release.yml

# Creates a GitHub release whenever a version tag is pushed, using the
# corresponding section of CHANGELOG.md as release notes.
on:
  push:
    tags:
      - 'v*'
  workflow_dispatch:
    inputs:
      tag:
        description: 'Existing version tag to (re-)generate the release for, e.g. v1.4.1'
        required: true

name: release

jobs:
  release:
    runs-on: ubuntu-latest

    permissions:
      contents: write

    steps:
      - name: Determine tag
        id: tag
        shell: bash
        run: |
          set -euo pipefail
          TAG="${{ github.event.inputs.tag || github.ref_name }}"
          echo "tag=${TAG}" >> "$GITHUB_OUTPUT"
          echo "version=${TAG#v}" >> "$GITHUB_OUTPUT"

      - uses: actions/checkout@v4
        with:
          ref: ${{ steps.tag.outputs.tag }}

      - name: Extract release notes from CHANGELOG.md
        id: notes
        shell: bash
        run: |
          set -euo pipefail
          VERSION="${{ steps.tag.outputs.version }}"

          # Print everything between the level 2 CHANGELOG.md heading that
          # mentions this version and the next level 1 or 2 heading, then
          # strip the blank lines at both ends.
          awk -v ver="$VERSION" '
            /^##? / {
              if (found) exit
              line = $0
              gsub(/[^0-9A-Za-z.]+/, " ", line)
              split(line, tok, " ")
              for (i in tok) if (tok[i] == ver) found = 1
              next
            }
            found { print }
          ' CHANGELOG.md | sed -e '/./,$!d' | tac | sed -e '/./,$!d' | tac > release-notes.md

          if [ ! -s release-notes.md ]; then
            echo "::error::No CHANGELOG.md section found for version ${VERSION}."
            exit 1
          fi

          echo "Release notes for ${VERSION}:"
          cat release-notes.md

          PACKAGE_VERSION="$(grep -m1 '^version[[:space:]]*=' pyproject.toml | sed -e 's/^version[[:space:]]*=[[:space:]]*"\(.*\)".*/\1/')"
          if [ "$PACKAGE_VERSION" != "$VERSION" ]; then
            echo "::warning::Tag version ${VERSION} does not match pyproject.toml version ${PACKAGE_VERSION}."
          fi

          # x.y.z is a regular (PyPI) release, everything else a pre-release
          if echo "$VERSION" | grep -qE '^[0-9]+\.[0-9]+\.[0-9]+$'; then
            echo "title=PyPi release v${VERSION}" >> "$GITHUB_OUTPUT"
            echo "prerelease=" >> "$GITHUB_OUTPUT"
          else
            echo "title=PythonKorAPClient v${VERSION}" >> "$GITHUB_OUTPUT"
            echo "prerelease=--prerelease" >> "$GITHUB_OUTPUT"
          fi

      - name: Create or update the release
        shell: bash
        env:
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        run: |
          set -euo pipefail
          TAG="${{ steps.tag.outputs.tag }}"

          if gh release view "$TAG" --repo "$GITHUB_REPOSITORY" > /dev/null 2>&1; then
            echo "Release ${TAG} already exists, updating it."
            gh release edit "$TAG" \
              --repo "$GITHUB_REPOSITORY" \
              --title "${{ steps.notes.outputs.title }}" \
              --notes-file release-notes.md
          else
            gh release create "$TAG" \
              --repo "$GITHUB_REPOSITORY" \
              --title "${{ steps.notes.outputs.title }}" \
              --notes-file release-notes.md \
              ${{ steps.notes.outputs.prerelease }}
          fi