Awesome! I only have one follow-up question: Regarding #6 & #7, how will the clone behavior work given that the defaults are hydrated by a non-versioned jinja template?
Scenario Timeline: T1) Cloud provider begins with the default jinja template, but changes the values for properties 'a' and 'b'. (Template Version #1) T2) User X deploys a database instance T3) Cloud provider decides to update the existing template by modifying property 'c'. (Template Version #2) T4) User Z deploys a database instance I think it goes without saying that User Z's instance gets Template Version #2 (w/ changes to a & b & c), but does User X? If it's a "true" clone, User X should be isolated from a change in defaults, no? Come to think about it, this is eerily similar to security-groups: administratively, it can be beneficial to share a configuration/security-group across multiple instances, but it can also be a nightmare. Internally, it's extremely rare that we wish to apply a database change to multiple tenants at once, so I'd argue at a minimum to support a CONF opt-in for isolation, if not default to it. On a related note: Will the default template for a service-type be represented as a default configuration-group? If so, I imagine it can be managed through the API (or MGMT API)? From: Craig Vyvial <cp16...@gmail.com> Reply-To: OpenStack Development Mailing List <openstack-dev@lists.openstack.org> Date: Wednesday, October 2, 2013 10:06 AM To: OpenStack Development Mailing List <openstack-dev@lists.openstack.org> Subject: Re: [openstack-dev] [trove] Configuration API BP I'm glad we both agree on most of these answers. :) On Oct 2, 2013 11:57 AM, "Michael Basnight" <mbasni...@gmail.com> wrote: On Oct 1, 2013, at 11:20 PM, McReynolds, Auston wrote: > I have a few questions left unanswered by the blueprint/wiki: > > #1 - Should the true default configuration-group for a service-type be > customizable by the cloud provider? Yes > > #2 - Should a user be able to enumerate the entire actualized/realized > set of values for a configuration-group, or just the overrides? actualized > > #3 - Should a user be able to apply a different configuration-group on > a master, than say, a slave? Yes > > #4 - If a user creates a new configuration-group with values equal to > that of the default configuration-group, what is the expected > behavior? Im not sure thats an issue. You will select your config group, and it will be the one used. I believe you are talking the difference between the "template" thats used to set up values for the instance, and the config options that users are allowed to edit. Those are going to be "appended", so to speak, to the existing template. Itll be up to the server software to define what order values, if duplicated, are read / used. > > #5 - For GET /configuration/parameters, where is the list of supported > parameters and their metadata sourced from? i believe its a db tableŠ someone may have to correct me there. > > #6 - Should a user be able to reset a configuration-group to the > current default configuration-group? Yes, assuming we have a "default config group", and im not sure we have a concept of that. We have what the install creates, the templated config file. Removing the association of your config from the instance will do this thought. > > #7 - Is a new configuration-group a clone of the then current default > configuration-group with various changes, or will inheritence be > utilized? I think clone will be saner for now. But you can edit your group with a PATCH, and that will not clone it. See [1] first paragraph. > > #8 - How should the state of pending configuration-group changes be > reflected in GET /instances/:id ? How will this state be > persisted? You are talking about changes that require a restart i believe. I think this falls into the same category as our conversation about minor version updates. We can have a pretty generic "restart required" somewhere there. > > #9 - Reminder: Once multiple service-types and versions are supported, > the configuration-group will need a service-type field. Most def. You will only be able to assign relevant configs to their service-types, and the /configuration/parameters will need to be typed too. > > #10 - Should dynamic values (via functions and operators) in > configuration-groups be supported? > Example: innodb_buffer_pool_size = 150 * flavor['ram']/512 Hmmmm. This is quite interesting. But no, not v1. I totally agree w/ the nice-to-have. Good idea though, we should add it to the blueprint. > > My Thoughts: > > #1 - Yes > #2 - Actualized > #3 - Yes > #4 - Depends on whether the approach for configuration-groups is to > clone or to inherit. > #5 - ? > #6 - Yes > #7 - ? > #8 - ? > #9 - N/A > #10 - In the first iteration of this feature I don't think it's an > absolute necessity, but it's definitely a nice-to-have. The > design/implementation should not preclude this from being easily > added in the future. > > Where "?" == "I'd like to think about it a bit more, but I have a gut > feeling" > > Thoughts? [1] http://lists.openstack.org/pipermail/openstack-dev/2013-October/015919.html <http://lists.openstack.org/pipermail/openstack-dev/2013-October/015919.ht ml> _______________________________________________ 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