Several top-level block types in the Terraform language have a body where
two different schemas are overlayed on top of one another: Terraform first
looks for "meta-arguments" that are built into the language, and then
evaluates all of the remaining arguments against some externally-defined
schema whose content is not fully controlled by Terraform.
So far we've been cautiously adding new meta-arguments in these namespaces
after research shows us that there are relatively few existing providers
or modules that would have functionality masked by those additions, but
that isn't really a viable path forward as we prepare to make stronger
compatibility promises.
In an earlier commit we've introduced the foundational parts of a new
language versioning mechanism called "editions" which should allow us to
make per-module-opt-in breaking changes in the future, but these shared
namespaces remain a liability because it would be annoying if adopting a
new edition made it impossible to use a feature of a third-party provider
or module that was already using a name that has now become reserved in
the new edition.
This commit introduces a new syntax intended to be a rarely-used escape
hatch for that situation. When we're designing new editions we will do our
best to choose names that don't conflict with commonly-used providers and
modules, but there are many providers and modules that we cannot see and
so there is a risk that any name we might choose could collide with at
least one existing provider or module. The automatic migration tool to
upgrade an existing module to a new edition should therefore detect that
situation and make use of this escaping block syntax in order to retain
the existing functionality until all the called providers or modules are
updated to no longer use conflicting names.
Although we can't put in technical constraints on using this feature for
other purposes (because we don't know yet what future editions will add),
this mechanism is intentionally not documented for now because it serves
no immediate purpose. In effect, this change is just squatting on the
syntax of a special block type named "_" so that later editions can make
use of it without it _also_ conflicting, creating a confusing nested
escaping situation. However, the first time a new edition actually makes
use of this syntax we should then document alongside the meta-arguments
so folks can understand the meaning of escaping blocks produced by
edition upgrade tools.
Passing a provider into a module requires that it be named within the
module. This would previously pass validation, however core would fail
to resolve the provider resulting in an unclear "provider not found"
error.
All the information is available to resolve provider types when building
the configuration, but some provider references still had no FQN. This
caused validation to assume a default type, and incorrectly reject valid
module calls with non-default namespaced providers.
Resolve as much provider type information as possible when loading the
config. Only use this internally for now, but this should be useful
outside of the package to avoid re-resolving the providers later on. We
can come back and find where this might be useful elsewhere, but for now
keep the change as small as possible to avoid any changes in behavior.
We expect that in order to continue to evolve the language without
breaking existing modules we will at some point need to have a way to mark
when a particular module is expecting a newer interpretation of the
language.
Although it's too early to do any deep preparation for that, this commit
aims to proactively reserve an argument named "language" inside
"terraform" blocks, which currently only accepts the keyword TF2021 that
is intended to represent "the edition of the Terraform language as defined
in 2021".
That argument also defaults to TF2021 if not set, so in practice there's
no real reason to set this today, but this minimal validation today is
intended to give better feedback to users of older Terraform versions in
the event that we introduce a new language edition later and they try to
use an module incompatible with their Terraform version.
Add validation which was removed from the configload package, along with
additional validation checks. The output is slightly different, as
instead of validating whether the modules are allowed to have provider
configurations, we validate the various combinations of provider
structures themselves.
Add support for parsing configuration_aliases in required_providers
entries. The decoder needed to be re-written here in order to support
the bare reference style usage of provider names so that they match the
usage in other location within configuration. The only change to
existing handling of the required_providers block is more precise error
locations in a couple cases.
Terraform considers backend configurations only in the root module, so any
declarations in child modules are entirely ignored.
To avoid users mistakenly thinking that a root module backend
configuration has taken effect, we'll now emit a warning about it. This is
a warning rather than an error because it's reasonable to call a module
that would normally be a root module instead as a child module when
writing a wrapper module to handle integration testing.
Remove chef, habitat, puppet, and salt-masterless provsioners,
which follows their deprecation. Update the documentatin for these
provisioners to clarify that they have been removed from later versions
of Terraform. Adds the fmt Make target back and updates fmtcheck script
for correctness.
This builds on an experimental feature in the underlying cty library which
allows marking specific attribtues of an object type constraint as
optional, which in turn modifies how the cty conversion package handles
missing attributes in a source value: it will silently substitute a null
value of the appropriate type rather than returning an error.
In order to implement the experiment this commit temporarily forks the
HCL typeexpr extension package into a local internal/typeexpr package,
where I've extended the type constraint syntax to allow annotating object
type attributes as being optional using the HCL function call syntax.
If the experiment is successful -- both at the Terraform layer and in
the underlying cty library -- we'll likely send these modifications to
upstream HCL so that other HCL-based languages can potentially benefit
from this new capability.
