* terraform: improve provider config related error messages with nil
config
If there is no provider configuration present in the config at all,
errors related to missing required arguments lack source information or
even a reference to the provider in question. This PR adds more specific
error messages in three of these situations:
- ValidateProvider
- ConfigureProvider: provider.PrepareProviderConfig
- ConfigureProvider: ctx.ConfigureProvider
To test the last case I added a ConfigureProviderFn to the MockContext.
* remove newlines and let the diagnost renderer handle fit
Since plan uses the state as a scratch space for evaluation, we need an
entirely separate state to store the refreshed resources values during
planning. Add a RefreshState method to the EvalContext to retrieve a
state used only for refreshing resources.
* terraform: refactor signature of EvalContext.InitProvisioner
Nothing was using the returned provisioners.Interface, so I simplified
the signature.
* terraform: remove provisioner-related EvalTree()s
The various Evals in eval_provisioner were removed from all callers and
replaced with straight-through code.
`NodeValidatableResource.EvalTree()` to `Execute()` was more involved. I
chose to leave the `EvalValidateResource` and `EvalValidateProvisioner`
Eval functions mostly as-is, changing the main function to `.Validate` to
make it clear that these are no longer eval nodes. Eventually I expect
to rename the file (perhaps to just Validate).
As the Graph is walked, the current way to set the context path was to
have the walker return a context from EnterPath. This required that
every node know it's absolute path, which can no longer be the case
during plan when modules have not been expanded.
This introduces a new method called WithPath, which returns a copy of
the context with the internal path updated to reflect the method
argument. Any use of the EvalContext that requires knowing the path will
now panic if it wasn't explicitly set to ensure that evaluations always
occur in the correct path.
Add EvalContext to the GraphWalker interface.
EvalContext returns an EvalContext that has not yet set a path. This
will allow us to enforce that all context operations requiring a module
instance path will require that a path be explicitly set rather than
evaluating within the wrong path.
EvalContext.InitProvider no longer needs the redundant typ String
terraform.contextComponentFactory refactored to take an addrs.Provider
instead of a string.
This is not used yet, but in future commits will be used as a
"blackboard" to centrally aggregate the information pertaining to
expansion of resources and modules (using "count" or "for_each") to help
ensure consistent treatment of the expansion process during a graph walk.
In practice this only really makes sense for the plan walk, because the
apply walk doesn't do any dynamic expansion.
* Introduce "Local" terminology for non-absolute provider config addresses
In a future change AbsProviderConfig and LocalProviderConfig are going to
become two entirely distinct types, rather than Abs embedding Local as
written here. This naming change is in preparation for that subsequent
work, which will also include introducing a new "ProviderConfig" type
that is an interface that AbsProviderConfig and LocalProviderConfig both
implement.
This is intended to be largely just a naming change to get started, so
we can deal with all of the messy renaming. However, this did also require
a slight change in modeling where the Resource.DefaultProviderConfig
method has become Resource.DefaultProvider returning a Provider address
directly, because this method doesn't have enough information to construct
a true and accurate LocalProviderConfig -- it would need to refer to the
configuration to know what this module is calling the provider it has
selected.
In order to leave a trail to follow for subsequent work, all of the
changes here are intended to ensure that remaining work will become
obvious via compile-time errors when all of the following changes happen:
- The concept of "legacy" provider addresses is removed from the addrs
package, including removing addrs.NewLegacyProvider and
addrs.Provider.LegacyString.
- addrs.AbsProviderConfig stops having addrs.LocalProviderConfig embedded
in it and has an addrs.Provider and a string alias directly instead.
- The provider-schema-handling parts of Terraform core are updated to
work with addrs.Provider to identify providers, rather than legacy
strings.
In particular, there are still several codepaths here making legacy
provider address assumptions (in order to limit the scope of this change)
but I've made sure each one is doing something that relies on at least
one of the above changes not having been made yet.
* addrs: ProviderConfig interface
In a (very) few special situations in the main "terraform" package we need
to make runtime decisions about whether a provider config is absolute
or local.
We currently do that by exploiting the fact that AbsProviderConfig has
LocalProviderConfig nested inside of it and so in the local case we can
just ignore the wrapping AbsProviderConfig and use the embedded value.
In a future change we'll be moving away from that embedding and making
these two types distinct in order to represent that mapping between them
requires consulting a lookup table in the configuration, and so here we
introduce a new interface type ProviderConfig that can represent either
AbsProviderConfig or LocalProviderConfig decided dynamically at runtime.
This also includes the Config.ResolveAbsProviderAddr method that will
eventually be responsible for that local-to-absolute translation, so
that callers with access to the configuration can normalize to an
addrs.AbsProviderConfig given a non-nil addrs.ProviderConfig. That's
currently unused because existing callers are still relying on the
simplistic structural transform, but we'll switch them over in a later
commit.
* rename LocalType to LocalName
Co-authored-by: Kristin Laemmert <mildwonkey@users.noreply.github.com>
The existing "type" argument allows specifying a type constraint that
allows for some basic validation, but often there are more constraints on
a variable value than just its type.
This new feature (requiring an experiment opt-in for now, while we refine
it) allows specifying arbitrary validation rules for any variable which
can then cause custom error messages to be returned when a caller provides
an inappropriate value.
variable "example" {
validation {
condition = var.example != "nope"
error_message = "Example value must not be \"nope\"."
}
}
The core parts of this are designed to do as little new work as possible
when no validations are specified, and thus the main new checking codepath
here can therefore only run when the experiment is enabled in order to
permit having validations.
Previously we were using the experimental HCL 2 repository, but now we'll
shift over to the v2 import path within the main HCL repository as part of
actually releasing HCL 2.0 as stable.
This is a mechanical search/replace to the new import paths. It also
switches to the v2.0.0 release of HCL, which includes some new code that
Terraform didn't previously have but should not change any behavior that
matters for Terraform's purposes.
For the moment the experimental HCL2 repository is still an indirect
dependency via terraform-config-inspect, so it remains in our go.sum and
vendor directories for the moment. Because terraform-config-inspect uses
a much smaller subset of the HCL2 functionality, this does still manage
to prune the vendor directory a little. A subsequent release of
terraform-config-inspect should allow us to completely remove that old
repository in a future commit.
Chaange ResourceProvider to providers.Interface starting from the
context, and fix all type errors.
This only replaced some of method calls directly applicable to the
providers themselves. The resource methods will follow.
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.
The "config" package is no longer used and will be removed as part
of the 0.12 release cleanup. Since configschema is part of the
"new world" of configuration modelling, it makes more sense for
it to live as a subdirectory of the newer "configs" package.
Previously we had the evaluate methods accept directly an
addrs.InstanceKey and had our evaluator infer a suitable value for
count.index for it, but that prevents us from setting the index to be
unknown in the validation scenario where we may not be able to predict
the number of instances yet but we still want to be able to check that
the configuration block is type-safe for all possible count values.
To achieve this, we separate the concern of deciding on a value for
count.index from the concern of evaluating it, which then allows for
other implementations of this in future. For the purpose of this commit
there is no change in behavior, with the count.index value being populated
whenever the instance key is a number.
This commit does a little more groundwork for the future implementation
of the for_each feature (which'll support each.key and each.value) but
still doesn't yet implement it, leaving it just stubbed out for the
moment.
EvaluateBlock and EvaluateExpr are often called multiple times in a single
operation, and our usual approach of mocking with static values is a poor
fit for those cases.
To accommodate more complex tests, we allow the test to optionally provide
a callback function to use instead of the static return values.
Since a pretty common need is to just evaluate the given block or
expression in a simple way, we also now have a helper method
installSimpleEval that installs reasonable implementations of these
two methods that can (assuming no other customization) just evaluate
constant expressions, which is sufficient for many tests.
Some of the objects that are referencable from expressions are transient
values computed only during a graph walk, and not persisted in state. In
order to support arbitrary evaluation of expressions, such as in the
"terraform console" CLI command, it's necessary to be able to evaluate
these values before we start evaluating.
This new Eval method achieves this by performing a special graph walk that
ignores resources (except for dependency resolution) and just focuses on
evaluating all of these transient values, before returning an evaluation
scope that can then resolve expressions in terms of that result.
This replaces the Context.Interpolator method, which was fraught with
various issues due to it not properly priming the state before evaluating.
Due to how deeply the configuration types go into Terraform Core, there
isn't a great way to switch out to HCL2 gradually. As a consequence, this
huge commit gets us from the old state to a _compilable_ new state, but
does not yet attempt to fix any tests and has a number of known missing
parts and bugs. We will continue to iterate on this in forthcoming
commits, heading back towards passing tests and making Terraform
fully-functional again.
The three main goals here are:
- Use the configuration models from the "configs" package instead of the
older models in the "config" package, which is now deprecated and
preserved only to help us write our migration tool.
- Do expression inspection and evaluation using the functionality of the
new "lang" package, instead of the Interpolator type and related
functionality in the main "terraform" package.
- Represent addresses of various objects using types in the addrs package,
rather than hand-constructed strings. This is not critical to support
the above, but was a big help during the implementation of these other
points since it made it much more explicit what kind of address is
expected in each context.
Since our new packages are built to accommodate some future planned
features that are not yet implemented (e.g. the "for_each" argument on
resources, "count"/"for_each" on modules), and since there's still a fair
amount of functionality still using old-style APIs, there is a moderate
amount of shimming here to connect new assumptions with old, hopefully in
a way that makes it easier to find and eliminate these shims later.
I apologize in advance to the person who inevitably just found this huge
commit while spelunking through the commit history.
This is currently not very ergonomic due to the API exposed by providers.
We'll smooth this out in a later change to improve the provider API, since
we know we always want the entire schema.
This turned out to be a big messy commit, since the way providers are
referenced is tightly coupled throughout the code. That starts to unify
how providers are referenced, using the format output node Name method.
Add a new field to the internal resource data types called
ResolvedProvider. This is set by a new setter method SetProvider when a
resource is connected to a provider during graph creation. This allows
us to later lookup the provider instance a resource is connected to,
without requiring it to have the same module path.
The InitProvider context method now takes 2 arguments, one if the
provider type and the second is the full name of the provider. While the
provider type could still be parsed from the full name, this makes it
more explicit and, and changes to the name format won't effect this
code.
Use the configured providers directly, rather than looking for inherited
provider configuration during graph evaluation.
First remove the provider config cache, and the associated
SetProviderConfig and ParentProviderConfig methods on the eval context.
Every provider must be configured, so there's no need to look for
configuration from other provider instances.
The config.ProviderConfig struct now has a Scope field which stores the
proper path for the interpolation scope. To get this metadata to the
interpolator, we add an EvalInterpolatProvider node which can carry the
ProviderConfig, and an InterpolateProvider context method to carry the
ProviderConfig.Scope into the InterplationScope.
Some of the tests could be adjusted to account for the new inheritance
behavior, and some were simply no longer valid and will be removed.
The remaining tests have questions on how they should work in practice.
This mostly concerns orphaned modules where there is no longer a way to
obtain a provider. In some cases we may require that a minimal provider
config be present to handle the destroy process, but we need further
testing.
All disabled code was commented out in this commit to record any
additional comments. The following commit will be a cleanup pass.
This switches to the Go "context" package for cancellation and threads
the context through all the way to evaluation to allow behavior based on
stopping deep within graph execution.
This also adds the Stop API to provisioners so they can quickly exit
when stop is called.
This changes the representation of maps in the interpolator from the
dotted flatmap form of a string variable named "var.variablename.key"
per map element to use native HIL maps instead.
This involves porting some of the interpolation functions in order to
keep the tests green, and adding support for map outputs.
There is one backwards incompatibility: as a result of an implementation
detail of maps, one could access an indexed map variable using the
syntax "${var.variablename.key}".
This is no longer possible - instead HIL native syntax -
"${var.variablename["key"]}" must be used. This was previously
documented, (though not heavily used) so it must be noted as a backward
compatibility issue for Terraform 0.7.
Currently Terraform is leaking goroutines and with that memory. I know
strictly speaking this maybe isn’t a real concern for Terraform as it’s
mostly used as a short running command line executable.
But there are a few of us out there that are using Terraform in some
long running processes and then this starts to become a problem.
Next to that it’s of course good programming practise to clean up
resources when they're not needed anymore. So even for the standard
command line use case, this seems an improvement in resource management.
Personally I see no downsides as the primary connection to the plugin
is kept alive (the plugin is not killed) and only unused connections
that will never be used again are closed to free up any related
goroutines and memory.
