[cups.general] STR #1923 fix incomplete?

[Michael Sweet]

Tim Waugh wrote:
> On Thu, 2007-02-15 at 12:41 -0500, Michael Sweet wrote:
>> I don't see us providing a way to distinguish between compiled-in
>> defaults and admin-set defaults.
> 
> Why not?  Do you think the user interface we're using should be
> different in some way?

 From a practical standpoint, there is no difference between defaults
that come from a compiled-in constant and defaults that are set by
the administrator in cupsd.conf or printers.conf/classes.conf.

>> However, the following -default
>> attributes are always set and cannot be removed:
> 
> I think you're now misunderstanding my use of 'removed'.  So let me be
> as clear as I can:
> 
> I just want to build a graphical interface for adding and removing
> 'Option' lines in printers.conf, and I want to implement it using IPP
> calls alone.

Not possible now, and (like I said) probably not possible in the
future because it is an implementation detail we don't want to
expose to applications.  We have RFEs for implementing LDAP-based
storage, for example, that would eliminate the .conf files entirely
(if you wanted to do that sort of thing... :)

> Currently the interface cannot be implemented without fetching and
> parsing printers.conf to find out what 'Option' lines there are.

.... which is an implementation detail that is subject to change at
any time...

>>      copies-default
> 
> So, obviously the attribute cannot be deleted in the IPP sense, but
> there can be an 'Option copies' line, set by the admin, that can be
> removed -- and this can be done using IPP calls.  It just isn't possible
> to ascertain using IPP calls whether there *is* an 'Option copies' line
> in the first place, since 'copies-default' is always present.

I would recommend against treating IPP as a way to edit the
printers.conf file.  That file (and classes.conf) is a data store
used by the scheduler to maintain queue configuration and state
information, and is re-written for every state and configuration
change.  If we decided to replace printers.conf with some other
mechanism (LDAP, SQLite DB, etc.) or change the format, anything
you do now will likely break.

All you can really show to the user are default options + values,
with "reset" next to the required ones and "delete" next to the
optional ones.  Whether there is an Option line in printers.conf
(or classes.conf) is a moot point.

-- 
______________________________________________________________________
Michael Sweet, Easy Software Products           mike at easysw dot com
Internet Printing and Document Software          http://www.easysw.com