Because it's experimental, the optional attribute modifier is allowed only
with an explicit opt-in to the module_variable_optional_attrs experiment.
Previous deprecations only included direct assignment of template-only
expressions to arguments. That is, this was not deprecated:
locals {
foo = ["${var.foo}"]
}
This commit uses hclsyntax.VisitAll to detect and show deprecations for
all template-only expressions, no matter how deep they are in a given
expression.
The providers schema command is using the Config.ProviderTypes method,
which had not been kept up to date with the changes to provider
requirements detection made in Config.ProviderRequirements. This
resulted in any currently-unused providers being omitted from the
output.
This commit changes the ProviderTypes method to use the same underlying
logic as ProviderRequirements, which ensures that `required_providers`
blocks are taken into account.
Includes an integration test case to verify that this fixes the provider
schemas command bug.
The version argument is deprecated in Terraform v0.14 in favor of
required_providers and will be removed in a future version of terraform
(expected to be v0.15). The provider configuration documentation already
discourages use of 'version' inside provider configuration blocks, so it
only needed an extra note that it is actively deprecated.
An invalid type name in a resource (or data source) could cause a panic
when determining the implied provider for the resource. This commit adds
verification that the type name is valid. It does not add a diagnostic,
since the invalid type name would have already been caught by the
parser.
Fixes#25560
The main motivation here is to produce a helpful error if a user
incorrectly uses the terraform-provider- prefix (which we see on provider
VCS repositories and plugin executables) as part of the source address.
However, this also more broadly blocks "terraform-" as a prefix in
anticipation of whatever instinct causes the phenomenon where e.g.
Python's PyPI has thousands of packages whose names start with "python-",
even though everything on PyPI is for Python by definition. This is
definitely not _necessary_, but it's better to be restrictive at first
and weaken later as needed.
If a resource's "provider" reference is invalid and cannot be parsed, we
should not store the reference as part of a `ProviderConfigRef`. Doing
so creates an invalid data structure, which prevents us from using
`MustParseProviderPart` with the name in later steps.
The invalid test files added in this commit will cause a panic without
the code change.
In a recent PR, we changed the provider requirements code to permit
per-module requirements gathering, to enhance the provider command
output. This had an incorrect implementation of recursive requirements
gathering for the normal case, which resulted in only depth-1 modules
being inspected.
This commit fixes the broken recursion and adds a grandchild module to
the unit tests as test coverage. This also demanded fixing the
testNestedModuleConfigFromDir helper function to cope with nested
modules in test configs.
Providers can be required from multiple sources. The previous
implementation of the providers sub-command displayed only a flat list
of provider requirements, which made it difficult to see which modules
required each provider.
This commit reintroduces the tree display of provider requirements, and
adds a separate output block for providers required by existing state.
All of the feedback from the experiment described enhancements that can
potentially be added later without breaking changes, so this change simply
removes the experiment gate from the feature as originally implemented
with no changes to its functionality.
Further enhancements may follow in later releases, but the goal of this
change is just to ship the feature exactly as it was under the experiment.
Most of the changes here are cleaning up the experiment opt-ins from our
test cases. The most important parts are in configs/experiments.go and in
experiments/experiment.go .
* addrs: replace NewLegacyProvider with NewDefaultProvider in ParseProviderSourceString
ParseProviderSourceString was still defaulting to NewLegacyProvider when
encountering single-part strings. This has been fixed.
This commit also adds a new function, IsProviderPartNormalized, which
returns a bool indicating if the string given is the same as a
normalized version (as normalized by ParseProviderPart) or an error.
This is intended for use by the configs package when decoding provider
configurations.
* terraform: fix provider local names in tests
* configs: validate that all provider names are normalized
The addrs package normalizes all source strings, but not the local
names. This caused very odd behavior if for e.g. a provider local name
was capitalized in one place and not another. We considered enabling
case-sensitivity for provider local names, but decided that since this
was not something that worked in previous versions of terraform (and we
have yet to encounter any use cases for this feature) we could generate
an error if the provider local name is not normalized. This error also
provides instructions on how to fix it.
* configs: refactor decodeProviderRequirements to consistently not set an FQN when there are errors
Previously, resources without explicit provider configuration (i.e. a
`provider =` attribute) would be assigned a default provider based upon
the resource type. For example, a resource `foo_bar` would be assigned
provider `hashicorp/foo`.
This behaviour did not work well with community or partner providers,
with sources configured in `terraform.required_providers` blocks. With
the following configuration:
terraform {
required_providers {
foo = {
source = "acme/foo"
}
}
}
resource foo_bar "a" { }
the resource would be configured with the `hashicorp/foo` provider.
This commit fixes this implied provider behaviour. First we look for a
provider with local name matching the resource type in the module's
required providers map. If one is found, this provider is assigned to
the resource. Otherwise, we still fall back to a default provider.
