When an operation fails, providers may return a null new value rather than
returning a partial state. In that case, we'd prefer to keep the old value
so that we stand the best chance of being able to retry on a subsequent
run.
Previously we were making an exception for the delete action, allowing
the result of that to be null even when an error is returned. In practice
that was a bad idea because it would cause Terraform to lose track of the
object even though it might not actually have been deleted.
Now we'll retain the old object even in the delete case. Providers can
still return partial new objects if they were able to partially complete
a delete operation, in which case we'll discard what we had before, but
if the result is null with errors then we'll assume the delete failed
entirely and so just keep the old state as-is, giving us the opportunity
to refresh it on the next run to see if anything actually happened after
all.
(This also includes a new resource in the test provider which isn't used
by the patch but was useful for some manual UX testing here, so I thought
I'd include it in case it's similarly useful in future, given how simple
its implementation is.)
Due to the lossiness of our legacy models for diff and state, shimming a
diff and then creating a state from it produces a different result than
shimming a state directly. That means that ImportStateVerify no longer
works as expected if there are any Computed attributes in the schema where
d.Set isn't called during Read.
Fixing that for every case would require some risky changes to the shim
behavior, so we're instead going to ask provider developers to address it
by adding `d.Set` calls where needed, since that is the contract for
"Computed" anyway -- a default value should be produced during Create, and
thus by extension during Import.
However, since a common situation where this occurs is attributes marked
as "Removed", since all of the code that deals with them has generally
been deleted, we'll avoid problems in that case here by treating Removed
attributes as ignored for the purposes of ImportStateVerify.
This required exporting some functionality that was formerly unexported
in helper/schema, but it's a relatively harmless schema introspection
function so shouldn't be a big deal to export it.
This is not a recommended method, but it does serve to verify that the
set values in the ResourceData internal state are correctly computed,
which indicates that the expected configuration was passed in.
Add a diff test using a shcema with ConfigModeAttr.
It's in the test provider, because that is what is mostly responsible
for exercising diff.Apply, and where the other tests are.
These are the largest source of the old "diffs didn't match after apply"
errors. It's almost always an upstream dependency that caused the final
error.
For any block content we evaluate dynamically via this API, we'll make a
special allowance for users to optionally write members of a list
attribute instead as a sequence of nested blocks, thus allowing some
existing provider features that were assuming this capability to continue
to support it after v0.12.
This should not be used for any new provider features, and should ideally
be eventually phased out so that there aren't two
similar-but-slightly-different syntaxes for saying the same thing.
The previous commit added this flag but did not implement it. Here we
implement it by adjusting the shape of schema we return to Terraform Core
to mark the attribute as untyped and then ensure that gets handled
correctly on the SDK side.
The previous commit added a new flag to schema.Schema which is documented
to make a list with MaxItems: 1 be presented to Terraform Core as a single
value instead, giving a way to switch to non-list nested resources without
it being a breaking change for Terraform v0.11 users as long as it's done
prior to a provider's first v0.12-compatible release.
This is the implementation of that mechanism. It's intentionally
implemented as a suite of extra fixups rather than direct modifications to
existing shim code because we want to ensure that this has no effect
whatsoever on the result of a resource type that _isn't_ using AsSingle.
Although there is some small unit test coverage of the fixup steps here,
the primary testing for this is in the test provider since the integration
of all of these fixup steps in the correct order is the more important
result than any of the intermediate fixup steps.
This should be the final change from removing the flatmap normalization.
Since we're no longer trying to a consistent zero or null value in the
flatmap config, rather we're trying to maintain the previously applied
value, ReadResource also needs to apply the normalizeNullValues step in
order to prevent unexpected diffs.
This makes some slight adjustments to the shape of the schema we
present to Terraform Core without affecting how it is consumed by the
SDK and thus the provider. This mechanism is designed specifically to
avoid changing how the schema is interpreted by the SDK itself or by the
provider, so that prior behavior can be preserved in Terraform v0.11 mode.
This also includes a new rule that Computed-only (i.e. not also Optional)
schemas _always_ map to attributes, because that is a better mapping of
the intent: they are object values to be used in expressions. Nested
blocks conceptually represent nested objects that are in some sense
independent of what they are embedded in, and so they cannot themselves be
computed.
