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.
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.
* 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>
* add Config to AttachSchemaTransformer for providerFqn lookup
* terraform: refactor ProvidedBy() to return nil when provider is not set
in config or state
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.
* configs: added map of ProviderLocalNames to configs.Module
We will need to lookup any user-supplied local names for a given FQN.
This PR adds a map of ProviderLocalNames to the Module, along with
adding tests for this and for decodeRequiredProvidersBlock.
This also introduces the appearance of support for a required_provider
"source" attribute, but ignores any user-supplied source and instead
continues to assume that addrs.NewLegacyProvider is the way to go.
Alisdair McDiarmid