Add docs for WSGIMapHEADToGET directive.

Author: GrahamDumpleton

docs/configuration-directives/WSGIMapHEADToGET.rst

@@ -0,0 +1,23 @@
+==================
+WSGIMapHEADToGET
+==================
+
+:Description: Enable/disable mapping of HEAD request to GET.
+:Syntax: ``WSGIMapHEADToGET On|Off|Auto``
+:Default: ``WSGIMapHEADToGET Auto``
+:Context: server config, virtual host, directory, .htaccess
+
+The ``WSGIMapHEADToGET`` directive controls the behaviour of automatically
+mapping any ``HEAD`` request to a ``GET`` request when an Apache output filter
+is registered that may want to see the complete response in order to generate
+correct response headers.
+
+The directive can be set to be either ``Auto`` (the default), ``On`` which
+will always map a ``HEAD`` to ``GET`` even if no output filters detected and
+``Off`` to always preserve the original request method type.
+
+The directive may be required where a WSGI application tries to optimize and
+avoid doing work for a ``HEAD`` request by not actually generating a response
+so that complete response headers can still be generated. By doing this the
+WSGI application can break Apache filters for caching, so the mapping of
+``HEAD`` to ``GET`` can be required to avoid problems.

docs/configuration.rst

@@ -17,6 +17,7 @@ Configuration
    configuration-directives/WSGIDestroyInterpreter
    configuration-directives/WSGIImportScript
    configuration-directives/WSGILazyInitialization
+   configuration-directives/WSGIMapHEADToGET
    configuration-directives/WSGIPassAuthorization
    configuration-directives/WSGIProcessGroup
    configuration-directives/WSGIPythonEggs