[ZODB-Dev] Ordering before commit hooks
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi, I would like to order the before commit hooks on a transaction by being able to specify an order for a subscriber at registration time. For the moment, they are called in the order they've been registred. The order argument could be an integer with a default value to 0 added to the registration method. We could just insert the subscriber wihin the queue according to this order parameter if found *or* sorting the queue according to this parameter before flushing the queue and calling the hooks. What do you think ? J. - -- Julien Anguenot | Nuxeo RD (Paris, France) CPS Platform : http://www.cps-project.org Zope3 / ECM : http://www.z3lab.org mail: anguenot at nuxeo.com; tel: +33 (0) 6 72 57 57 66 -BEGIN PGP SIGNATURE- Version: GnuPG v1.4.1 (GNU/Linux) Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org iD8DBQFC8z2CGhoG8MxZ/pIRAu8sAJ4vHRVCMcNNQoRUVZaxQ6risIdzlgCcDhAl EVYn/Ew0jXfhUn+d4WMdvhk= =dkcf -END PGP SIGNATURE- ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] Ordering before commit hooks
On Aug 5, 2005, at 6:20 AM, Julien Anguenot wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi, I would like to order the before commit hooks on a transaction by being able to specify an order for a subscriber at registration time. For the moment, they are called in the order they've been registred. I like this idea, and was just idly wishing for it this morning. The order argument could be an integer with a default value to 0 added to the registration method. I usually like the word 'priority' for this sort of value, rather than 'order'. To me 'order' implies unique value--i.e., with 'order' I am mildly surprised to learn that two entries may have the same order. I am not surprised that two entries may share a priority. If negative values are acceptable then a default value of 0 is OK by me. We could just insert the subscriber wihin the queue according to this order parameter if found *or* sorting the queue according to this parameter before flushing the queue and calling the hooks. I think it would be ideal if before commit hooks with the same priority continue to be in the order in which they were added. There are a number of ways to accomplish this and I expect you can choose a very reasonable one :-) Gary ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
Re: [ZODB-Dev] Ordering before commit hooks
On Aug 5, 2005, at 2:33 PM, Tim Peters wrote: [Julien Anguenot] ... The order argument could be an integer with a default value to 0 added to the registration method. [Gary Poster] I usually like the word 'priority' for this sort of value, rather than 'order'. To me 'order' implies unique value--i.e., with 'order' I am mildly surprised to learn that two entries may have the same order. I am not surprised that two entries may share a priority. It's wholly unclear to me, given a callback with associated value 0 and another with associated value 999, which one is supposed to be invoked first. If the parameter is called priority, then I'd expect 999 to win; if it's called order, then 0. To each his own, I suppose--'first priority' and 'last priority' is my model, in which, at the least, a priority of 1 would be first priority and a priority of 999 is a reasonable last priority (acknowledging a positive infinity as something that would take the honor of being reliably last priority, then). A priority of 0, and a negative priority, start to muddle the model a bit, certainly. But anyway, if you don't see 'priority' in that way, then yes, it is perhaps unclear in a different dimension than 'order' is unclear. :-) Gary ___ For more information about ZODB, see the ZODB Wiki: http://www.zope.org/Wikis/ZODB/ ZODB-Dev mailing list - ZODB-Dev@zope.org http://mail.zope.org/mailman/listinfo/zodb-dev
