Excerpts from Thomas Spatzier's message of 2014-04-03 08:36:20 -0700: > > From: Mike Spreitzer <mspre...@us.ibm.com> > > To: "OpenStack Development Mailing List \(not for usage questions\)" > > <openstack-dev@lists.openstack.org> > > Date: 03/04/2014 07:10 > > Subject: Re: [openstack-dev] [heat] metadata for a HOT > > > > Zane Bitter <zbit...@redhat.com> wrote on 04/02/2014 05:36:43 PM: > > > > > I think that if you're going to propose a new feature, you should at > > > least give us a clue who you think is going to use it and what for ;) > > > > I was not eager to do that yet because I have not found a fully > > satisfactory answer yet, at this point I am exploring options. But > > the problem I am thinking about is how Heat might connect to a > > holistic scheduler (a scheduler that makes a joint decision about a > > bunch of resources of various types). Such a scheduler needs input > > describing the things to be scheduled and the policies to apply in > > scheduling; the first half of that sounds a lot like a Heat > > template, so my thoughts go in that direction. But the HOT language > > today (since https://review.openstack.org/#/c/83758/ was merged) > > does not have a place to put policy that is not specific to a > singleresource. > > I think you bring up a specific use case here, i.e. applying "policies" for > placement/scheduling when deploying a stack. This is just a thought, but I > wonder whether it would make more sense to then define a specific extension > to HOT instead of having a generic metadata section and stuffing everything > that does not fit into other places into metadata. >
Ever read about Larry "no modes" Tesler? Read up on his arguments against modes. I would much prefer any policies to be actual resources which the resources interact with, rather than template wide modes. > I mean, the use case Keith brought up are completely different (UI and user > related), and I understand both use cases. But is the idea to put just > everything into metadata, or would different classes of use cases justify > different section? The latter would enforce better documentation of > semantics. If everyhing goes into a metadata section, the contents also > need to be clearly specified. Otherwise, the resulting template won't be > portable. Ok, the standard HOT stuff will be portable, but not the > metadata, so no two users will be able to interpret it the same way. > We had a fairly long debate about keywords and meta-information in HOT and I thought we came to the conclusion that it belongs in the API and not in the template language. _______________________________________________ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev