Skip to main content

Cluster Terraform Testing Workflow

A reusable workflow that validates Terraform configurations for cluster deployments by running terraform init, validate, and plan operations to ensure infrastructure code quality and correctness.

Overview​

This workflow provides comprehensive testing of Terraform configurations for cluster deployments. It performs multiple validation steps including format checking, initialization, validation, and planning. Optionally, it can perform a test deployment and cleanup in an isolated environment. The workflow also generates documentation for the Terraform configurations.

Features​

  • Multiple Validation Steps: Runs terraform fmt, init, validate, and plan operations
  • Flexible Backend Configuration: Supports custom backend configuration
  • Variables Support: Allows specifying a variables file for testing
  • Test Deployment Option: Can perform a test apply and destroy cycle
  • Documentation Generation: Automatically generates documentation for Terraform modules
  • Artifact Upload: Saves terraform plan files as artifacts for review

Parameters​

ParameterTypeRequiredDefaultDescription
working-directorystringYesDirectory containing the Terraform configurations
terraform-versionstringNo'1.5.7'Version of Terraform to use
backend-configstringNo'{}'Optional backend configuration parameters (JSON format)
terraform-vars-filestringNo''Optional path to terraform.tfvars file
test-applybooleanNofalseWhether to perform a test apply
test-destroybooleanNotrueWhether to destroy test resources after apply

Outputs​

This workflow does not define explicit outputs, but it does upload the Terraform plan as an artifact.

Dependencies​

This template may depend on the following:

  • Required GitHub Secrets:
  • TERRAFORM_API_TOKEN - For Terraform Cloud integration (if used)
  • Required Tools:
  • terraform-docs - Installed during workflow if not present

Usage​

Basic Usage​

terraform-tests:
  name: Terraform Configuration Tests
  uses: ./.github/workflows/cluster-test-terraform.yml
  with:
    working-directory: 'blueprints/terraform/full-single-cluster'
    terraform-version: '1.5.7'

Advanced Usage​

terraform-tests:
  name: Terraform Configuration Tests
  uses: ./.github/workflows/cluster-test-terraform.yml
  with:
    working-directory: 'blueprints/terraform/full-single-cluster'
    terraform-version: '1.6.0'
    backend-config: '{"key": "my-state-file", "bucket": "my-tf-state"}'
    terraform-vars-file: './test/fixtures/test.tfvars'
    test-apply: true
    test-destroy: true

Implementation Details​

The workflow executes a single job that:

  1. Checks out the repository
  2. Sets up Terraform with the specified version
  3. Checks Terraform formatting
  4. Initializes Terraform with backend configuration
  5. Validates the Terraform configuration
  6. Runs a Terraform plan
  7. Optionally applies the configuration (test deployment)
  8. Optionally destroys deployed resources
  9. Generates documentation for the module
  10. Uploads plan files as artifacts

Key Components​

  • Setup Terraform: Uses HashiCorp's official action to set up the correct Terraform version
  • Backend Configuration: Processes JSON input to generate backend config parameters
  • Variables Handling: Checks for and uses a variables file if specified
  • Documentation Generation: Uses terraform-docs to generate markdown documentation

Error Handling​

  • The workflow will fail if terraform validate or plan operations fail
  • Test destroy operations are run with continue-on-error to ensure the workflow completes even if destroy fails
  • Documentation generation is run with continue-on-error to prevent non-critical failures from failing the workflow

Examples​

Example 1: Matrix Testing of Multiple Modules​

name: Terraform Tests

on:
  pull_request:
    paths:
      - 'blueprints/terraform/**'

jobs:
  changes:
    uses: ./.github/workflows/matrix-folder-check.yml

  terraform-matrix-tests:
    needs: changes
    if: needs.changes.outputs.changesInInstall == 'true'
    strategy:
      matrix: ${{ fromJson(needs.changes.outputs.changedTFFolders) }}
    uses: ./.github/workflows/cluster-test-terraform.yml
    with:
      working-directory: ${{ matrix.folderName }}
      terraform-version: '1.5.7'

Example 2: Test Deployment for Main Branch​

name: Test Deployment

on:
  push:
    branches:
      - main
    paths:
      - 'blueprints/terraform/dev-environment/**'

jobs:
  deploy-test:
    uses: ./.github/workflows/cluster-test-terraform.yml
    with:
      working-directory: 'blueprints/terraform/dev-environment'
      terraform-version: '1.5.7'
      terraform-vars-file: './test/fixtures/dev.tfvars'
      test-apply: true
      test-destroy: true

Troubleshooting​

  1. Terraform Init Failure: Backend configuration issues

    • Solution: Check the backend-config parameter format and credentials

  2. Terraform Plan/Apply Failures: Configuration or provider issues

    • Solution: Review plan output for specific error messages and fix configuration

  3. Documentation Generation Failure: Missing terraform-docs

    • Solution: The workflow should install terraform-docs automatically, but check log for specific errors

Learn More​

🤖 Crafted with precision by ✨Copilot following brilliant human instruction, then carefully refined by our team of discerning human reviewers.