python-bump.yml

name: Increment Version

on:
  workflow_dispatch:
    inputs:
      next-version:
        description: "override with custom version number"
        required: false

env:
  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

jobs:
  bump:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v3
        with:
          fetch-depth: 0

      - run: pipx install poetry

      - uses: actions/setup-python@v4
        with:
          python-version: '3.10.x'
          cache: 'poetry'

      - run: poetry install

      - name: Run bash script
        shell: bash
        run: |
          # Gather new git history from after the last release
          git log --format="%s" > log.txt
          touch subjects.txt
          touch types.txt
          while IFS= read -r LINE; do
            # Read line until colon symbol ( : )
            SUBJECT_TYPE=$(echo $LINE | awk -F: '{print $1}')

            # Stop iterating git log when reaching latest release
            if [[ $SUBJECT_TYPE == 'release' ]]; then
              break
            fi

            # Else continue saving subjects and commit types
            echo "- $LINE" >> subjects.txt
            echo $SUBJECT_TYPE >> types.txt
          done < log.txt


          # Save current release's version
          VERSION=$(poetry version --short)


          # Decide if programmatically finding next version or if manually provided one by user
          METHOD="manual"
          NEXT="${{ github.event.inputs.next-version }}"

          if [[ -z "$NEXT" ]]; then
            METHOD="programmatic"

            # Determine which version number to bump
            BUMP_TYPE="nv" # Meaning non-versioning commit, or affecting something outside the API. Basically ignore the types: build, chore, ci, docs, perf, refactor, revert, style, test.
            while IFS= read -r TYPE; do
              if [[ "$TYPE" == "BREAK" ]]; then
                BUMP_TYPE="major"
                break
              elif [[ "$BUMP_TYPE" != "minor" ]]; then
                if [[ "$TYPE" == "feat" ]]; then
                  BUMP_TYPE="minor"
                elif [[ "$TYPE" == "fix" ]]; then
                  BUMP_TYPE="patch"
                fi
              fi
            done < types.txt

            # Instantiate version numbers
            IFS='.' read -r MAJOR MINOR PATCH <<< "$VERSION"

            # Get version number for next release
            if [ "$BUMP_TYPE" == "major" ]; then
              # Backwards incompatible API changes
              NEXT="$((MAJOR+1)).0.0"
            elif [ "$BUMP_TYPE" == "minor" ]; then
              # Backwards compatible API additions/changes
              NEXT="$MAJOR.$((MINOR+1)).0"
            elif [ "$BUMP_TYPE" == "patch" ]; then
              # Bug fixes not affecting the API
              NEXT="$MAJOR.$MINOR.$((PATCH+1))"
            else
              NEXT=$VERSION
            fi
          fi

          if [[ "$VERSION" != "$NEXT" ]]; then
            # Create body of Pull Request
            echo "### History" >> subjects.txt
            echo "" >> subjects.txt
            echo "Next: $NEXT ($METHOD)" >> subjects.txt
            echo "Latest: $VERSION" >> subjects.txt
            echo "### Release" >> subjects.txt
            # Reverses all lines in subjects.txt
            tac subjects.txt > temp.txt
            BODY=$(cat temp.txt)

            # Clean up files
            rm log.txt
            rm subjects.txt
            rm types.txt
            rm temp.txt

            # Bump version in pyproject.toml
            sed -i "s/version = \"$VERSION\"/version = \"$NEXT\"/g" pyproject.toml

            # Set up git config for github-actions bot
            git config --global user.email "github-actions[bot]@users.noreply.github.com"
            git config --global user.name "github-actions[bot]"

            # Set author to the user running workflow
            AUTHOR="${{ github.actor }} <${{ github.actor }}@users.noreply.github.com>"

            # Checkout new branch
            git checkout -B "release-$NEXT"

            # Commit pyproject.toml
            git add pyproject.toml
            git commit -m "release: bump poetry version in pyproject.toml" --author="$AUTHOR"

            # Push branch
            git push --set-upstream origin "release-$NEXT" --atomic

            # Open Pull Request
            gh pr create --base "main" --title "release: increment version from $VERSION to $NEXT" --body "$BODY"
          fi