Apache::Registry should allow script to _only_ set return code

[Charles Levert]

Hi.

[ I use Apache 1.3.9 and mod_perl 1.21. ]

I believe that there is a difference between the following two
behaviors for an Apache module handler:

        -- setting the request's status field to a new value and also
        returning that value;

        -- just returning a value without assigning it to the
        request's status field.

It's an useful thing that a mod_perl script (what
Apache::Registry::handler calls) be able to decide that, e.g.,
HTTP_NOT_FOUND, should be returned to the browser and just return
then.

        # example mod_perl script

        use Apache::Constants ':response';
        my $r = Apache->request;

        if (...) {
                $r->status(NOT_FOUND);
                return;
        }

        $r->content_type('text/html');
        ...

We then expect that the normal ErrorDocument, as configured, should be
returned in that case.  However, this is not what happens because
Apache::Registry chooses the first behavior listed above and so an
HTTP_NOT_FOUND also seems to apply to the ErrorDocument then.  (This
is what Apache reports to the browser.)  The useful behavior would be
the second one listed above.

Ideally, a method such as $r->return_value could be defined,
independently of $r->status, and its argument could then be used when
Apache::Registry::handler returns.  An other possibility which can
probably be ruled out for compatibily with CGI scripts and existing
mod_perl script is to use the return value from the mod_perl script
itself.

I have appended a patch to Apache::Registry below which I believe to
be an acceptable solution for now.  (It really disallows a script to
set the status field, but uses the possibly changed status field as
return value instead and resets the status field to its original
value.)

Your comments are welcome.  Do you think that such a change or what I
mention above ($r->return_value) should make it in the main
distribution of mod_perl?


Charles


========================================================================
--- Registry.pm.orig-1.21       Tue Jan 12 21:56:34 1999
+++ Registry.pm Thu Jan 13 16:11:23 2000
@@ -131,6 +131,8 @@
            $Apache::Registry->{$package}{'mtime'} = $mtime;
        }
 
+       my $old_status = $r->status;
+
        my $cv = \&{"$package\::handler"};
        eval { &{$cv}($r, @_) } if $r->seqno;
        $r->chdir_file("$Apache::Server::CWD/");
@@ -155,7 +157,7 @@
 #              return REDIRECT;
 #          }
 #      }
-       return $r->status;
+       return $r->status($old_status);
     } else {
        return NOT_FOUND unless $Debug && $Debug & 2;
        return Apache::Debug::dump($r, NOT_FOUND);
========================================================================