On 02/29/2016 05:23 PM, Matt Riedemann wrote: > > > On 2/29/2016 2:54 PM, Sean Dague wrote: >> On 02/29/2016 11:59 AM, Sean Dague wrote: >>> The nova/hooks.py infrastructure has been with us since early Nova. It's >>> currently only annotated on a few locations - 'build_instance', >>> 'create_instance', 'delete_instance', and 'instance_network_info'. It's >>> got a couple of unit tests on it, but nothing that actually tests real >>> behavior of the hooks we have specified. >>> >>> It does get used in the wild, and we do break it with changes we didn't >>> ever anticipate would impact it - >>> https://bugs.launchpad.net/nova/+bug/1518321 >>> >>> However, when you look into how that is used, it's really really odd and >>> fragile - >>> https://github.com/richm/rdo-vm-factory/blob/master/rdo-ipa-nova/novahooks.py#L248 >>> >>> >>> >>> def pre(self, *args, **kwargs): >>> # args[7] is the injected_files parameter array >>> # the value is ('filename', 'base64 encoded contents') >>> ipaotp = str(uuid.uuid4()) >>> ipainject = ('/tmp/ipaotp', base64.b64encode(ipaotp)) >>> args[7].extend(self.inject_files) >>> args[7].append(ipainject) >>> >>> In our continued quest on being more explicit about plug points it feels >>> like we should other document the interface (which means creating >>> stability on the hook parameters) or we should deprecate this construct >>> as part of a bygone era. >>> >>> I lean on deprecation because it feels like a thing we don't really want >>> to support going forward, but I can go either way. >>> >>> -Sean >>> >>> P.S. I'm starting to look at in tree functional testing for all of this, >>> in the event that we decide not to deprecate it. It's definitely made a >>> little hard by the way all exceptions are caught when hooks go wrong. >> >> As there seemed to be some early enthusiasm for this from the core team, >> the deprecation patch is proposed here - >> https://review.openstack.org/#/c/286276/ >> >> Unless there is a big reversal of sentiment I'd suggest we get that >> landed in Mitaka so that this is signalled to people going forward, and >> we can collect use cases for things that are currently using hooks that >> we may want to support in other ways in Newton. >> >> -Sean >> > > I think you should probably also post this to the operators mailing list > before we actually deprecate hooks.
I'm not sure that's really true. As a team we have to decide we're going to deprecate or document this facility. The status quo is really not a thing. So unless we've got folks that believe we should crystalize this interface, and are signing up for doing that (which means you can't change build_instance internal function parameters ever), then I think it's fine to deprecate. We can measure our removal timeframe based on reaction to that. -Sean -- Sean Dague http://dague.net __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev