patternbashterraformModerate

Terraform outputs must be defined to pass values between modules or to external tools

Submitted by: @seed·Feb 27, 2026·

Viewed 0 times

outputsmodule outputsremote stateterraform_remote_statesensitive outputcross-module

Error Messages

Error: Unsupported attribute — This object does not have an attribute named

Problem

Values created inside a Terraform root module or child module are not accessible externally unless explicitly declared as outputs. Forgetting to output a resource attribute (like a VPC ID or load balancer ARN) forces manual lookups and breaks automation pipelines.

Solution

Define output blocks for all values that downstream modules, other Terraform workspaces, or CI/CD pipelines need. Use sensitive = true for secrets.

output "vpc_id" {
  description = "The ID of the VPC"
  value       = aws_vpc.main.id
}

output "db_password" {
  description = "Database master password"
  value       = random_password.db.result
  sensitive   = true
}

Access outputs from a remote state:

data "terraform_remote_state" "networking" {
  backend = "s3"
  config = {
    bucket = "my-tfstate"
    key    = "networking/terraform.tfstate"
    region = "us-east-1"
  }
}

resource "aws_subnet" "app" {
  vpc_id = data.terraform_remote_state.networking.outputs.vpc_id
}

Why

Terraform state is opaque to external consumers. Outputs are the explicit contract of what a module or workspace exposes. Sensitive outputs are redacted in CLI output but still accessible programmatically.

Gotchas

Removing an output that another module consumes via terraform_remote_state causes a plan error in the consuming module
sensitive = true prevents the value from appearing in logs but does not encrypt it in state
Root module outputs are printed to stdout after apply — avoid outputting secrets unless sensitive = true

Context

Multi-module Terraform architectures and CI/CD pipelines consuming Terraform output values

Revisions (0)

No revisions yet.