Apache HTTP Server Version 2.2

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# Apache Module mod_substitute

Available Languages: en

Description: | Perform search and replace operations on response bodies
Status: | Extension
Module Identifier: | substitute_module
Source File: | mod_substitute.c
Compatibility: | Available in Apache 2.2.7 and later

### Summary

`mod_substitute` provides a mechanism to perform both regular expression and fixed string substitutions on response bodies.

### Directives

- Comments

## Substitute Directive

Description: | Pattern to filter the response content
Syntax: | `Substitute s/pattern/substitution/[infq]`
Context: | directory, .htaccess
Override: | FileInfo
Status: | Extension
Module: | mod_substitute

The `Substitute` directive specifies a search and replace pattern to apply to the response body.

The meaning of the pattern can be modified by using any combination of these flags:

`i`
  Perform a case-insensitive match.
`n`
  By default the pattern is treated as a regular expression. Using the `n` flag forces the pattern to be treated as a fixed string.
`f`
  The `f` flag causes mod_substitute to flatten the result of a substitution allowing for later substitutions to take place on the boundary of this one. This is the default.
`q`
  The `q` flag causes mod_substitute to not flatten the buckets after each substitution. This can result in much faster response and a decrease in memory utilization, but should only be used if there is no possibility that the result of one substitution will ever match a pattern or regex of a subsequent one.

### Example

`<Location /> AddOutputFilterByType SUBSTITUTE text/html
Substitute s/foo/bar/ni
</Location>`

If either the pattern or the substitution contain a slash character then an alternative delimiter should be used:

### Example of using an alternate delimiter

`<Location /> AddOutputFilterByType SUBSTITUTE text/html
Substitute "s|<BR */?>|<br />|i" </Location>`

## SubstituteInheritBefore Directive

Description: | Change the merge order of inherited patterns
Syntax: | `SubstituteInheritBefore on|off`
Default: | `SubstituteInheritBefore off`
Context: | directory, .htaccess
Override: | FileInfo
Status: | Extension
Module: | mod_substitute
Compatibility: | Available in httpd 2.2.32 and later

Whether to apply the inherited `Substitute` patterns first (`on`), or after the ones of the current context (`off`). `SubstituteInheritBefore` is itself inherited, hence contexts that inherit it (those that don't specify their own `SubstituteInheritBefore` value) will apply the closest defined merge order.

Available Languages: en

## Comments

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