Excerpts from Zane Bitter's message of 2014-07-07 14:25:50 -0700: > With the Icehouse release we announced that there would be no further > backwards-incompatible changes to HOT without a revision bump. However, > I notice that we've already made an upward-incompatible change in Juno: > > https://review.openstack.org/#/c/102718/ > > So a user will be able to create a valid template for a Juno (or later) > version of Heat with the version > > heat_template_version: 2013-05-23 > > but the same template may break on an Icehouse installation of Heat with > the "stable" HOT parser. IMO this is almost equally as bad as breaking > backwards compatibility, since a user moving between clouds will > generally have no idea whether they are going forward or backward in > version terms.
Sounds like a bug in Juno that we need to fix. I agree, this is a new template version. > > (Note: AWS don't use the version field this way, because there is only > one AWS and therefore in theory they don't have this problem. This > implies that we might need a more sophisticated versioning system.) > A good manual with a "this was introduced in version X" and "this was changed in version Y" would, IMO be enough, to help users not go crazy and help us know whether something is a bug or not. We can probably achieve this entirely in the in-code template guide. > I'd like to propose a policy that we bump the revision of HOT whenever > we make a change from the previous stable version, and that we declare > the new version stable at the end of each release cycle. Maybe we can > post-date it to indicate the policy more clearly. (I'd also like to > propose that the Juno version drops cfn-style function support.) Agreed. I'm also curious if we're going to reject a template with version 2013-05-23 that includes list_join. If we don't reject it, we probably need to look at how to show the user warnings about version/feature skew. _______________________________________________ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev