coalesce-based workaround for import vs non-var entities?

[handlerbot]

We're doing approximately this:

constants/main.tf

output "aws_account_id" {
  value = "0123456789012"
}

global/main.tf

module "constants" {
  source = "../constants"
}

provider "aws" {
  region = "us-west-2"

  allowed_account_ids = [
    "${module.constants.aws_account_id)}",
  ]
}

This works great, but of course, it breaks terraform import because of the provider's dependency on an interpolation from a source that isn't a variable.

I'm wondering how difficult it would be to modify ImportProviderValidateTransformer to consider this construct safe:

  allowed_account_ids = [
    "${coalesce(var.import_aws_account_id, module.constants.aws_account_id)}",
  ]

This would let us use modules-as-constants as we are happily doing so during normal operation, but for (rare) times when we're importing, we can make our existing config work via:

terraform import -var import_aws_account_id=0123456789012 ...

I'm glad to try and do the work if there are indications that a) it's possible given the data structures exposed to ImportProviderValidateTransformer and b) it would be reasonably likely to be accepted if I can get it working. :-)

Thanks for reading!