> 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. 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. > > > IIRC this has been discussed in the past and the justifications for > > including it in the template (as opposed to allowing metadata to be > > attached in the ReST API, as other projects already do for many things) > > were not compelling. > > I see that Keith Bray mentioned https://wiki.openstack.org/wiki/ > Heat/StackMetadata and https://wiki.openstack.org/wiki/Heat/UI in > another reply on this thread. Are there additional places to look > to find that discussion? > > I have also heard that there has been discussion of language > extension issues. Is that a separate discussion and, if so, where > can I read it? > > Thanks, > Mike > _______________________________________________ > OpenStack-dev mailing list > OpenStack-dev@lists.openstack.org > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev _______________________________________________ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
