branch-deletion-pr-creation.yml

name: Branch Deletion Phase One (PR Creation)
permissions:
  contents: write
  pull-requests: write
on:
  schedule:
    - cron: '00 22 1 * *'  # 10PM on 1st of every month
  workflow_dispatch:
    inputs:
      min_age_days:
        description: "Minimum age in days since merge"
        required: true
        default: 27
        type: number

jobs:
  identify-branches:
    if: github.repository_owner == 'mendix'
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v6
        with:
          fetch-depth: 0
          token: ${{ secrets.GITHUB_TOKEN }}
          persist-credentials: true

      - name: Setup jq
        run: sudo apt-get install -y jq

      - name: Create timestamp file
        run: |
          echo "Last scan for stale merged branches: $(TZ='Europe/Amsterdam' date +'%Y-%m-%d %H:%M:%S %Z (UTC%:z)')" > branch-cleanup-timestamp.txt

      - name: Fetch all branches
        run: |
          git fetch origin '+refs/heads/*:refs/remotes/origin/*' --prune

      - name: Process branches
        id: branch-data
        env:
          MIN_AGE_DAYS: ${{ github.event.inputs.min_age_days || '27' }}
        run: |
          set -e
          ALL_BRANCHES=$(git branch -r | grep -v "origin/HEAD" | sed 's/origin\///')
          MIN_AGE_DAYS=${MIN_AGE_DAYS:-27}

          echo "MIN_AGE_DAYS=${MIN_AGE_DAYS}"

          PROTECTED_COUNT=0
          MERGED_COUNT=0
          UNMERGED_COUNT=0

          PROTECTED_BRANCHES=()
          MERGED_BRANCHES_TO_PROCESS=()
          BRANCHES_TO_DELETE=()
          BRANCHES_TOO_RECENT=()
          UNMERGED_BRANCHES=()

          CURRENT_DATE=$(date +%Y%m%d)
          echo "CURRENT_DATE=$CURRENT_DATE" >> $GITHUB_ENV

          for BRANCH in $ALL_BRANCHES; do
            branch_lower=$(echo "$BRANCH" | tr '[:upper:]' '[:lower:]')
            if [[ $branch_lower == *backup* || $branch_lower =~ ^(development|main|master|production)(-[0-9]+)?$ ]]; then
              PROTECTED_BRANCHES+=("$BRANCH")
              PROTECTED_COUNT=$((PROTECTED_COUNT+1))
            elif git branch -r --merged origin/development | grep -q "origin/$BRANCH"; then
              MERGED_BRANCHES_TO_PROCESS+=("$BRANCH")
              MERGED_COUNT=$((MERGED_COUNT+1))
            else
              UNMERGED_BRANCHES+=("$BRANCH")
              UNMERGED_COUNT=$((UNMERGED_COUNT+1))
            fi
          done

          echo "branch totals: protected=${PROTECTED_COUNT} merged=${MERGED_COUNT} unmerged=${UNMERGED_COUNT}"

          for BRANCH in "${MERGED_BRANCHES_TO_PROCESS[@]}"; do
            MERGE_HASH=$(git log --grep="Merge branch.*$BRANCH" origin/development -n 1 --pretty=format:"%H" || true)
            if [ -z "$MERGE_HASH" ]; then
              MERGE_HASH=$(git log -n 1 origin/$BRANCH --pretty=format:"%H" || true)
            fi

            if [ -z "$MERGE_HASH" ]; then
              echo "WARN: no merge commit found for $BRANCH — skipping"
              UNMERGED_BRANCHES+=("$BRANCH (no-merge-hash)")
              UNMERGED_COUNT=$((UNMERGED_COUNT+1))
              continue
            fi

            MERGE_DATE_EPOCH=$(git show -s --format=%ct $MERGE_HASH 2>/dev/null || true)
            if [ -z "$MERGE_DATE_EPOCH" ]; then
              echo "WARN: could not read commit date for $BRANCH (hash=$MERGE_HASH) — skipping"
              UNMERGED_BRANCHES+=("$BRANCH (no-merge-date)")
              UNMERGED_COUNT=$((UNMERGED_COUNT+1))
              continue
            fi

            DAYS_AGO=$(( ($(date +%s) - MERGE_DATE_EPOCH) / 86400 ))

            if [[ $DAYS_AGO -ge $MIN_AGE_DAYS ]]; then
              BRANCHES_TO_DELETE+=("$BRANCH (${DAYS_AGO}d since merge)")
            else
              BRANCHES_TOO_RECENT+=("$BRANCH (${DAYS_AGO}d since merge)")
            fi
            echo "checked $BRANCH: hash=$MERGE_HASH date=$MERGE_DATE_EPOCH days=${DAYS_AGO}"
          done

          echo "HAS_BRANCHES=$([ ${#BRANCHES_TO_DELETE[@]} -gt 0 ] && echo true || echo false)" >> $GITHUB_ENV
          echo "BRANCHES_TO_DELETE=$(printf -- '- %s\n' "${BRANCHES_TO_DELETE[@]}" | jq -Rs .)" >> $GITHUB_ENV
          echo "PROTECTED_BRANCHES=$(printf -- '- %s\n' "${PROTECTED_BRANCHES[@]}" | jq -Rs .)" >> $GITHUB_ENV
          echo "BRANCHES_TOO_RECENT=$(printf -- '- %s\n' "${BRANCHES_TOO_RECENT[@]}" | jq -Rs .)" >> $GITHUB_ENV
          echo "UNMERGED_BRANCHES=$(printf -- '- %s\n' "${UNMERGED_BRANCHES[@]}" | jq -Rs .)" >> $GITHUB_ENV

      - name: Create Deletion PR
        if: env.HAS_BRANCHES == 'true'
        uses: peter-evans/create-pull-request@v8 # NOTE: If you upgrade the version of this action, you must also update the GitHub Actions allowlist in mendix/docs > Settings > Actions > General to permit the new version tag, otherwise the workflow will fail.
        with:
          token: ${{ secrets.GITHUB_TOKEN }}
          title: "[Auto] Branch Deletion Candidates - ${{ env.CURRENT_DATE }}"
          body: |
            ### Branches for Deletion
            ${{ fromJSON(env.BRANCHES_TO_DELETE) }}

            ### Protected Branches
            ${{ fromJSON(env.PROTECTED_BRANCHES) }}

            ### Recent Merges (too recent to delete)
            ${{ fromJSON(env.BRANCHES_TOO_RECENT) }}

            ### Unmerged Branches
            ${{ fromJSON(env.UNMERGED_BRANCHES) }}
          base: development
          labels: Internal WIP
          assignees: MarkvanMents,OlufunkeMoronfolu
          reviewers: MarkvanMents,OlufunkeMoronfolu
          commit-message: "Add branch cleanup candidates for ${{ env.CURRENT_DATE }}"
          add-paths: |
            branch-cleanup-timestamp.txt
          author: "github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>"
          committer: "github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>"