[Zope3-dev] ObjectHub notes: removing objects

[Jim Fulton]

Steve Alexander wrote:
> Hi Kevin, Gary,
> 
> Nice answer Gary. I'd like to make a few comments though

....

>> this part of the mechanism has two proposed solutions, so far.  There is
>> the "don't do anything without getting an event-sending adapter around
>> it first" approach, which would solve your concern because it would not
>> be the folder that sent the events. This or some variation will probably
>> happen since it is what I heard last from Jim, I think. 
>> This might be annoying and fragile if the programmer had to get the
>> adapter every time IMHO.  Maybe this solution could move towards the
>> idea of this kind of wrapper being part of the traversal mechanism,
>> which might just be the best thing--I haven't thought that through, and
>> I haven't heard anyone actually propose it, and it probably is a bit
>> frightening :-).  
> 
> 
> Hey, that's a cool idea! I have no idea how it would play out, but it 
> deserves some thought :)

Let's wait until we have mopre experience with adapters before we
contemplate this.


> 
>> The other approach (which I have on occasion espoused) says that folders
>> might need to send some of the pertinent events themselves about their
>> contents.  If this were the case, we would simply need to raise errors
>> whenever someone tried to do something such as what you describe (i.e.,
>> the object hub might say to a registered object that tried to move into
>> a non-event-sending folder, "sorry, you can't move *there* because I
>> can't hear you!")
> 
> 
> Too Zope2-mixin-classy for my tastes ;)

Agreed.

....

> Jim Fulton has also mentioned an EventChannel that saves up events, and 
> sends them out batched up every minute or so. This can have some very 
> good effects on the resources used then cataloguing changing content.

If you'd like to see a first cut at this, see the QueuedCatalog product
for Zope 3 (in CVS under Products/QueuedCatalog).

Jim

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