As we've improved the cty.Value normalization, we need to remove
normalization procedures from the flatmap handling. Keeping the empty
containers in the flatmap will prevent unexpected nils from being added
to some schema configurations
Providers were not strict (and were not forced to be) about customizing
the diff when a computed attribute needed to be updated during apply.
The fix we have in place to prevent loss of information during the
helper/schema apply process would add in single missing value back in.
The first place this was caught was when we attempt to fix up the
flatmapped attributes. The 1->0 count error is now better handled by our
cty.Value normalization step, so we can remove the special apply case
here altogether
The next place is in normalizeNullValues, and since the intent was to
re-insert missing zero-value lists and sets, adding a check for a length
of 0 protects us from adding in extra elements.
The new test fixture emulated common provider behavior of re-computing
values without customizing the diff. Since we can work around it, and
core will provider appropriate warnings, the shims should try to
maintain the legacy behavior.
The NewExtra values are stored outside the diff from plan, and the
original keys may not contain the ~ prefix. Adding the NewExtra back
into the diff with the mismatched key was causing an entire new set
element to be populated. Since this symbol isn't used to apply the diff
in helper/schema, we can simply strip them out.
This mirrors the change made for providers, so that default values can
be inserted into the config by the backend implementation. This is only
the interface and method name changes, it does not yet add any default
values.
The helper/schema handling of lists loses empty string values, but
retains the correct count. Only re-count the values if the count is
missing entirely, and allow our shims to re-populate the zero values.
Terraform core expects a sane state even when the provider returns an
error. Make sure at the prior state is always the default value to
return, and then alway attempt to process any state returned by
provider.Apply.
Previously we were using the type name requested in the import to select
the schema, but a provider is free to return additional objects of other
types as part of an import result, and so it's important that we perform
schema selection separately for each returned object.
If we don't do this, we get confusing downstream errors where the
resulting object decodes to the wrong type and breaks various invariants
expected by Terraform Core.
The testResourceImportOther test in the test provider didn't catch this
previously because it happened to have an identical schema to the other
resource type being imported. Now the schema is changed and also there's
a computed attribute we can set as part of the refresh phase to make sure
we're completing the Read call properly during import. Refresh was working
correctly, but we didn't have any tests for it as part of the import flow.
With the new diff.Apply we can keep the diff mostly intact, but we need
turn off all RequiresNew flags so that the prior state is not removed
from the apply.
One quirky aspect of our import feature is that we allow the importer to
produce additional resources alongside the one that was imported, such as
to create separate rules for each rule of an imported security group.
Providers need to be able to set the types of these other resources since
they may not match the "main" resource type. They do this by calling
ResourceData.SetType, which in turn sets InstanceState.Ephemeral.Type.
In our shims here we therefore need to copy that out into our new TypeName
field so that the new core import code can see it and create the right
type in the state.
Testing this required a minor change to the test harness to allow the
ImportStateCheck function to see the resource type.
If there were no matching keys, and there was no diff at all, don't set
a zero count for the container. Normally Providers can't reliably detect
empty vs unset here, but there are some cases that worked.
This is a HCL feature rather than a Terraform feature really, but we want
to make sure it keeps working consistently in future versions of Terraform
so this is a Terraform-flavored test for the block expansion behavior.
In particular, it tests that a nested dynamic block can access the parent
iterator, so that we won't regress #19543 in future.
In prior versions of Terraform we permitted inconsistent use of indexes
in resource references, but in as of 0.12 the index usage must correlate
properly with whether "count" is set on the resource.
Since users are likely to have existing configurations with incorrect
usage, here we introduce some specialized error messages for situations
where we can detect such issues statically. This seems to cover all of the
common patterns we've seen in practice.
Some usage patterns will fall back on a less-helpful dynamic error here,
but no configurations coming from 0.11 can end up that way because 0.11
did not permit forms such as aws_instance.no_count[count.index].bar that
this validation would not be able to "see".
Our configuration upgrade tool also contains a fix for this already, but
it takes a more conservative approach of adding the index [1] rather than
[count.index] because it can't be sure (without human help) if correlation
of indices is what was intended.
Terraform used to provide empty diffs to the provider when calculating
`ignore_changes`, which would cause some DiffSuppressFunc to fail, as
can be seen in #18209.
Verify that this is no longer the case in 0.12
Booleans in the legacy form were stored as strings, and can appear as
the incorrect type in the new type system.
Unset fields in sets also might show up erroneously in diffs, with
equal old and new values.
