Terraform working with variables

Terraform Notes

Working with Variables

In this example, I am populating a dummy Service Control Policy (SCP) in my Org. As such, I need to provide target ID that is the root's ID.

main.tf

provider "aws" {
  alias    = "master_east_2"
  version = "~> 2.0"
  region  = "us-east-2"
  access_key = "AAAAAAAAAAAAAAAAA"
  secret_key = "ffffffffffffffffffffffffffffffffff"
}

variable "main_target_id" {
    type = string
    default = "r-ppg1"
}

module "org_scp" {
  source = "./module"
  module_target_id = var.main_target_id
  providers = {
    aws = aws.master_east_2
  }  
}

From main.tf, I feed in a local variable called main_target_id with the value "r-ppg1" this is the id of the org root. The module is using a variable called "module_target_id," we define this in the module file in the variable block. The variable block is used to define the type and default, if applicable.


module/module_scp.tf

resource "aws_organizations_policy" "example" {
  name = "example"

  content = <<CONTENT
{
  "Version": "2012-10-17",
  "Statement": {
    "Effect": "Allow",
    "Action": "*",
    "Resource": "*"
  }
}
CONTENT
}

variable "module_target_id" {
    type = string
}

resource "aws_organizations_policy_attachment" "root" {
  policy_id = aws_organizations_policy.example.id
  target_id = var.module_target_id
}

The resource "aws_organizations_policy_attachment" is expecting two arguments policy_id and target_id. These we don't control.