Terraform Data Source

Definition:

• fetches data about a resource from the provider without provisioning an associated infrastructure object

data block

•     data "<TYPE>" "<LABEL>" {
       <PROVIDER-SPECIFIC ARGUMENTS>
       count = <NUMBER>      # `count` and `for_each` are mutually exclusive
       depends_on = [ <RESOURCE.ADDRESS.EXPRESSION> ]
       for_each = {          # `for_each` and `count` are mutually exclusive
          <KEY> = <VALUE>
       }
       for_each = [       # `for_each` accepts a map or a set of strings
        "<VALUE>",
        "<VALUE>"
       ]
       provider = <REFERENCE.TO.ALIAS>
       lifecycle {
          precondition {
             condition = <EXPRESSION>
             error_message = "<STRING>"
        }
        postcondition {
          condition = <EXPRESSION>
          error_message = "<STRING>"
        }
      }
    }

terraform_remote_state:

• get data from remote/local Terraform State
• only root-level output values from remote state are exposed
• Better to use other data block if possible

•     data "terraform_remote_state" "vpc" {
      backend = "remote"
    
      config = {
        organization = "hashicorp"
        workspaces = {
          name = "vpc-prod"
        }
      }
    }
    
    # Terraform >= 0.12
    resource "aws_instance" "foo" {
      # ...
      subnet_id = data.terraform_remote_state.vpc.outputs.subnet_id
    }