Re: [ZODB-Dev] Problem with handling of data managers that join transactions after savepoints
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. ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] Problem with handling of data managers that join transactions after savepoints
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'm also likely about to write one, but I'm dumb, so can't comment meaningfully on the options ;-) Chris -- Simplistix - Content Management, Batch Processing & Python Consulting - http://www.simplistix.co.uk ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] Problem with handling of data managers that join transactions after savepoints
On Mon, May 10, 2010 at 5:22 PM, Laurence Rowe wrote: > On 10 May 2010 21:41, Jim Fulton wrote: >> A. Change transaction._transaction.AbortSavepoint to remove the >> datamanager from the transactions resources (joined data managers) >> when the savepoint is rolled back and abort called on the data >> manager. Then, if the data manager rejoins, it will have joined >> only once. >> >> Update the documentation of the data manager abort method (in >> IDataManager) to say that abort is called either when a transaction >> is aborted or when rolling back to a savepoint created before the >> data manager joined, and that the data manager is no longer joined >> to the transaction after abort is called. >> >> This is a backward incompatible change to the interface (because it >> weakens a precondition) that is unlikely to cause harm. > >> 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. Jim -- Jim Fulton ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] Problem with handling of data managers that join transactions after savepoints
On 10 May 2010 21:41, Jim Fulton wrote: > A. Change transaction._transaction.AbortSavepoint to remove the > datamanager from the transactions resources (joined data managers) > when the savepoint is rolled back and abort called on the data > manager. Then, if the data manager rejoins, it will have joined > only once. > > Update the documentation of the data manager abort method (in > IDataManager) to say that abort is called either when a transaction > is aborted or when rolling back to a savepoint created before the > data manager joined, and that the data manager is no longer joined > to the transaction after abort is called. > > This is a backward incompatible change to the interface (because it > weakens a precondition) that is unlikely to cause harm. > 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. Laurence ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org https://mail.zope.org/mailman/listinfo/zodb-dev