We now permit at most one `required_providers` block per module (except
for overrides). This prevents users (and Terraform) from struggling to
understand how to merge multiple `required_providers` configurations,
with `version` and `source` attributes split across multiple blocks.
Because only one `required_providers` block is permitted, there is no
need to concatenate version constraints and resolve them. This allows us
to simplify the structs used to represent provider requirements,
aligning more closely with other structs in this package.
This commit also fixes a semantic use-before-initialize bug, where
resources defined before a `required_providers` block would be unable to
use its source attribute. We achieve this by processing the module's
`required_providers` configuration (and overrides) before resources.
Overrides for `required_providers` work as before, replacing the entire
block per provider.
The providers command has been refactored to use the modern provider types and
ProviderRequirements() functions. This resulted in a breaking change to
the output: it no longer outputs the providers by module and no longer
prints `(inherited)` or `(from state)` to show why a provider is
included. We decided that at this time it was best to stick with the
existing functions and make this change, but if we get feedback from the
community we will revisit.
Additional tests to exercise providers in modules and providers from
state have been included.
With provider dependencies now appearing inside a nested block, it seems
likely that configuration examples showing dependencies out of context
will sometimes mislead users into thinking that required_providers is
toplevel.
To give better feedback in that situation, we'll produce a specialized
error in that case hinting the correct structure to the user.
This encapsulates the logic for selecting an implied FQN for an
unqualified type name, which could either come from a local name used in
a module without specifying an explicit source for it or from the prefix
of a resource type on a resource that doesn't explicitly set "provider".
This replaces the previous behavior of just directly calling
NewDefaultProvider everywhere so that we can use a different implication
for the local name "terraform", to refer to the built-in terraform
provider rather than the stale one that's on registry.terraform.io for
compatibility with other Terraform versions.
We've been using the models from the "moduledeps" package to represent our
provider dependencies everywhere since the idea of provider dependencies
was introduced in Terraform 0.10, but that model is not convenient to use
for any use-case other than the "terraform providers" command that needs
individual-module-level detail.
To make things easier for new codepaths working with the new-style
provider installer, here we introduce a new model type
getproviders.Requirements which is based on the type the new installer was
already taking as its input. We have new methods in the states, configs,
and earlyconfig packages to produce values of this type, and a helper
to merge Requirements together so we can combine config-derived and
state-derived requirements together during installation.
The advantage of this new model over the moduledeps one is that all of
recursive module walking is done up front and we produce a simple, flat
structure that is more convenient for the main use-cases of selecting
providers for installation and then finding providers in the local cache
to use them for other operations.
This new model is _not_ suitable for implementing "terraform providers"
because it does not retain module-specific requirement details. Therefore
we will likely keep using moduledeps for "terraform providers" for now,
and then possibly at a later time consider specializing the moduledeps
logic for only what "terraform providers" needs, because it seems to be
the only use-case that needs to retain that level of detail.
* terraform: large refactor to use Provider from configs.Resource
configs.Resource.ImpliedProvider() now returns a string; it is the
callers' responsibility to turn that into an addrs.Provider if needed.
GraphNodeProviderConsumer ProvidedBy() no longer returns nil (reverting
to earlier, pre-provider-fqn behavior): it will return either the
provider set in config, provider set in state, or the default provider.
* configs: parse provider source string during module merge
This was the smallest unit of work needed to start writing provider
source tests!
* Update configs/parser_test.go
Co-Authored-By: Alisdair McDiarmid <alisdair@users.noreply.github.com>
The provider FQN is becoming our primary identifier for a provider, so
it's important that we are clear about the equality rules for these
addresses and what characters are valid within them.
We previously had a basic regex permitting ASCII letters and digits for
validation and no normalization at all. We need to do at least case
folding and UTF-8 normalization because these names will appear in file
and directory names in case-insensitive filesystems and in repository
names such as on GitHub.
Since we're already using DNS-style normalization and validation rules
for the hostname part, rather than defining an entirely new set of rules
here we'll just treat the provider namespace and type as if they were
single labels in a DNS name. Aside from some internal consistency, that
also works out nicely because systems like GitHub use organization and
repository names as part of hostnames (e.g. with GitHub Pages) and so
tend to apply comparable constraints themselves.
This introduces the possibility of names containing letters from alphabets
other than the latin alphabet, and for latin letters with diacritics.
That's consistent with our introduction of similar support for identifiers
in the language in Terraform 0.12, and is intended to be more friendly to
Terraform users throughout the world that might prefer to name their
products using a different alphabet. This is also a further justification
for using the DNS normalization rules: modern companies tend to choose
product names that make good domain names, and now such names will be
usable as Terraform provider names too.
* 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>
Martin Atkins