This adds supports for "unmanaged" providers, or providers with process
lifecycles not controlled by Terraform. These providers are assumed to
be started before Terraform is launched, and are assumed to shut
themselves down after Terraform has finished running.
To do this, we must update the go-plugin dependency to v1.3.0, which
added support for the "test mode" plugin serving that powers all this.
As a side-effect of not needing to manage the process lifecycle anymore,
Terraform also no longer needs to worry about the provider's binary, as
it won't be used for anything anymore. Because of this, we can disable
the init behavior that concerns itself with downloading that provider's
binary, checking its version, and otherwise managing the binary.
This is all managed on a per-provider basis, so managed providers that
Terraform downloads, starts, and stops can be used in the same commands
as unmanaged providers. The TF_REATTACH_PROVIDERS environment variable
is added, and is a JSON encoding of the provider's address to the
information we need to connect to it.
This change enables two benefits: first, delve and other debuggers can
now be attached to provider server processes, and Terraform can connect.
This allows for attaching debuggers to provider processes, which before
was difficult to impossible. Second, it allows the SDK test framework to
host the provider in the same process as the test driver, while running
a production Terraform binary against the provider. This allows for Go's
built-in race detector and test coverage tooling to work as expected in
provider tests.
Unmanaged providers are expected to work in the exact same way as
managed providers, with one caveat: Terraform kills provider processes
and restarts them once per graph walk, meaning multiple times during
most Terraform CLI commands. As unmanaged providers can't be killed by
Terraform, and have no visibility into graph walks, unmanaged providers
are likely to have differences in how their global mutable state behaves
when compared to managed providers. Namely, unmanaged providers are
likely to retain global state when managed providers would have reset
it. Developers relying on global state should be aware of this.
Validation is supposed to be a local-only operation, but Configure implementations
are allowed to make outgoing requests to remote APIs to validate settings.
* import: remove Config from ImportOpts
`Config` in ImportOpts was any provider configuration provided by the
user on the command line. This option has already been removed in favor
of only taking the provider from the configuration loaded in the current
context.
* terrafrom: add Config to ImportStateTransformer and refactor Transform
to get the resource provider FQN from the Config
Implement a new provider_meta block in the terraform block of modules, allowing provider-keyed metadata to be communicated from HCL to provider binaries.
Bundled in this change for minimal protocol version bumping is the addition of markdown support for attribute descriptions and the ability to indicate when an attribute is deprecated, so this information can be shown in the schema dump.
Co-authored-by: Paul Tyng <paul@paultyng.net>
* terraform/context: use new addrs.Provider as map key in provider factories
* added NewLegacyProviderType and LegacyString funcs to make it explicit that these are temporary placeholders
This PR introduces a new concept, provider fully-qualified name (FQN), encapsulated by the `addrs.Provider` struct.
Remove reflect.DeepEqual from path comparisons to get reliable results.
The equality issues were only noticed going the grpc interface, so add a
corresponding test to the test provider.
The helper/schema diff process loses empty strings, causing them to show
up as unset (null) during apply. Besides failing to show as set by
GetOk, the absence of the value also triggers the schema to insert a
default value again during apply.
It would also be be preferable if the defaults weren't re-evaluated
again during ApplyResourceChange, but that would require a more invasive
patch to the field readers, and ensuring the empty string is stored in
the plan should block the default.
When a Diff contains a NewRemoved attribute (which would have been null
in the planned state), the final value is often the "zero" value string
for the type, which the provider itself still applies to the state.
Rather than risking a change of behavior in helper/schema by fixing the
inconsistency, we'll remove the NewRemoved attributes after apply to
prevent further issues resulting from the change in planned value.
The new type system only has a Number type, but helper schema
differentiates between Int and Float values. Verify that a new config
value is an integer during Validate, because the existing WeakDecode
validation will decode a float value into an integer while the config
FieldReader will attempt to parse the float exactly.
Since we're limiting this to protoV5, we can be certain that any valid
config value will be converted to an `int` type by the shims. The only
case where an integral float value will appear is if the integer is out
of range for the systems `int` type, but we also need to prevent that
anyway since it would fail to read in the same manner.
Computed primitive values must see the UnknownConfigValue or they are
assumed to be unchanged. Restrict the usage of the protov5 ComputedKeys
to containers.
We were previously catching some errors at read time, but some type errors
were panicking because the cty.DynamicPseudoType arguments have no
automatic pre-type-checking done but this code was assuming they would
be objects.
Here we add an explicit validation step that includes both the backend
validation we were previously doing during read and some additional
type checking to ensure the two dynamic arguments are suitably-typed.
Having the separate validation step means that these problems can be
detected by "terraform validate", rather than only in "terraform plan"
or "terraform apply".
If a dynamic block (in the HCL dynamic block extension sense) has an
unknown value for its for_each argument, it gets expanded to a single
placeholder block with all of its attributes set to a unknown values.
We can use this as part of a heuristic to relax our object compatibility
checks for situations where the plan included an object that appears to
be (but isn't necessarily) such a placeholder, allowing for the fact that
the one placeholder block could be replaced with zero or more real blocks
once the for_each value is known.
Previously our heuristic was too strict: it would match only if the only
block present was a dynamic placeholder. In practice, users may mix
dynamic blocks with static blocks of the same type, so we need to be more
liberal to avoid generating incorrect incompatibility errors in such
cases.
removeConfigUnknowns need to remove the value completely from the config
map. Removing this value allows GetOk and GetOkExists to indicate if the
value was set in the config in the case of an Optional+Computed
attribute.
We previously attempted to make the special diff apply behavior for nested
sets of objects work with attribute mode by totally discarding attribute
mode for all shims.
In practice, that is too broad a solution: there are lots of other shimming
behaviors that we _don't_ want when attribute mode is enabled. In
particular, we need to make sure that the difference between null and
empty can be seen in configuration.
As a compromise then, we will give all of the shims access to the real
ConfigMode and then do a more specialized fixup within the diff-apply
logic: we'll construct a synthetic nested block schema and then use that
to run our existing logic to deal with nested sets of objects, while
using the previous behavior in all other cases.
In effect, this means that the special new behavior only applies when the
provider uses the opt-in ConfigMode setting on a particular attribute,
and thus this change has much less risk of causing broad, unintended
regressions elsewhere.
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.
Kristin Laemmert