create-prs-for-stale-branches.yml

name: "PR: Find branches without PR's"

on:
  push:
    branches:
      - "main"
    paths:
      - ".github/workflows/create-prs-for-stale-branches.yml"
  schedule:
    - cron: "0 1 * * *"

concurrency:
  group: ${{github.workflow}}-${{github.ref}}
  cancel-in-progress: false

jobs:
  build-matrix:
    runs-on: ubuntu-latest

    permissions:
      contents: read

    steps:
      - name: "Initialise Workspace"
        if: startsWith(runner.name, 'buildagent-')
        shell: bash
        run: sudo chown -R "$USER:$USER" "$GITHUB_WORKSPACE"

      - name: "Info"
        shell: bash
        run: |
          echo "Repo: ${{github.repository}}"
          echo "Owner: ${{github.repository_owner}}"

      - name: "Ensure JQ is installed"
        shell: bash
        run: sudo apt install -y jq

      - name: "Checkout Source"
        uses: actions/checkout@v4.1.1
        with:
          fetch-depth: 0
          fetch-tags: true
          ref: main
          repository: ${{github.repository}}

      - name: "Create matrix of branches"
        id: set-matrix
        shell: bash
        run: |
          echo "branches=$(git branch --remote --format='%(refname:short)' | grep -Po 'origin/\K[^*]*' | grep -vE 'HEAD|release/|hotfix/' | jq -R -s -c 'split("\n")[:-1]')" >> "$GITHUB_OUTPUT"
    outputs:
      branches: ${{steps.set-matrix.outputs.branches}}

  check-branch:
    needs: build-matrix
    runs-on: ubuntu-latest

    permissions:
      contents: write
      pull-requests: write

    strategy:
      matrix:
        branch: ${{fromJson(needs.build-matrix.outputs.branches)}}
    env:
      BRANCH: ${{matrix.branch}}
      CREATE_DRAFT: true
      REPO_STATUS: private
    steps:
      - name: "Initialise Workspace"
        if: startsWith(runner.name, 'buildagent-')
        shell: bash
        run: sudo chown -R "$USER:$USER" "$GITHUB_WORKSPACE"

      - name: "Checkout Source"
        uses: actions/checkout@v4.1.1
        with:
          fetch-depth: 0
          fetch-tags: true
          ref: main
          repository: ${{github.repository}}

      - name: "Check Repo Visibility"
        if: github.repository_owner != 'funfair-tech'
        uses: credfeto/action-repo-visibility@v1.2.0
        id: visibility
        with:
          repository: ${{github.repository}}
          token: ${{secrets.SOURCE_PUSH_TOKEN}}

      - name: "Override DRAFT Flag"
        if: github.repository_owner != 'funfair-tech' && env.REPO_STATUS == 'private'
        shell: bash
        run: echo "CREATE_DRAFT=false" >> "$GITHUB_ENV"

      - name: "Branch Detection"
        id: detection
        shell: bash
        run: |
          echo "defaultbranch=$(git remote show origin | grep -Po 'HEAD\sbranch:\s+\K[^.*]*')" >> "$GITHUB_OUTPUT"
          echo "DEFAULT_BRANCH=$(git remote show origin | grep -Po 'HEAD\sbranch:\s+\K[^.*]*')" >> "$GITHUB_ENV"

      # On Default branch
      - name: "On Default Branch"
        if: steps.detection.outputs.defaultbranch == matrix.branch
        uses: actions/github-script@v7.0.1
        with:
          script: |
            core.info("On Default branch - don't do anything");

      # On Non-Default branch
      - name: "On Non-Default branch"
        if: steps.detection.outputs.defaultbranch != matrix.branch
        uses: actions/github-script@v7.0.1
        with:
          script: |
            core.info('On non-default branch');

      - name: "Find Existing PR"
        if: steps.detection.outputs.defaultbranch != matrix.branch
        uses: juliangruber/find-pull-request-action@v1.9.0
        id: find-pull-request
        with:
          branch: "${{env.BRANCH}}"

      - name: "Display Found PR"
        if: steps.detection.outputs.defaultbranch != matrix.branch
        shell: bash
        run: echo "Pull Request ${{steps.find-pull-request.outputs.number}} (${{steps.find-pull-request.outputs.head-sha}})"
      - name: "Check Branch Status"
        if: steps.detection.outputs.defaultbranch != matrix.branch && steps.find-pull-request.outputs.number == ''
        shell: bash
        run:
          echo "Check to see if ${{env.DEFAULT_BRANCH}} is ahead or behind ${{matrix.branch}}..."
          git rev-list --left-right --count "origin/${{env.DEFAULT_BRANCH}}...origin/${{matrix.branch}}"
          git rev-list --left-right --count "origin/${{env.DEFAULT_BRANCH}}...origin/${{matrix.branch}}" | awk '{ print "${{env.BRANCH}} is behind ${{env.DEFAULT_BRANCH}} by "$1" commit(s)" }'
          git rev-list --left-right --count "origin/${{env.DEFAULT_BRANCH}}...origin/${{matrix.branch}}" | awk '{ print "${{matrix.BRANCH}} is ahead of ${{env.DEFAULT_BRANCH}} by "$2" commit(s)" }'
        env:
          DEFAULT_BRANCH: ${{steps.detection.outputs.defaultbranch}}
      - name: "Get last update time of branch"
        if: steps.detection.outputs.defaultbranch != matrix.branch && steps.find-pull-request.outputs.number == ''
        id: lastupdate
        shell: bash
        run: echo "time=$(git log -1 --format=@%ct origin/${{env.BRANCH}})" >> "$GITHUB_OUTPUT"

