mod_reflector Reflect a request body as a response via the output filter stack. Base mod_reflector.c reflector_module Version 2.3 and later

This module allows request bodies to be reflected back to the client, in the process passing the request through the output filter stack. A suitably configured chain of filters can be used to transform the request into a response. This module can be used to turn an output filter into an HTTP service.
Examples
Compression service
Pass the request body through the DEFLATE filter to compress the body. This request requires a Content-Encoding request header containing "gzip" for the filter to return compressed data. <Location "/compress"> SetHandler reflector SetOutputFilter DEFLATE </Location>
Image downsampling service
Pass the request body through an image downsampling filter, and reflect the results to the caller. <Location "/downsample"> SetHandler reflector SetOutputFilter DOWNSAMPLE </Location>
ReflectorHeader Reflect an input header to the output headers ReflectorHeader inputheader [outputheader] server configvirtual host directory.htaccess Options

This directive controls the reflection of request headers to the response. The first argument is the name of the request header to copy. If the optional second argument is specified, it will be used as the name of the response header, otherwise the original request header name will be used.