My take on it all is that, if we are to create a standard for IPP
notifications, then we should...
... explicitly define the specific IPP events that would cause a
notification to be generated. Various events have been
discussed, including job completion, job progress, printer
problems, and even more general object state transitions.
... explicitly define the information returned in the "machine-
readable" representation. Personally, I feel that the
most flexible, extensible, and useful means of doing
this is to say that "the object is the notification".
Specifically, if I subscribe for some sort of job
notification, then the "machine-readable" representation
for a resultant notification would be the actual job
object itself (presumably in the same application/ipp
representation that would be returned as the result of
a GetJobAttributes request). The amount of information
returned could be further limited by allowing the
requested attributes to be specified (as in GetJobAttr's).
... be very vague about the information returned in the "human-
readable" representation. I feel that it is appropriate
to say that a "human-readable" represenation MAY be
requested or returned (while the "machine-readable" MUST
be returned), and to say that, if returned, that "human-
readable" representation would be part of a multipart
MIME encoding, and to even possibly go as far as to say
something about character sets and encodings. But I
think that it is going too far to standardize the specific
"human-readable" text for each event.
one man's opinion...
...walker
-- Jim Walker <walker@dazel.com> System Architect/DAZEL Wizard DAZEL Corporation, Austin, TX