[Zope-CMF] modification date should not be bobobase_modification_time

[Rémi Houdaille]

Tres Seaver wrote :
> 
> If we call 'setModificationDate' in the skins (the PythonScripts which , then
> different sites can vary the policy by customizing. Perhaps calling it only
> in the skin methods which update the content (not the metadata, nor workflow)
> is the Right Thing (TM) for a default? To do anything more complicated, we
> would have to add policy, and UI for administering it, to the metadata tool.
> 

I agree with the need for a varying policy on this, and skins are the
simplest answer.

I however feel concerned about the fact that it allows for an
implementation
without any update of the modification_time attribute. This could be a
risk for
people who build new content types and/or skins: they *must* be aware of
the
modification_date management and they have to maintain its value up to
date.
This was the main advantage of bobobase_modification_time:
it is always transparently changed.

If we *do not* create modification_time attribute in
DefaultDublinCoreImpl
constructor, the previous behaviour (use of bobobase) is kept. This
ensures
existing content types not designed to manage the new attribute continue
to
work as before. Seems acceptable to me. This design decision must be
explicit,
otherwise somebody would be tempted to set the modification_date
initially.

Rémi