      - name: "Check Ahead and Behind Status"
        if: steps.detection.outputs.defaultbranch != matrix.branch && steps.find-pull-request.outputs.number == ''
        id: aheadbehind
        shell: bash
        run: >
          { \
            git rev-list --left-right --count "origin/${{env.DEFAULT_BRANCH}}...origin/${{env.BRANCH}}" \
              | awk '{ print "behind="$1 }' ; \
            git rev-list --left-right --count "origin/${{env.DEFAULT_BRANCH}}...origin/${{env.BRANCH}}" \
              | awk '{ print "ahead="$2 }' ; \
            echo "dayssinceupdate=$((($(date +%s)-$(date +%s --date ${{env.LAST_UPDATE}}))/(3600*24)))" ; \
            echo "COMMIT_MSG=$(git log -1 --pretty=%B "${{env.ORIGIN_DEFAULT_BRANCH}}")" ; \
          } >> "$GITHUB_OUTPUT"
        env:
          DEFAULT_BRANCH: ${{steps.detection.outputs.defaultbranch}}
          ORIGIN_DEFAULT_BRANCH: origin/${{steps.detection.outputs.defaultbranch}}
          LAST_UPDATE: ${{steps.lastupdate.outputs.time}}

      # Non-default - ahead of default branch, and no -re-existing PR then create one.
      - name: "Read PR Template"
        if: |-
          steps.detection.outputs.defaultbranch != matrix.branch
          && steps.find-pull-request.outputs.number == ''
          && steps.aheadbehind.outputs.ahead != 0
          && steps.aheadbehind.outputs.dayssinceupdate > 7
        id: pr-template
        uses: juliangruber/read-file-action@v1.1.7
        with:
          path: ./.github/PULL_REQUEST_TEMPLATE.md

      - name: "Create PR"
        if: |-
          steps.detection.outputs.defaultbranch != matrix.branch
          && steps.find-pull-request.outputs.number == ''
          && steps.aheadbehind.outputs.ahead != 0
          && steps.aheadbehind.outputs.dayssinceupdate > 7
        id: open-pr
        uses: repo-sync/pull-request@v2.12
        with:
          source_branch: ${{matrix.branch}}       # If blank, default: triggered branch
          destination_branch: ${{steps.detection.outputs.defaultbranch}}            # If blank, default: master
          pr_assignee: "${{github.actor}}"    # Comma-separated list (no spaces)
          pr_label: "auto-pr,stale"             # Comma-separated list (no spaces)
          pr_draft: ${{env.CREATE_DRAFT}}                        # Creates pull request as draft
          pr_title: "${{steps.aheadbehind.outputs.COMMIT_MSG}} [No commits for ${{steps.aheadbehind.outputs.dayssinceupdate}} days]"
          pr_body: "${{steps.pr-template.outputs.content}}"
          github_token: ${{github.token}}

      - name: "New PR Details"
        if: |-
          steps.detection.outputs.defaultbranch != matrix.branch
          && steps.find-pull-request.outputs.number == ''
          && steps.aheadbehind.outputs.ahead != 0
          && steps.aheadbehind.outputs.dayssinceupdate > 7
        uses: actions/github-script@v7.0.1
        with:
          script: |
            core.info('URL: ${{steps.open-pr.outputs.pr_url}}');
            core.info('PR: ${{steps.open-pr.outputs.pr_number}}');
            core.info('CF: ${{steps.open-pr.outputs.has_changed_files}}');

      - name: "Update PR Labels"
        if: steps.open-pr.outputs.pr_number != ''
        uses: actions/labeler@v5
        with:
          repo-token: ${{secrets.SOURCE_PUSH_TOKEN}}
          configuration-path: .github/labeler.yml
          sync-labels: true
          pr-number: ${{steps.open-pr.outputs.pr_number}}

      - name: "Rebase"
        if: |-
          steps.detection.outputs.defaultbranch != matrix.branch
          && steps.find-pull-request.outputs.number == ''
          && steps.aheadbehind.outputs.behind != 0
          && steps.aheadbehind.outputs.ahead != 0
          && steps.aheadbehind.outputs.dayssinceupdate > 7
        uses: actions/github-script@v7.0.1
        with:
          script: |
            core.info('Rebase?');

      - name: "Delete Branch"
        if: |-
          steps.detection.outputs.defaultbranch != matrix.branch
          && steps.find-pull-request.outputs.number == ''
          && steps.aheadbehind.outputs.ahead == '0'
          && steps.aheadbehind.outputs.dayssinceupdate > 60
        uses: dawidd6/action-delete-branch@v3.1.0
        with:
          github_token: ${{secrets.SOURCE_PUSH_TOKEN}}
          branches: ${{matrix.branch}}

      - name: "Statistics"
        if: |-
          steps.detection.outputs.defaultbranch != matrix.branch
          && steps.find-pull-request.outputs.number == ''
        uses: actions/github-script@v7.0.1
        with:
          script: |
            core.info('Ahead: ${{steps.aheadbehind.outputs.ahead}}');
            core.info('Behind: ${{steps.aheadbehind.outputs.behind}}');
            core.info('Last Commit: ${{steps.aheadbehind.outputs.dayssinceupdate}} days ago');