[Zope3-dev] Associations

[Janko Hauser]

Casey Duncan writes:
 > 
 > > Requiring objects that need relations to only be stored in an isolated data
 > > store is acceptable if you move away from a standard Zope structure, but if
 > > you want, for instance, CMF members to be able to add objects that can
 > > relate and be related to, while remaining in their folders for security and
 > > organization reasons, the solution is untenable.
 > 
 > Let me give you one of my own use cases:
 > 
 > I have a library application where I want all documents (which are subclassed 
 > Zope file objs) to share a single property schema. Currently this is 
 > accomplished by putting all of these documents into a special "DocumentStore" 
 > folder which allows them to acquire the schema.
 > 
 > I wish to use a decentralized document storage model in the next version. 
 > This will allow documents in the library to be scattered around anywhere in 
 > the hierarchy, which is advantageous for management purposes and allows it to 
 > play well with the CMF. So, I have to come up with some way for the documents 
 > to find their schema regardless of where they might be.
 > 

If these schemas are unique, or can be made so, wouldn't it be
possible to use a zcatalog to find the schema? I also find in some
bigger projects, that the structure of a site, imposed by navigation
and customers management demand works against the structure one would
choose from the programming point of view. If one can neglect
acquisition for the schema (meaning different parts of a schema can be
overwritten by the acquisition mechanismen a central registry, like a
zcatalog can be used. This would also work for 'moving' objects, if
they implement the right methods.

I often think, the zcatalog should play the role of an object
requester and query language.

I need to say, that I have not yet implemented such a pattern with the
zcatalog, so I can be totally off base.

__Janko