instances.Set is only used after all instances have been processes, so
it should therefor only handle known instances and not panic when given
an address that traverses an unexpanded module.
Previously we were treating it as a programming error to ask for the
instances of a resource inside an instance of a module that is declared
but whose declaration doesn't include the given instance key.
However, that's actually a valid situation which can arise if, for
example, the user has changed the repetition/expansion mode for an
existing module call and so now all of the resource instances addresses it
previously contained are "orphaned".
To represent that, we'll instead say that an invalid instance key of a
declared module behaves as if it contains no resource instances at all,
regardless of the configurations of any resources nested inside. This
then gives the result needed to successfully detect all of the former
resource instances as "orphaned" and plan to destroy them.
However, this then introduces a new case for
NodePlannableResourceInstanceOrphan.deleteActionReason to deal with: the
resource configuration still exists (because configuration isn't aware of
individual module/resource instances) but the module instance does not.
This actually allows us to resolve, at least partially, a previous missing
piece of explaining to the user why the resource instances are planned
for deletion in that case, finally allowing us to be explicit to the user
that it's because of the module instance being removed, which
internally we call plans.ResourceInstanceDeleteBecauseNoModule.
Co-authored-by: Alisdair McDiarmid <alisdair@users.noreply.github.com>
This is a first pass at implementing refactoring.ValidateMoves, covering
the main validation rules.
This is not yet complete. A couple situations not yet covered are
represented by commented test cases in TestValidateMoves, although that
isn't necessarily comprehensive. We'll do a further pass of filling this
out with any other subtleties before we ship this feature.
In order to precisely implement the validation rules for "moved"
statements we need to be able to test whether particular instances were
declared in the configuration.
The instance expander is the source of record for which instances we
decided while creating a plan, but it's API is far more involved than what
our validation rules need, so this new AllInstances method returns a
wrapper object with a more straightforward API that provides read-only
access to just the question of whether particular instances got registered
in the expander already.
This API covers all three of the kinds of objects that move statements can
refer to. It includes module calls and resources, even though they aren't
_themselves_ "instances" in the sense we usually mean, because the module
instance addresses they are contained within _are_ instances and so we
need to take their dynamic instance keys into account when answering these
queries.
This is part of a general effort to move all of Terraform's non-library
package surface under internal in order to reinforce that these are for
internal use within Terraform only.
If you were previously importing packages under this prefix into an
external codebase, you could pin to an earlier release tag as an interim
solution until you've make a plan to achieve the same functionality some
other way.
This is part of a general effort to move all of Terraform's non-library
package surface under internal in order to reinforce that these are for
internal use within Terraform only.
If you were previously importing packages under this prefix into an
external codebase, you could pin to an earlier release tag as an interim
solution until you've make a plan to achieve the same functionality some
other way.
