dependabot-auto-approve-and-merge.yml

name: Dependabot PR Approve and Merge
# Source: https://blog.somewhatabstract.com/2021/10/11/setting-up-dependabot-with-github-actions-to-approve-and-merge/?utm_source=pocket_mylist
# See also: https://docs.github.com/en/code-security/supply-chain-security/keeping-your-dependencies-updated-automatically/automating-dependabot-with-github-actions#approve-a-pull-request

on: pull_request_target

permissions:
  pull-requests: write
  contents: write

jobs:
  dependabot:
    runs-on: ubuntu-latest
    # Checking the actor will prevent your Action run failing on non-Dependabot
    # PRs but also ensures that it only does work for Dependabot PRs.
    if: ${{ github.actor == 'dependabot[bot]' }}
    steps:
      # This first step will fail if there's no metadata and so the approval
      # will not occur.
      - name: Dependabot metadata
        id: dependabot-metadata
        uses: dependabot/fetch-metadata@v2.2.0
        with:
          github-token: "${{ secrets.GITHUB_TOKEN }}"
      # Here the PR gets approved.
      - name: Approve a PR
        run: gh pr review --approve "$PR_URL"
        env:
          PR_URL: ${{ github.event.pull_request.html_url }}
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
      # Finally, this sets the PR to allow auto-merging for patch and minor
      # updates if all checks pass
      - name: Enable auto-merge for Dependabot PRs
        if: ${{ steps.dependabot-metadata.outputs.update-type != 'version-update:semver-major' }}
        run: gh pr merge --auto --squash "$PR_URL"
        env:
          PR_URL: ${{ github.event.pull_request.html_url }}
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}