github-enforce-main-to-release.yaml

name: Enforce Main-to-Release Merges

on:
  pull_request:
    # This workflow will run for any PR whose base branch is "release"
    branches: [release]
    types: [opened, synchronize, reopened]

jobs:
  check-source-branch:
    runs-on: ubuntu-latest
    steps:
      - name: Check that PR comes from main branch
        run: |
          echo "PR head branch: ${{ github.event.pull_request.head.ref }}"
          if [ "${{ github.event.pull_request.head.ref }}" != "main" ]; then
            echo "Error: Only PRs originating from the 'main' branch can be merged into 'release'."
            exit 1
          fi