[Zope] A persistent problem -- monkey patch related?

[Dennis Allison]

Thanks for your comments Chris.  The '_p_oid' problem seems to be a
different, but possibly related problem to the persistence problem.  With
Jeremy's help I have modified the error logging portion of my Zope to help
identify the problem.  Current thinking is that it is a bug in Zope, but
we need more information.

The persistence problem manifests itself by disappearing data (sometimes).
My patch changes the data structure used for acl_users.  And, yeah, it
woulda been better to strt afresh, but that would mean ripping out a lot
of code which sorta grew and the associated debug problem.  So a patch
is a better choice until it's time to rewrite the whole thing.

I am very skeptical about monkey patched methods in Zope behaving the
right way vis a vis persistence.  When I next take things down, I will 
replace UserFolder with my own version which should resolve the issue, but
I am stil curious about what works and what doesn't with respect to
persistence.


On Fri, 23 Jan 2004, Chris Withers wrote:

> Dennis Allison wrote:
> 
> > I asked this question to the list a while back, but the responses I got
> > were a bit off-point.  Sad to say, the issue remains unresolved.
> > 
> > I have made some extensive mods to UserFolder and installed them with a
> > monkey patch.
> 
> Why not just subclass and have your own type of UserFolder?
> SimpleUserFolder makes this pretty easy ;-)
> 
> > I chose this approach because it looked to have the least impact on the
> > existing system, but now I am not so sure.  I've been getting _p_oid 
> > errors when the OODB is backing out of a transaction.  
> 
> Any chance of seeing what those errors are?
> 
> > that it's a Zope bug, but I am not so sure.  I suspect that something I
> > have done in the monkeypatch has triggered the problem.  My patch code
> > uses PersistentMapping() and expects that the system does the right thing
> > with respect to persistence in the new methods even though they are
> > patched in.
> 
> Hmmm, I wonder where in the transaction setup that PersistentMapping is getting 
> twiddled with?
> 
> > Can anyone shed light on the issue:  Is persistence inherited by monkey
> > patched methods?
> 
> Nope, wouldn't have thought so. Can you state your problem, there might be a 
> better way than your current solution which could rule it out as the source of 
> these problems...
> 
> cheers,
> 
> Chris
>