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.
* 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>
Pam Selle