On 27/08/13 11:50, Andrew Wilkins wrote: > On Tue, Aug 27, 2013 at 8:44 AM, Tim Penhey <tim.pen...@canonical.com > <mailto:tim.pen...@canonical.com>> wrote: > > Perhaps we should have a sanity-check type callback into the provider > with the constraints at the time we want to add a machine. This would > give the null provider the early fail mechanism, and could also allow > other providers to error if people as asking for constraints that really > don't make sense. > > > I'm sort of thinking out aloud here: maybe this could used for checking > environment-specific constraints too? Some kind of > "VerifyMachineConstraints" method that will ensure your add-machine/--to > constraints are valid for the current provider/environment. In this case > constraints may be nil, but the null provider would just always return > false.
This is exactly what I'm thinking as well, but I had forgotten about the provider specific constraints. It does raise the question of what should happen if a provider specific constraint is passed to a provider that can't handle it. My suggestion is we fail. Tim -- Juju-dev mailing list Juju-dev@lists.ubuntu.com Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/juju-dev
