sync-with-upstream.yaml

# Create a PR to sync with the upstream template repo.
# The template repo is https://github.com/jenstroeger/python-package-template.

name: Sync with template repository
on:
  workflow_dispatch:

  schedule:
  - cron: 11 11 * * *

permissions:
  contents: read

jobs:
  sync:
    if: github.repository != 'jenstroeger/python-package-template'
    runs-on: ubuntu-latest
    permissions:
      contents: write
      pull-requests: write
    steps:

    - name: Check out template repository
      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
      with:
        # If you decide to change the upstream template repository to a private one, uncomment
        # the following argument to pass the required token to be able to check it out.
        # token: ${{ secrets.<TEMPLATE_REPO_TOKEN> }}
        repository: jenstroeger/python-package-template
        fetch-depth: 0
        path: template

    - name: Check out current repository
      uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
      with:
        token: ${{ secrets.REPO_ACCESS_TOKEN }}
        fetch-depth: 0
        ref: staging
        path: repo

    - name: Sync with template
      env:
        GH_TOKEN: ${{ secrets.REPO_ACCESS_TOKEN }}
        # This is the username and email for the user who creates a branch and commits
        # the changes. In an organisation that should be a dedicated devops account.
        USER_NAME: jenstroeger
        USER_EMAIL: jenstroeger@users.noreply.github.com
      working-directory: ./repo
      run: |
        LATEST_VERSION=$(cd ../template && git describe --tags --abbrev=0)
        CURRENT_VERSION=$(test -f .github/workflows/.template_version && cat .github/workflows/.template_version || echo "v0.0.0")
        echo "Latest version is ${LATEST_VERSION} and current version is ${CURRENT_VERSION}."

        # Check if the template repo was changed/updated.
        if [ "${CURRENT_VERSION}" == "${LATEST_VERSION}" ]; then
          echo "Unable to find a new version, exiting..."
        else

          # Check if the branch already exists in the current repo.
          BRANCH_NAME="sync-$LATEST_VERSION"
          if [ "$(git rev-parse --verify origin/"""$BRANCH_NAME""" 2>/dev/null)" ]; then
            echo "Branch $BRANCH_NAME already exists, exiting..."
          else

            # Generate a patch file of all template changes in the cloned template repository.
            pushd ../template || exit
            # shellcheck disable=SC2046
            git diff "${CURRENT_VERSION}".."${LATEST_VERSION}" -- $(find . docs/ .github/ .github/workflows/ -maxdepth 1 -type f ! -name "*.md" ! -name ".template_version") > diff.patch
            popd || exit

            # Apply the generated patch to the current repo.
            patch --strip 1 --batch --merge --input ../template/diff.patch || true
            find . -name "*.orig" -type f -delete
            find . -name "*.rej" -type f -delete

            # Create a branch, commit, and push the changeset.
            git checkout -b "$BRANCH_NAME"
            echo "$LATEST_VERSION" > .github/workflows/.template_version
            git add .
            git config --global user.name "$USER_NAME"
            git config --global user.email "$USER_EMAIL"
            git config --list --global # For debug purposes.
            git commit --message "chore: sync with template $LATEST_VERSION"
            git push --set-upstream origin "$BRANCH_NAME"

            # Create the pull request.
            gh pr create --base staging --head "$BRANCH_NAME" --title "chore: sync with template $LATEST_VERSION" --body "This PR was generated automatically."

          fi
        fi