On Tue, 2012-01-03 at 19:54 +0000, Ewan Mellor wrote: > I'd love to see openstack-common get off the ground, so I'm all in > favor of this. > > One question: why do you feel that you need such strong backwards > compatibility? If someone makes a change in openstack-common and > makes simultaneous changes in all OpenStack projects to match, isn’t > that sufficient?
No "simultaneous" change is ever actually simultaneous. We see this all the time with interop between keystone (in particular), nova, and glance. Once openstack-common gets into the picture, the interop problems stand to be significantly worse; if one tiny change is not backwards compatible, you break *everything* that uses openstack-common. The good thing, of course, is that it'll be noticed quickly; the bad thing is that all work gets significantly impeded until the fix(es) go in. Speaking from experience: it is possible to preserve N+2 backwards compatibility while still making major enhancements. It can be a pain in the butt sometimes, but it is doable, and, in cases like openstack-common, I think it is necessary. -- Kevin L. Mitchell <kevin.mitch...@rackspace.com> _______________________________________________ Mailing list: https://launchpad.net/~openstack Post to : openstack@lists.launchpad.net Unsubscribe : https://launchpad.net/~openstack More help : https://help.launchpad.net/ListHelp