
      <highlight language="config">
&lt;FilesMatch "\.php$"&gt;
    # Note: The only part that varies is /path/to/app.sock
    SetHandler  "proxy:unix:/path/to/app.sock|fcgi://localhost/"
&lt;/FilesMatch&gt;

# Define a matching worker.
# The part that is matched to the SetHandler is the part that
# follows the pipe. If you need to distinguish, "localhost; can
# be anything unique.
&lt;Proxy "fcgi://localhost/" enablereuse=on max=10&gt;
&lt;/Proxy&gt;

&lt;FilesMatch ...&gt;
    SetHandler  "proxy:fcgi://localhost:9000"
&lt;/FilesMatch&gt;

&lt;FilesMatch ...&gt;
    SetHandler  "proxy:balancer://myappcluster/"
&lt;/FilesMatch&gt;
      </highlight>
   </example>
</section>

<section id="env"><title>Environment Variables</title>
    <p>In addition to the configuration directives that control the
    behaviour of <module>mod_proxy</module>, there are a number of
    <dfn>environment variables</dfn> that control the FCGI protocol
    provider:</p>
    <dl>
        <dt>proxy-fcgi-pathinfo</dt>
        <dd>When configured via <directive module="mod_proxy"
        >ProxyPass</directive> or  <directive module="mod_proxy"
        >ProxyPassMatch</directive>, <module>mod_proxy_fcgi</module> will not
        set the <var>PATH_INFO</var> environment variable. This allows
        the backend FCGI server to correctly determine <var>SCRIPT_NAME</var>
        and <var>Script-URI</var> and be compliant with RFC 3875 section 3.3.
        If instead you need <module>mod_proxy_fcgi</module> to generate
        a "best guess" for <var>PATH_INFO</var>, set this env-var.
        This is a workaround for a bug in some FCGI implementations.  This
        variable can be set to multiple values to tweak at how the best guess
        is chosen (In 2.4.11 and later only):
        <dl>
          <dt>first-dot</dt>
          <dd>PATH_INFO is split from the slash following the
              <em>first</em> "." in the URL.</dd>
          <dt>last-dot</dt>
          <dd>PATH_INFO is split from the slash following the
              <em>last</em> "." in the URL.</dd>
          <dt>full</dt>
          <dd>PATH_INFO is calculated by an attempt to map the URL to the
              local filesystem.</dd>
          <dt>unescape</dt>
          <dd>PATH_INFO is the path component of the URL, unescaped /
              decoded.</dd>
          <dt>any other value</dt>
          <dd>PATH_INFO is the same as the path component of the URL.
              Originally, this was the only proxy-fcgi-pathinfo option.</dd>
         </dl>
        </dd>
    </dl>
</section>

</modulesynopsis>
