🚀 Terraform PR Comment Action

Run Terraform via PR comments with apply-before-merge workflow

Inspired by Atlantis • Powered by tfcmt

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✨ Features

• 💬 PR Comment Triggered - Execute Terraform via terraform plan or terraform apply comments
• 📦 Multi-Project Support - Manage multiple Terraform projects in one repository
• 🤖 Autoplan - Automatically run plan when Terraform files are modified
• ✅ Requirements Enforcement - Validate mergeable status and approvals before execution
• 📝 Formatted Output - Beautiful PR comments powered by tfcmt

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🚀 Quick Start

1️⃣ Create Workflow File

Create .github/workflows/terraform-pr.yml:

name: Terraform PR

on:
  issue_comment:
    types: [created]
  pull_request:
    types: [opened, synchronize, closed]

permissions:
  contents: read
  pull-requests: write
  issues: write

jobs:
  terraform:
    runs-on: ubuntu-latest
    if: |
      github.event_name == 'pull_request' ||
      (github.event_name == 'issue_comment' &&
       github.event.issue.pull_request &&
       startsWith(github.event.comment.body, 'terraform'))

    steps:
      - name: Checkout PR code
        uses: actions/checkout@v4
        with:
          ref: ${{ github.event.pull_request.head.sha }}

      - name: Setup Terraform
        uses: hashicorp/setup-terraform@v3
        with:
          terraform_version: 1.7.0

      - name: Run terraform-action
        uses: tkasuz/terraform-action@v1.1.0
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          config-path: .terraform-action.yaml

2️⃣ Create Configuration File

Create .terraform-action.yaml:

automerge: true
projects:
  - name: production
    dir: terraform/production
    autoplan:
      enabled: true
      when_modified: ["*.tf", "*.tfvars", ".terraform.lock.hcl"]
    plan_requirements: [mergeable]
    apply_requirements: [mergeable, approved]

  - name: staging
    dir: terraform/staging
    autoplan:
      enabled: true
      when_modified: ["*.tf", "*.tfvars"]
    plan_requirements: [mergeable]
    apply_requirements: [mergeable, approved]

tfcmt:
  enabled: true
  skip_no_changes: true

3️⃣ Use in Pull Requests

Comment on a pull request:

# 📋 Plan all projects
terraform plan

# 📋 Plan specific projects
terraform plan -project=production,staging

# 🚀 Apply all projects
terraform apply

# 🚀 Apply specific project
terraform apply -project=production

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⚙️ Configuration Reference

📁 Project Settings

Field	Required	Description
name	✅	Project name
dir	✅	Directory containing Terraform files
autoplan.enabled	❌	Enable automatic plan on file changes
autoplan.when_modified	❌	File patterns that trigger autoplan
plan_requirements	❌	Requirements for plan (default: [mergeable])
apply_requirements	❌	Requirements for apply (default: [mergeable, approved])

🔐 Requirements

Requirement	Description
mergeable	PR must be mergeable (no conflicts, passing checks)
approved	PR must have at least one approval

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🔧 Troubleshooting

"Terraform is not installed"

Add the hashicorp/setup-terraform step before this action.

"Configuration file not found"

Ensure .terraform-action.yaml exists in your repository root.

"PR requirements not met"

Verify the PR is mergeable and has required approvals.

"Project not found"

Check that project names in -p flag match your config file.

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📄 License

MIT