# 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.
-<Proxy fcgi://localhost/ enablereuse=on max=10>
+<Proxy "fcgi://localhost/" enablereuse=on max=10>
</Proxy>
<FilesMatch ...>
<contextlist><context>server config</context>
<context>virtual host</context><context>directory</context>
<context>.htaccess</context></contextlist>
-<compatibility>Available in version 2.5 and later</compatibility>
+<override>FileInfo</override>
+<compatibility>Available in version 2.4.26 and later</compatibility>
<usage>
<p>This directive allows the type of backend FastCGI application to be
specified. Some FastCGI servers, such as PHP-FPM, use historical quirks of
environment variables to identify the type of proxy server being used. Set
-this direcive to "GENERIC" if your non PHP-FPM application has trouble
+this directive to "GENERIC" if your non PHP-FPM application has trouble
interpreting environment variables such as SCRIPT_FILENAME or PATH_TRANSLATED
as set by the server.</p>
PHP-FPM would strip the prefix then remember it was talking to Apache. In
2.4.21 through 2.4.25, this prefix was automatically stripped by the server,
breaking the ability of PHP-FPM to detect and interoperate with Apache in some
-scenarios.</p>
+scenarios.</p>
</usage>
</directivesynopsis>
<name>ProxyFCGISetEnvIf</name>
<description>Allow variables sent to FastCGI servers to be fixed up</description>
<syntax>ProxyFCGISetEnvIf <var>conditional-expression</var>
- <var>environment-variable-name</var>
- <var>value-expression</var></syntax>
+ [!]<var>environment-variable-name</var>
+ [<var>value-expression</var>]</syntax>
<contextlist><context>server config</context>
<context>virtual host</context><context>directory</context>
<context>.htaccess</context></contextlist>
-<compatibility>Available in version 2.5 and later</compatibility>
+<override>FileInfo</override>
+<compatibility>Available in version 2.4.26 and later</compatibility>
<usage>
<p>Just before passing a request to the configured FastCGI server, the core of
<li>PATH_TRANSLATED</li>
</ul>
-<p>This directive allows the environment variables above, or any others of
+<p>This directive allows the environment variables above, or any others of
interest, to be overridden. This directive is evaluated after the initial
values for these variables are set, so they can be used as input into both
the condition expressions and value expressions.</p>
<p>Parameter syntax:</p>
<dl>
-<dt>conditional-expression</dt>
-<dd>Specifies an expression that controls whether the environmen variable that
- follows will be modified. For information on the expression syntax, see
- the examples that follow or the full specification at the
+<dt>conditional-expression</dt>
+<dd>Specifies an expression that controls whether the environment variable that
+ follows will be modified. For information on the expression syntax, see
+ the examples that follow or the full specification at the
<a href="../expr.html">ap_expr</a> documentation.
</dd>
-<dt>environment-variable-name</dt>
+<dt>environment-variable-name</dt>
<dd> Specifies the CGI environment variable to change,
- such as PATH_INFO.</dd>
+ such as PATH_INFO. If preceded by an exclamation point, the variable
+ will be unset.</dd>
<dt>value-expression</dt>
-<dd>Specifies the replacement value for the preceding environment variable. Backreferences, such as "$1",
-can be included from regular expression captures in <var>conditional-expression</var></dd>
+<dd>Specifies the replacement value for the preceding environment variable.
+ Backreferences, such as "$1", can be included from regular expression
+ captures in <var>conditional-expression</var>. If omitted, the variable is
+ set (or overridden) to an empty string — but see the Note below.</dd>
</dl>
-
+
<example>
-# A basic, unconditional override<br/>
-ProxyFCGISetEnvIf "true" PATH_INFO "/example"<br/>
-<br/>
-# Use an environment variable in the value<br/>
-ProxyFCGISetEnvIf "true" PATH_INFO "%{reqenv:SCRIPT_NAME}"<br/>
-<br/>
-# Use captures in the conditions and backreferences in the replacement<br/>
-ProxyFCGISetEnvIf "reqenv('PATH_TRANSLATED') =~ m#(/.*prefix)(\d+)(.*)#" PATH_TRANSLATED "$1$3"<br/>
+ <highlight language="config">
+# A basic, unconditional override
+ProxyFCGISetEnvIf "true" PATH_INFO "/example"
+
+# Use an environment variable in the value
+ProxyFCGISetEnvIf "true" PATH_INFO "%{reqenv:SCRIPT_NAME}"
+
+# Use captures in the conditions and backreferences in the replacement
+ProxyFCGISetEnvIf "reqenv('PATH_TRANSLATED') =~ m|(/.*prefix)(\d+)(.*)|" PATH_TRANSLATED "$1$3"
+ </highlight>
</example>
+<note><title>Note: Unset vs. Empty</title>
+ The following will unset <code>VARIABLE</code>, preventing it from being sent
+ to the FastCGI server:
+
+ <highlight language="config">ProxyFCGISetEnvIf true !VARIABLE</highlight>
+
+ Whereas the following will erase any existing <em>value</em> of
+ <code>VARIABLE</code> (by setting it to the empty string), but the empty
+ <code>VARIABLE</code> will still be sent to the server:
+
+ <highlight language="config">ProxyFCGISetEnvIf true VARIABLE</highlight>
+
+ The CGI/1.1 specification
+ <a href="https://tools.ietf.org/html/rfc3875#section-4.1">does not
+ distinguish</a> between a variable with an empty value and a variable that
+ does not exist. However, many CGI and FastCGI implementations distinguish (or
+ allow scripts to distinguish) between the two. The choice of which to use is
+ dependent upon your implementation and your reason for modifying the variable.
+</note>
+
</usage>
</directivesynopsis>
projects / apache / blobdiff