Apply after Merge

Terrateam’s Auto-Apply-After-Merge functionality allows you to automatically apply changes to your infrastructure after a pull request has been merged. This can reduce the manual steps required to deploy your changes.

Enabling Auto-Apply-After-Merge

To enable Auto-Apply-After-Merge, you need to configure the when_modified.autoapply setting in your Terrateam configuration file. The when_modified section controls when and how Terrateam responds to changes in your repository.

Add this to your .terrateam/config.yml:

when_modified:
  # Enable auto-apply after merge
  autoapply: true
  # Define which changed files in a pull request trigger a plan operation
  file_patterns: ["**/*.tf", "**/*.tfvars"]
  # All other when_modified options use their default values
  autoplan: true
  autoplan_draft_pr: true

See the when_modified configuration reference for all available options.

How It Works

1. Open a pull request with changes to your Terraform code.

2. Terrateam automatically runs a Plan operation and comments on the pull request with the plan output.

3. Review the plan output and collaborate with your team to ensure the changes are as expected.

4. Once the pull request has been approved and all required checks have passed, merge the pull request.

5. Terrateam detects the merge event and automatically triggers an Apply operation.

6. Terrateam comments on the merged pull request with the apply output, confirming that the changes have been applied.

Customizing Auto-Apply-After-Merge

Selective Auto-Apply

If you want to enable Auto-Apply-After-Merge only for specific directories or workspaces, you can use Dirs and Tags.

For example, in .terrateam/config.yml:

dirs:
  prod:
    tags: [prod]
    when_modified:
      autoapply: true  # Enable auto-apply for production
      file_patterns: ["${DIR}/*.tf"]
  staging:
    tags: [staging]
    when_modified:
      autoapply: false  # Disable auto-apply for staging
      file_patterns: ["${DIR}/*.tf"]

Apply Requirements

Terrateam has a set of Apply Requirements that must be met before an Apply operation can be triggered, even with Auto-Apply-After-Merge enabled.

Here’s an example configuration in .terrateam/config.yml:

apply_requirements:
  create_pending_apply_check: true
  checks:
    - tag_query: ""  # Apply to all directories and workspaces
      approved:
        enabled: true
        any_of: ["team:infrastructure"]
        any_of_count: 2  # Require 2 approvals
      merge_conflicts:
        enabled: true
      status_checks:
        enabled: true
        ignore_matching: []

This configuration:

• Requires 2 approvals from the infrastructure team
• Ensures there are no merge conflicts
• Verifies all status checks have passed

Notifications

When an Auto-Apply-After-Merge operation is triggered, Terrateam will comment on the merged pull request with the apply output. You can also configure additional notifications using Hooks.

Example hook configuration in .terrateam/config.yml:

# Add Slack notifications for auto-apply events
hooks:
  apply:
    post:
      - type: run
        name: "Slack Notification"
        cmd: ['curl', '-X', 'POST', '--data', '{"text":"Auto-apply completed for ${TERRATEAM_PR_TITLE}"}', '${SLACK_WEBHOOK_URL}']

Considerations

• Auto-Apply-After-Merge is a powerful feature that can automate your deployment process, but it’s important to ensure that your Terraform code is thoroughly reviewed and tested before merging.
• If an Auto-Apply-After-Merge operation fails, Terrateam will comment on the merged pull request with the error details.
• Auto-Apply-After-Merge can be disabled at any time by setting when_modified.autoapply to false in your Terrateam configuration file.