release.yml

name: Release
on:
  push:
    tags:
      - 'v*.*.*'

jobs:
  release:
    runs-on: ubuntu-latest
    name: Create release and update documentation
    steps:
      - name: Set variables
        id: vars
        run: |
          echo "::set-output name=tag::${GITHUB_REF#refs/*/}"
          echo "::set-output name=target_branch::gh-pages"
          echo "::set-output name=latest_name::latest"

      - name: Check out main branch
        uses: actions/checkout@v2
        with:
          persist-credentials: false

      - name: Check out documentation branch
        uses: actions/checkout@v2
        with:
          ref: ${{ steps.vars.outputs.target_branch }}
          path: ${{ steps.vars.outputs.target_branch }}
          persist-credentials: false

      - name: Cache nimble
        id: cache-nimble
        uses: actions/cache@v2
        with:
          path: ~/.nimble
          key: ${{ runner.os }}-nimble
        if: runner.os != 'Windows'
      - name: Set up Nim
        uses: jiro4989/setup-nim-action@v1
        with:
          nim-version: stable

      - name: Build documentation
        run: nimble docs
      - name: Generate landing page
        run: |
          nim r --hints:off --verbosity:0 $GITHUB_WORKSPACE/docsrc/build_index.nim $GITHUB_WORKSPACE
      - name: Copy documentation
        run: |
          rm -rf ./${{ steps.vars.outputs.latest_name }}
          cp -r $GITHUB_WORKSPACE/docs ./${{ steps.vars.outputs.latest_name }}
          cp -r $GITHUB_WORKSPACE/docs ./${{ steps.vars.outputs.tag }}
        working-directory: ./${{ steps.vars.outputs.target_branch }}

      - name: Deploy documentation
        uses: JamesIves/github-pages-deploy-action@3.7.1
        with:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          BRANCH: ${{ steps.vars.outputs.target_branch }}
          FOLDER: ${{ steps.vars.outputs.target_branch }}
          GIT_CONFIG_NAME: GitHub Action
          GIT_CONFIG_EMAIL: action@github.com
          COMMIT_MESSAGE: 'docs: update documentation to ${{ steps.vars.outputs.tag }}'

      # this is necessary to make retrieving the previous tag possible
      # without it, the previous tag is somehow the same as the current tag
      # this seems to be because of actions/checkout@2
      - name: Clean git tags
        run: git fetch --prune --unshallow --tags --force
      - name: Install fugitive
        run: nimble install -y fugitive

      - name: Create changelog
        id: changelog
        run: |
          TAG=${{ steps.vars.outputs.tag }}
          LAST_TAG=$(git describe --abbrev=0 --tags $(git rev-list --tags --skip=1 --max-count=1))

          echo 'CHANGELOG_BODY<<EOF' >> $GITHUB_ENV
          fugitive changelog --tag:${TAG} --last-tag:${LAST_TAG} --no-anchor --no-title --no-divider >> $GITHUB_ENV
          echo 'EOF' >> $GITHUB_ENV
        env:
          GITHUB_TOKEN: ${{ github.token }}

      - name: Create release
        id: create_release
        uses: actions/create-release@v1
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        with:
          tag_name: ${{ steps.vars.outputs.tag }}
          release_name: ${{ steps.vars.outputs.tag }}
          body: ${{ env.CHANGELOG_BODY }}