[cups] cups filter to decompress jobs before spooling/acceptance?

[Tim Mooney]

All-

I have lots of experience with printing, but I'm relatively new to using
CUPS in a large-scale environment, so this may be a rather basic question.
My apologies if that's the case.  I'm willing to RTFM, I just need to find
the right manual to read.

I'm wondering if it's possible to add a filter to cups to automatically
un-gzip an IPP print job that comes in with compression=gzip, *before*
it's written as a data file to /var/spool/cups?

If you've seen my other recent posts to the list, you know that we've
been having some trouble getting recent Macs (both Yosemite and Mavericks)
to submit jobs to our RHEL-based print server.

We've discovered that if we set up the queue on the Mac client as e.g.

 	ipp://printserver.fqdn/printers/printqueue?compression=none

then we can force the client to send the job without compression.  That's
a good workaround, but ideally we would want our RHEL6 cups 1.4.2 software
to detect that a submitted print job is compressed and automatically
decompress the data file(s) before they even get written to
/var/spool/cups.  I'm not talking about decompressing the job when it's
eventually released to a printer, I'm talking about decompressing it upon
acceptance.

Is that possible?  If so, does it involve additions to
mime.convs/mime.types, or some other mechanism?  Does anyone have an
example of how to do this?

Thanks much!

Tim
-- 
Tim Mooney                                             Tim.Mooney at ndsu.edu
Enterprise Computing & Infrastructure                  701-231-1076 (Voice)
Room 242-J6, Quentin Burdick Building                  701-231-8541 (Fax)
North Dakota State University, Fargo, ND 58105-5164