[Zope3-dev] Re: Object Hub does not receive important events

[Jim Fulton]

Stephan Richter wrote:
> Hi Gary,
> 
> I was just trying to test the text index by having it filled using the 
> ObjectHub and a Registration subscriber. After I figured out that the service 
> name "EventSubscription" changed to "Subscription" (see checkins), I got the 
> Registration subscriber to work and was able to add new objects to the hub 
> and therefore to the index. 
> 
> Then however, I tried to modify and delete objects, but the 
> ObjectModifiedEvent and ObjectRemovedEvent are not being forwarded to the 
> Object Hub, so nothing happens.
> 
> As far as I can tell, there are two possible ways of fixing this:
> 
>   1. Subscribe the object hub directly to the two events.
> 
>   2. Have the Registration subscriber handle the two events.
> 
> If I visualize the design correctly in my head, I think option 2 would be the 
> correct one, since it seems to me that the "Registration subscriber" is 
> responsible for automatically managing the hub based on events.

I don't think that that's correct. I'm 99% sure that the hub is supposed
to be subscribed to modification and removal events.

See zope/app/interfaces/services/hub.py.

Ah, and see zope/app/services/hubcollaborations.txt.

Clearly, the hub is supposed to handler adds and removes.

There seems to be a special case for objects moved into or out
of the hubs place, but, frankly, copying and moving are a mess right
now and I would ignore them for this discussion.

I'm puzzed that the hub isn't registered for modified and removed
events. I guess this is partly the result that we aren't using it. :(

Jim

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