Subject: Re: IPP> MOD - Proposal to remove ValidateJob in IPP 1.0

From: [email-masked]
Date: Mon, 14 Jul 1997 11:15:26 PST

> From: Keith Carter <[email-masked]>
> Date: Fri, 11 Jul 1997 18:06:16 -0400
> 
> In the spirit of simplification, I propose we remove VaildateJob from IPP 1.0
> because (1) GetAttributes is now a mandatory operation on a Printer (2) an
> application can use GetAttributes to obtain valid attributes and values for a
> Printer BEFORE submitting a job to the Printer (3) removing ValidateJob is one
> less operation to implement and test i.e. we remove a straw from the IPP
> camel's back (as someone stated in the email, these straws do add up).

(I haven't been following all the details of the ValidateJob discussion,
so if these comments are off-track, someone please nudge things back in
line.) 

I thought one of the things missing from GetAttributes was the ability
to check for constraints that might make a particular COMBINATION of
attributes impossible for the printer to implement.  The key issue here
is that, just because a printer some set of data types, media types,
some set of finishing options, etc., doesn't mean all the combinations
are supported.  ("Sorry, I can't print duplex on card stock or A3.") 
Real-world devices don't have nice orthogonal feature sets. 

So, I thought the idea was that you could use ValidateJob job to check
for problems before shipping off all the document data.  

::  David Kellerman         Northlake Software      503-228-3383
::  [email-masked] Portland, Oregon        fax 503-228-5662