create-release-branch.yaml

name: Create Release Branch

on:
  push:
    tags:
      - 'v[0-9]+.[0-9]+.0' # Trigger on minor release tags (e.g. v1.54.0)
  workflow_dispatch:
    inputs:
      tag:
        description: 'The minor release tag (e.g. v1.54.0)'
        required: true
        type: string

jobs:
  create-release-branch:
    runs-on: ubuntu-latest
    permissions:
      contents: write # Allow pushing the release branch
    steps:
      - name: Determine tag
        id: determine-tag
        run: |
          if [ -n "${{ github.event.inputs.tag }}" ]; then
            TAG=${{ github.event.inputs.tag }}
          else
            TAG=${GITHUB_REF#refs/tags/}
          fi
          if ! [[ "$TAG" =~ ^v[0-9]+\.[0-9]+\.0$ ]]; then
            echo "Error: Tag $TAG is not in the expected format: vX.Y.0"
            exit 1
          fi
          echo "tag=${TAG}" >> "$GITHUB_OUTPUT"

      - name: Define branch name from tag
        id: define-branch
        run: |
          TAG=${{ steps.determine-tag.outputs.tag }}
          echo "branch=release/${TAG%.0}.x" >> "$GITHUB_OUTPUT"

      - name: Checkout dd-trace-java at tag
        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # 6.0.2
        with:
          ref: ${{ steps.determine-tag.outputs.tag }}

      - name: Check if branch already exists
        id: check-branch
        run: |
          BRANCH=${{ steps.define-branch.outputs.branch }}
          if git ls-remote --heads origin "$BRANCH" | grep -q "$BRANCH"; then
            echo "creating_new_branch=false" >> "$GITHUB_OUTPUT"
            echo "Branch $BRANCH already exists - skipping creation"
          else
            echo "creating_new_branch=true" >> "$GITHUB_OUTPUT"
            echo "Branch $BRANCH does not exist - creating it now"
          fi

      - name: Create and push release branch
        if: steps.check-branch.outputs.creating_new_branch == 'true'
        run: |
          git checkout -b "${{ steps.define-branch.outputs.branch }}"
          git push -u origin "${{ steps.define-branch.outputs.branch }}"

      - name: Dispatch repository event to pin system tests
        if: steps.check-branch.outputs.creating_new_branch == 'true'
        uses: peter-evans/repository-dispatch@v4
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          event-type: pin-system-tests
          client-payload: '{"release-branch-name": "${{ steps.define-branch.outputs.branch }}"}'