release.yml

name: Prepare PR for release

on:
  create

jobs:
  prepare_release_pr:
    if: ${{ contains(github.ref, 'refs/heads/release/') }}
    runs-on: ubuntu-latest
    steps:
    - name: Checkout Github
      uses: actions/checkout@v2
      with:
        fetch-depth: 0

    - name: Extract release version
      id: version
      run: |
        export VERSION=$(basename ${{ github.ref }})
        echo "::set-output name=release_version::$VERSION"

    - name: Create prepare for release commit
      run: |
        echo $(git log --pretty=oneline | cut -d" " -f2- | grep -n -m1 "Prepare for .* release"|cut -d':' -f1)
        nbNewCommits=$(echo "$(git log --pretty=format:%s | grep -n -m1 "Prepare for .* release" | cut -d':' -f1) - 1" | bc)
        newCommits=$(git log --pretty=format:%s|head -$nbNewCommits|sed 's/close #/#/;s/closes #/#/')
        newVersion=${{ steps.version.outputs.release_version }}
        headLine="Version $newVersion ($(date +%Y-%m-%d))"
        nbDashes=$(expr length "$headLine")
        dashes=$(printf "%0.s-" $(seq 1 $nbDashes))
        { echo -e "$headLine\n$dashes\n$newCommits\n"; cat CHANGELOG; } > CHANGELOG.new
        mv CHANGELOG.new CHANGELOG
        git config user.name "github-actions[bot]"
        git config user.email "41898282+github-actions[bot]@users.noreply.github.com"
        git commit -m "Prepare for $newVersion release" CHANGELOG build.sbt README.md
  
    - name: Push changes
      uses: ad-m/github-push-action@master
      with:
        github_token: ${{ secrets.GITHUB_TOKEN }}
        branch: ${{ github.ref }}

    - name: Create PR
      uses: repo-sync/pull-request@v2
      with:
        destination_branch: "master"
        pr_title: "Release ${{ steps.version.outputs.release_version }}"
        pr_body: "Created by Github Actions"
        github_token: ${{ secrets.GITHUB_TOKEN }}