[ZODB-Dev] Problem with handling of data managers that join transactions after savepoints

[Wichert Akkerman]

On 5/11/10 19:41 , Chris Withers wrote:
> Jim Fulton wrote:
>>>> I plan to implement A soon if there are no objections.
>>>>
>>>> Unless someone somehow convinced me to do D, I'll also add an
>>>> assertion in the Transaction.join method to raise an error if a
>>>> data manager joins more than once.
>>> Option A sounds sensible. It also means I won't have to change
>>> anything in the zope.sqlalchemy data manager.
>>
>> Very cool. I was hoping non-ZODB-data-manager authors
>> were paying attention. :)
>>
>> If anyone knows of any other, I would appreciate someone forwarding
>> this thread to them.
>
> zope.sendmail and MaildropHost have data managers.
> I've seen some file-based things that was a data manager and a few
> others in people's BFG stacks, maybe they can pipe up and/or let the
> others of those wsgi components know.

I wrote repoze.filesafe a while ago to do transaction-aware creation of 
files, which uses a datamanager. It never tries to join a transaction 
more than once, so should be fine.

Wichert.