Dynamic write-only attribute can't be assigned by ephemeral values internally

[magodo]

Terraform Version

v1.12.0-dev (8865218ccb584267a558b4d0c6f0c14a2d1aefd0)

Terraform Configuration Files

terraform {
  required_providers {
    restful = {
      source = "magodo/restful"
    }
  }
}

provider "restful" {
  base_url = "http://local:3000"
}

ephemeral "restful_resource" "test" {
  path = "/ephemerals"
  method = "POST"

  renew_path = "/ephemerals/$(body.id)"
  renew_method = "PATCH"
  renew_body = {
      renew = 1
  }

  expiry_type = "duration"
  expiry_locator = "exact.1s"

  close_path = "/ephemerals/$(body.id)"
  close_method = "DELETE"
}

resource "restful_resource" "test" {
  path = "/resources"
  read_path = "/resources/$(body.id)"
  body = {
      foo = "bar"
  }
  ephemeral_body = {
    secret = ephemeral.restful_resource.test.output.id
  }
}

Debug Output

╷
│ Error: Invalid use of ephemeral value
│
│   with restful_resource.test,
│   on main.tf line 30, in resource "restful_resource" "test":
│   30: resource "restful_resource" "test" {
│
│ Ephemeral values are not valid for "ephemeral_body.secret", because it is not an assignable
│ attribute.
╵

Expected Behavior

Terraform should accept this config as ephemeral_body is marked as WriteOnly: true, albeit it is of dynamic type.

Actual Behavior

terraform validate failed with error:

╷
│ Error: Invalid use of ephemeral value
│
│   with restful_resource.test,
│   on main.tf line 30, in resource "restful_resource" "test":
│   30: resource "restful_resource" "test" {
│
│ Ephemeral values are not valid for "ephemeral_body.secret", because it is not an assignable
│ attribute.
╵

Steps to Reproduce

1. Checkout and build the magodo/terraform-provider-restful at branch: https://github.com/magodo/terraform-provider-restful/tree/ephemeral_body
2. Instruct terraform to use the locally built provider via modifying the .terraformrc
3. terraform validate with the config above

Additional Context

Since the write-only attribute support PR is merged in FW recently, I'm trying to support that in my restful provider.

The provider offers a general resource restful_resource, whose body is defined as a dynamic value. For the same reason, I've introduced a new optional attribute ephemeral_body which has the WriteOnly: true, and is also a dynamic value. I expect as long the ephemeral_body is marked as write-only, then it can reference a ephemeral value.

However, it turns out I can only directly assign an ephemeral value to ephemeral_body, but can't assign it to a nested field. I find the error is raised from Terraform, therefore submitting the issue here.

References

No response

Generative AI / LLM assisted development?

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