How to shallow merge map variables?

[lmilbaum]

I'd like to pass variables to terraform like in the following code snippet. Terragrunt or Terraform ignores the maps such that the generated tfvars doesn't include those Complex-typed Values. Would appreciate a lead how to resolve it.

terraform {
  source = "https://github.com/platform-engineering-org/terraform-gitlab-runners-module.git//"
}

include "root" {
  path = find_in_parent_folders()
}

locals {
  environment_vars = read_terragrunt_config(find_in_parent_folders("env.hcl"))
}

inputs = merge(
  local.environment_vars.locals,
  {
    aws_region           = "eu-west-2"
    runner_name          = "pe-prod-bootc-org-arm-runner"
    iam_profile_name     = "pe-prod-bootc-org-gitlab-arm-runners"
    runner_version       = "16.10.0"
    runner_instance_type = "m7g.medium"
    runner_ami_filter = {
      name = ["amzn2-ami-hvm-2.*-arm64-gp2"]
    }
    runner_worker_docker_machine_instance_types = ["m7g.medium"]
    runner_worker_docker_machine_ami_filter = {
      name = ["amzn2-ami-hvm-2.*-arm64-gp2"]
    }
  }
)

---

Tracked in ticket #110885

[lmilbaum]

According to the documentation [1], a type constraint should be specified.
As far as I can see, the type constraint is specified in the dependent module [2].
My module [3] is using the dependent module.

[1] https://terragrunt.gruntwork.io/docs/reference/config-blocks-and-attributes/#inputs
[2] https://terragrunt.gruntwork.io/docs/reference/config-blocks-and-attributes/#inputs
[3] https://github.com/platform-engineering-org/terraform-gitlab-runners-module

[lmilbaum]

As soon as I copied (duplicated code) the variables definitions to my module [3], terragrunt generated the expected results.

{
  "aws_region": "eu-west-2",
  "environment": "bootc-org-arm",
  "runner_ami_filter": {
    "name": [
      "amzn2-ami-hvm-2.*-arm64-gp2"
    ]
  },
  "runner_instance_type": "m7g.medium",
  "runner_name": "pe-prod-bootc-org-arm-runner",
  "runner_version": "16.10.0",
  "runner_worker_docker_machine_ami_filter": {
    "name": [
      "amzn2-ami-hvm-2.*-arm64-gp2"
    ]
  },
  "runner_worker_docker_machine_instance_types": [
    "m7g.medium"
  ],
  "user": "lmilbaum"
}