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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> |
| <sourcefile>mod_proxy_scgi.c</sourcefile> |
| <identifier>proxy_scgi_module</identifier> |
| <compatibility>Available in version 2.2.14 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> |
| <highlight language="config"> |
| ProxyPass /scgi-bin/ scgi://localhost:4000/ |
| </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</title> |
| <highlight language="config"> |
| ProxyPass "/scgi-bin/" "balancer://somecluster/" |
| <Proxy "balancer://somecluster"> |
| BalancerMember "scgi://localhost:4000" |
| BalancerMember "scgi://localhost:4001" |
| </Proxy> |
| </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>, an <dfn>environment |
| variable</dfn> may also control the SCGI protocol |
| provider:</p> |
| <dl> |
| <dt>proxy-scgi-pathinfo</dt> |
| <dd>By default <module>mod_proxy_scgi</module> will neither create |
| nor export the <var>PATH_INFO</var> environment variable. This allows |
| the backend SCGI 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_scgi</module> to generate |
| a "best guess" for <var>PATH_INFO</var>, set this env-var. The |
| variable must be set before <directive module="env">SetEnv</directive> |
| is effective. <directive module="setenv">SetEnvIf</directive> can be |
| used instead: <code>SetEnvIf Request_URI . proxy-scgi-pathinfo</code> |
| </dd> |
| </dl> |
| </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 be served directly by the gateway. This is useful |
| for performance purposes — httpd can use <code>sendfile</code> or other |
| optimizations, which are not possible if the file comes over the backend |
| socket. Additionally, the file contents are not transmitted twice.</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 the filename to serve. |
| The header is removed from the final response headers. This is equivalent to |
| <code>ProxySCGISendfile X-Sendfile</code>.</dd> |
| |
| <dt>anything else</dt> |
| <dd>Similar to <code>On</code>, but instead of the hardcoded header name |
| <code>X-Sendfile</code>, the argument is used as the header name.</dd> |
| </dl> |
| |
| <example><title>Example</title> |
| <highlight language="config"> |
| # Use the default header (X-Sendfile) |
| ProxySCGISendfile On |
| |
| # Use a different header |
| ProxySCGISendfile X-Send-Static |
| </highlight> |
| </example> |
| </usage> |
| </directivesynopsis> |
| |
| <directivesynopsis> |
| <name>ProxySCGIInternalRedirect</name> |
| <description>Enable or disable internal redirect responses from the |
| backend</description> |
| <syntax>ProxySCGIInternalRedirect On|Off|<var>Headername</var></syntax> |
| <default>ProxySCGIInternalRedirect On</default> |
| <contextlist><context>server config</context><context>virtual host</context> |
| <context>directory</context></contextlist> |
| <compatibility>The <var>Headername</var> feature is available in version |
| 2.4.13 and later</compatibility> |
| |
| <usage> |
| <p>The <directive>ProxySCGIInternalRedirect</directive> enables the backend |
| to internally redirect the gateway to a different URL. This feature |
| originates 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> (or configured alternate |
| header) and its value starts with a slash (<code>/</code>). This value is |
| interpreted as a new local URL that Apache httpd 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 or specify the use of a header other than <code>Location</code>.</p> |
| |
| <example><title>Example</title> |
| <highlight language="config"> |
| ProxySCGIInternalRedirect Off |
| |
| # Django and some other frameworks will fully qualify "local URLs" |
| # set by the application, so an alternate header must be used. |
| <Location /django-app/> |
| ProxySCGIInternalRedirect X-Location |
| </Location> |
| </highlight> |
| </example> |
| </usage> |
| </directivesynopsis> |
| |
| </modulesynopsis> |