looks like a zope.transaction issue to me, or at least one where they'd have to show me how they need to use the Session. They seem to be calling upon session.transaction.prepare() directly at a time when that session.transaction is no longer associated with the parent session. You'd need to take it up with the zope.transaction folks first.
On Jun 25, 2013, at 5:49 AM, Pau Tallada <[email protected]> wrote: > Hi! > > I think I've stepped on the same or similar bug. > > I have a software which uses zodb transactions to synchronize operations in > two databases. In the end, the two databases are the same (we are using the > exact same postgresql connection url for both). The software runs fine if > only one instance is launched. > > But... if I launch more than one instance at a time, there is a great > possibility that I get an Exception like this: > > Traceback (most recent call last): > File > "/nfs/pau/PAUdm/codes/tonello/ENV/packaging_test/lib/python2.6/site-packages/brownthrower/dispatcher/static/__init__.py", > line 238, in _run_job > transaction.commit() > File > "/nfs/pau/PAUdm/codes/tonello/ENV/packaging_test/lib/python2.6/site-packages/transaction/_manager.py", > line 111, in commit > return self.get().commit() > File > "/nfs/pau/PAUdm/codes/tonello/ENV/packaging_test/lib/python2.6/site-packages/transaction/_transaction.py", > line 280, in commit > reraise(t, v, tb) > File > "/nfs/pau/PAUdm/codes/tonello/ENV/packaging_test/lib/python2.6/site-packages/transaction/_transaction.py", > line 271, in commit > self._commitResources() > File > "/nfs/pau/PAUdm/codes/tonello/ENV/packaging_test/lib/python2.6/site-packages/transaction/_transaction.py", > line 417, in _commitResources > reraise(t, v, tb) > File > "/nfs/pau/PAUdm/codes/tonello/ENV/packaging_test/lib/python2.6/site-packages/transaction/_transaction.py", > line 394, in _commitResources > rm.tpc_vote(self) > File > "/nfs/pau/PAUdm/codes/tonello/ENV/packaging_test/lib/python2.6/site-packages/zope/sqlalchemy/datamanager.py", > line 153, in tpc_vote > self.tx.prepare() > File > "/nfs/pau/PAUdm/codes/tonello/ENV/packaging_test/lib/python2.6/site-packages/sqlalchemy/orm/session.py", > line 313, in prepare > if self._parent is not None or not self.session.twophase: > AttributeError: 'NoneType' object has no attribute 'twophase' > > I'm completely lost on this :( > > Any clues? > > BTW, sessions are created like this: > > engine = create_engine('postgresql://foo') > > session_maker = scoped_session(sessionmaker( > bind = engine, > twophase = True, > extension = ZopeTransactionExtension() > )) > > Thank you very much in advance :) > > Pau. > > 2013/2/20 Michael Bayer <[email protected]> > you'd have to illustrate a working example of the code that causes that. > > > On Feb 20, 2013, at 6:18 AM, Christian Démolis <[email protected]> > wrote: > >> Hi, >> >> AttributeError: 'NoneType' object has no attribute 'twophase' >> >> >> 243. >> 244. >> 245. >> 246. >> 247. >> 248. >> >> 249. >> 250. >> 251. >> 252. >> >> "Session already has a Connection associated for the >> " >> "given Connection's Engine") >> >> >> >> else: >> conn = bind.contextual_connect() >> >> >> >> >> if self.session.twophase and self._parent is None: >> >> >> >> >> transaction = conn.begin_twophase() >> elif self.nested: >> >> >> >> transaction = conn.begin_nested() >> else: >> >> Anybody understand this error ? >> >> -- >> You received this message because you are subscribed to the Google Groups >> "sqlalchemy" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> To post to this group, send email to [email protected]. >> Visit this group at http://groups.google.com/group/sqlalchemy?hl=en. >> For more options, visit https://groups.google.com/groups/opt_out. >> >> > > > -- > You received this message because you are subscribed to the Google Groups > "sqlalchemy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/sqlalchemy?hl=en. > For more options, visit https://groups.google.com/groups/opt_out. > > > > > > -- > ---------------------------------- > Pau Tallada Crespí > Dep. d'Astrofísica i Cosmologia > Port d'Informació Científica (PIC) > Tel: +34 93 586 8233 > ---------------------------------- > > > -- > You received this message because you are subscribed to the Google Groups > "sqlalchemy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/sqlalchemy. > For more options, visit https://groups.google.com/groups/opt_out. > > -- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/sqlalchemy. For more options, visit https://groups.google.com/groups/opt_out.
