[ZODB-Dev] Fixing POSKeyErrors :-)

[Jim Fulton]

On Feb 14, 2008, at 10:29 AM, Binger David wrote:

>
> On Feb 14, 2008, at 9:43 AM, Jim Fulton wrote:
>
>>> On the other hand, it seems
>>> clear that cross-storage references make the system as a whole
>>> (software + people) less reliable.
>>
>> I don't agree in general.
>
> Uh.  I thought we were talking about reported POSKeyErrors that  
> would not exist
> if there were no such thing as cross-storage references.  I don't  
> understand
> what there is to disagree with here.  Are you saying that cross- 
> storage
> references reduce the risk of other application-breaking conditions?

We, ZC, are using cross-database references quite productively in a  
number of applications.


>
>
>>
>>> Perhaps I misunderstand, but low-level cross-site references seem  
>>> like "secret"
>>> weakrefs.  Maybe we'd be better off if they were explicit, higher- 
>>> level objects,
>>> used and dereferenced intentionally where required.
>>
>>
>> I don't object to this approach. I'll note that we had an approach  
>> like this before for Zope (mounts) and it had plenty of  
>> disadvantages of it's own, including injecting Zope-specific code  
>> into ZODB.
>>
>> If someone can make something like this work without modifying  
>> ZODB, I won't object.
>
> Right.  There is no reason for this approach to involve ZODB at all.
> If broken "references" must be tolerated, I'm suggesting that they  
> should be dealt
> with in application/Zope-level code, not in ZODB.

I think you are being naive.  This isn't a new application. Perhaps  
you should study the old Zope 2 mounting code.

In any case, I'm not going to argue the point any further.

Jim

--
Jim Fulton
Zope Corporation