This work was done against APIs that were already changed in the branch
before work began, and so it doesn't apply to the v0.12 development work.
To allow v0.12 to merge down to master, we'll revert this work out for now
and then re-introduce equivalent functionality in later commits that works
against the new APIs.
Various things drifted since these tests were originally written. This
catches them up to the latest implementations of state decoding,
upgrading, etc.
Due to how often the state and plan types are referenced throughout
Terraform, there isn't a great way to switch them out gradually. As a
consequence, this huge commit gets us from the old world to a _compilable_
new world, but still has a large number of known test failures due to
key functionality being stubbed out.
The stubs here are for anything that interacts with providers, since we
now need to do the follow-up work to similarly replace the old
terraform.ResourceProvider interface with its replacement in the new
"providers" package. That work, along with work to fix the remaining
failing tests, will follow in subsequent commits.
The aim here was to replace all references to terraform.State and its
downstream types with states.State, terraform.Plan with plans.Plan,
state.State with statemgr.State, and switch to the new implementations of
the state and plan file formats. However, due to the number of times those
types are used, this also ended up affecting numerous other parts of core
such as terraform.Hook, the backend.Backend interface, and most of the CLI
commands.
Just as with 5861dbf3fc49b19587a31816eb06f511ab861bb4 before, I apologize
in advance to the person who inevitably just found this huge commit while
spelunking through the commit history.
* builtin/providers: implement terraform remote state datasource as providers.Interface
* append and return diags separately (to match the idiomatic usage
elsewhere in Terraform)
* diagnostic summary style improvements
* update tests to pass config to schema.CoerceValue
* trust that the schema will be enforced and there is no need to check
that a given attribute exists
* added dataSourceRemoteStateGetSchema() (effectively replacing a
function that was inappropriately removed) for consistency with other
terraform providers
* builtin/provider terraform test: added InternalValidate() test for dataSourceRemoteStateGetSchema
The new config loader requires some steps to happen in a different
order, particularly in regard to knowing the schema in order to
decode the configuration.
Here we lean directly on the configschema package, rather than
on helper/schema.Backend as before, because it's generally
sufficient for our needs here and this prepares us for the
helper/schema package later moving out into its own repository
to seed a "plugin SDK".
The `remote` backend config contains an attribute that is defined as a `*schema.Set`, but currently only `string` values are accepted as the `config` attribute is defined as a `schema.TypeMap`.
Additionally the `b.Validate()` method wasn’t called to prevent a possible panic in case of unexpected configurations being passed to `b.Configure()`.
This commit is a bit of a hack to be able to support this in the 0.11 series. The 0.12 series will have proper support, so when merging 0.12 this should be reverted again.
The "terraform" provider was previously split out into its own repository,
but that turned out to be a mistake due to how tightly it depends on
aspects of Terraform Core.
Here we prepare to bring it back into the core repository by reorganizing
the directory layout to conform with what's expected there.
Added a list SetNew test to try and reproduce issues testing diff
customization with the Nomad provider. We are running into "diffs didn't
match during apply", with the plan diff exhibiting a strange
off-by-one-type error in a list diff:
datacenters.#: "1" => "2"
datacenters.0: "dc1" => "dc2"
datacenters.1: "" => "dc3"
datacenters.2: "" => "dc3"
The test here does not reproduce that issue, unfortunately, but should
help pinpoint the root cause through elimination.
Restoring the naming of this field in the resource back to
CustomizeDiff, as this is generally more descriptive of the process
that's happening, despite the lengthy name.
To keep with the current convention of most other schema.Resource
functional fields being fairly short, CustomizeDiff has been changed to
"Review". It would be "Diff", however it is already used by existing
functions in schema.Provider and schema.Resource.
It's alive! CustomizeDiff logic now has been inserted into the diff
process. The test_resource_with_custom_diff resource provides some basic
testing and a reference implementation.
There should now be plenty of test coverage for this feature via the
tests added for ResourceDiff, and the basic test added to the
schemaMap.Diff test, and the test resource, but more can be added to
test any specific case that comes up otherwise.
All providers moved to new repos.
Added README, which also serves to preserve the directory in git in
cacse we want to add select providers back into core (e.g. null,
template, test)
We are moving away from using the term "environment" to describe separate
named states for a single config, using "workspace" instead. The old
attribute name remains supported for backward compatibility, but is
marked as deprecated.
Martin Atkins