Our reference transformer analyses and our destroy transformer analyses
are built around static (not-yet-expanded) addresses so that they can
correctly handle mixtures of expanded and not-yet-expanded objects in the
same graph.
However, this characteristic also makes them unnecessarily conservative
in their handling of references between resources within different
instances of the same module: we know they can never interact with each
other in practice because the dependencies for all instances of a module
are the same and so one instance cannot possibly depend on another.
As a compromise then, here we introduce a new helper function that can
recognize when a proposed edge is between two resource instances that
belong to different instances of the same module, and thus allow us to
skip actually creating those edges even though our imprecise analyses
believe them to be needed.
As well as significantly reducing the number of edges in situations where
multi-instance resources appear inside multi-instance modules, this also
fixes some potential cycles in situations where a single plan includes
both destroying an instance of a module and creating a new instance of the
same module: the dependencies between the objects in the instance being
destroyed and the objects in the instance being created can, if allowed
to connect, cause Terraform to believe that the create and the destroy
both depend on one another even though there is no need for that to be
true in practice.
This involves a very specialized helper function to encode the situation
where this exception applies. This function has an ugly name to reflect
how specialized it is; it's not intended to be of any use outside of these
three situations in particular.
GraphNodeModulePath is similar to GraphNodeSubPath, except that it
returns an addrs.Module rather than an addrs.ModuleInstance. This is
used by the ReferenceTransformer to connect references, when modules may
not yet be expanded.
Because references only exist within the scope of a module, we can
connect everything knowing only the module path. If the reference is to
an expanded module instance output, we can still properly order the
reference because we'll wait for the entire module to complete
evaluation.
* WIP: dynamic expand
* WIP: add variable and local support
* WIP: outputs
* WIP: Add referencer
* String representation, fixing tests it impacts
* Fixes TestContext2Apply_outputOrphanModule
* Fix TestContext2Apply_plannedDestroyInterpolatedCount
* Update DestroyOutputTransformer and associated types to reflect PlannableOutputs
* Remove comment about locals
* Remove module count enablement
* Removes allowing count for modules, and reverts the test,
while adding a Skip()'d test that works when you re-enable
the config
* update TargetDownstream signature to match master
* remove unnecessary method
Co-authored-by: James Bardin <j.bardin@gmail.com>
The changes to our GraphNodeReferencable and GraphNodeReferencer
interfaces were not also reflected in our testing structs here, and so
these tests were no longer working.
This updates these implementations to the new required signatures,
adapting the simplified model used in the structs to generate local
variable references, since the reference model no longer uses the
arbitrary strings that this test originally depended on.
We also remove some of the tests here since the functionality they were
testing no longer applies: inter-module dependencies are now handled by
the graph nodes producing extra ReferencableAddrs, and the "backup" form
is no longer used because our new address model is able to distinguish
resources from resource instances without the need for the magical
backup reference forms we previously used.
After the refactoring to integrate HCL2 many of the tests were no longer
using correct types, attribute names, etc.
This is a bulk update of all of the tests to make them compile again, with
minimal changes otherwise. Although the tests now compile, many of them
do not yet pass. The tests will be gradually repaired in subsequent
commits, as we continue to complete the refactoring and retrofit work.
terraform: more specific resource references
terraform: outputs need to know about the new reference format
terraform: resources w/o a config still have a referencable name
