[RFC] Apache::HEADRegistry

[Geoffrey Young <ge...@modperlcookbook.org>]

well, thanks to Jean-Michel Hiver, we seem to have a winner with the
Apache::Registry HEAD request issue.

http://www.modperlcookbook.org/~geoff/modules/Apache-HEADRegistry-0.01.tar.gz

below is the README.  bascially, Apache::HEADRegistry is just a
subclass of Apache::Registry that is HEAD request aware - it lets you
go about your business as usual, but stops writes to the client short
of the actual content if the request is a HEAD request.  You ought to
be able to use it as a drop-in replacement for Apache::Registry, with
the usual caveats that come with Apache::RegistryNG over
Apache::Registry.

It seems fairly reasonable, but some additional smoke testing is
always much appreciated.  The only problem encountered so far seems to
be redirect scripts, such as 

use CGI;
$cgi = new CGI;
print $cgi->redirect ("http://www.foo.com/");

what happens here is that Apache itself processes the redirect as a
custom response and, due to some mod_perl shenanigans, doesn't respect
the r->header_only request.

so, what we seem to have here is a decent attempt at handling HEAD
requests, without altering mod_perl core, that works for all but
redirects (where the actual content is minimal).  as I said, additonal
tests are welcome - it's just a beginning effort.

I am also open to other naming schemes, since I hate naming things.

If folks like the idea, I may include an Apache::Test harness for the
module, if I find some spare tuits.

--Geoff

NAME 

Apache::HEADRegistry - Apache::Registry drop-in for HEAD requests

SYNOPSIS

httpd.conf:

 PerlModule Apache::HEADRegsitry

 <Location /perl-bin>
    SetHandler perl-script
    PerlHandler Apache::HEADRegistry

    Options +ExecCGI
    PerlSendHeader On
 </Location>  

DESCRIPTION

Apache::HEADRegistry is a drop-in for Apache::Registry that
properly handles HEAD requests.  Currently, Apache::Registry
has no handling of HEAD requests, so mod_cgi and Apache::Registry
scripts do not behave exactly the same.  This module attempts
to bridge that gap by intercepting headers much in the way
that mod_perl does, but then obeying the value of $r->header_only.

NOTES

Apache::HEADRegistry is a subclass of Apache::RegistryNG, which
means that it doesn't behave _exactly_ the same as Apache::Registry.
Namely, it uses the filename of the script to determine the 
unique package namespace, whereas Apache::Registry uses the URI.
HEADRegistry also does not do any of the auto-dereferencing in its
print() method - if you want that type of thing, then you are
obviously relying on the mod_perl API yourself and can therefore
check $r->header_only yourself.  This module is meant for those
who want mod_cgi emulation only.

FEATURES/BUGS

No known bugs or features at this time, but consider this module
alphaware.

SEE ALSO

perl(1), mod_perl(3), Apache(3), Apache::Registry(3), 
Apache::RegistryNG

AUTHOR

Geoffrey Young <ge...@modperlcookbook.org>

COPYRIGHT

Copyright (c) 2002, Geoffrey Young.
All rights reserved.

This module is free software.  It may be used, redistributed
and/or modified under the same terms as Perl itself.

HISTORY

This code is derived in part from examples in the 
"The mod_perl Developer's Cookbook"

For more information, visit http://www.modperlcookbook.org/

It also contains code lifted from various mod_perl internal
sources, such as Apache.pm and mod_perl.c, and LWP.  Thanks
all for being good open source contributors.