[Zope-dev] Observer / Notification Interface Proposal

Michel Pelletier michel@digicool.com
Thu, 25 May 2000 11:09:23 -0700


Tres Seaver wrote:
> 
> Michel Pelletier <michel@digicool.com> wrote:
> >
> > http://www.zope.org/Members/michel/Projects/Interfaces/Discovery
> >
> > Thoughts on how they relate?  Are they the same thing?
> 
> I think this pattern is orthagonal to the ObserverAndNotification
> pattern, but is crucial to making things like
> TheClassFormerlyKnownAsCatalogAware and Ken's new WikiRelationship
> object work.  CORBA solves this by mandating that the ORB provide a
> lookup method::
> 
>    def resolve_initial_references( resource_type ):
> 
> where resource_type is a well-known string like 'NamingService', etc.
> 
> In our case, perhaps it needs to be::
> 
>    def findNearestResource( meta_type ):

There allready exists such a thing, superValues([meta_type]).  But I
think this is too weak to use as a discovery protocol.  An observable
may not know or care what type of observer it wants to discover.  Also,
when it finds a number of various resources, catalogs lets say, does it
just notify them all?  Is there a concept of a default?  Can they
negotiate?
 
-- 

-Michel Pelletier

http://www.zope.org/Members/michel/MyWiki

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