check-for-updates.yml

name: Check for tzdata updates

on:
  pull_request:
  schedule:
    - cron: '0 9 * * *'  # Runs daily at 9AM UTC
  workflow_dispatch:

jobs:
  check-pr-exists:
    runs-on: ubuntu-latest
    outputs:
      pr_exists: ${{ steps.check_pr_exists.outputs.pr_exists }}
    steps:
      - name: Check if PR already exists
        id: check_pr_exists
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          PR_EXISTS=$(gh pr --repo $GITHUB_REPOSITORY \
                      list --search "Update tzdata to version" \
                      --json number --jq '.[] | .number')
          if [ -n "$PR_EXISTS" ]; then
            echo "A PR updating the tzdata version already exists: https://github.com/python/tzdata/pulls/${PR_EXISTS}"
            echo "::set-output name=pr_exists::true"
            exit 0
          else
            echo "::set-output name=pr_exists::false"
          fi

  check-for-updates:
    runs-on: ubuntu-latest
    needs: check-pr-exists
    permissions:
      pull-requests: write
    if: needs.check-pr-exists.outputs.pr_exists == 'false'  # Run only if no PR exists
    outputs:
      changes_detected: ${{ steps.check_changes.outputs.changes_detected }}
    steps:
      - name: Check out repository (shallow)
        uses: actions/checkout@v3
        with:
          fetch-depth: 1  # Shallow clone to save time

      - name: Set up Python 3.12
        uses: actions/setup-python@v4
        with:
          python-version: '3.12'

      - name: Install dependencies
        run: |
          python -m pip install tox
          sudo apt-get install gh

      - name: Run tox update
        run: tox -e update -- --no-skip-existing

      - name: Check for repository changes and commit
        id: check_changes
        run: |
          git config --global user.email "action@github.com"
          git config --global user.name "GitHub Action"

          # Check for changes
          if git diff --quiet; then
            echo "No changes detected."
            echo "::set-output name=changes_detected::false"
            exit 0
          fi

          echo "Test" > news.d/2024c.md

          # Check for changes in the news.d directory
          git add -A
          news_files=$(git diff --cached --name-only --diff-filter=A | grep '^news.d/.*\.md' || true)

          if [ -z "$news_files" ]; then
            echo "No new file in news.d, failing the job."
            exit 1
          fi

          if [ $(echo "$news_files" | wc -l) -ne 1 ]; then
            echo "More than one new file added in news.d, failing the job."
            exit 1
          fi
          echo "::set-output name=changes_detected::true"

          # Extract TZDATA_VERSION from filename
          TZDATA_VERSION=$(basename "$news_files" .md)

          # Extract TZDATA_NEWS from file content
          TZDATA_NEWS=$(cat "$news_files")

          echo "TZDATA_VERSION=$TZDATA_VERSION" >> $GITHUB_ENV
          echo "TZDATA_NEWS=$TZDATA_NEWS" >> $GITHUB_ENV

      - name: Create PR
        id: commit_changes
        if: steps.check_changes.outputs.changes_detected == 'true'
        run: |
          git commit -m "Update tzdata to version $TZDATA_VERSION" \
                     -m "$TZDATA_NEWS"

      - name: Create pull request
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        if: steps.check_changes.outputs.changes_detected == 'true'
        run: |
          gh pr create --title "Update tzdata to version $TZDATA_VERSION" \
            --body "$TZDATA_NEWS" \
            --base main \
            --head $(git rev-parse --abbrev-ref HEAD) \
            --label "automatic-updates"