# GitHub actions workflow which builds the release artifacts.

name: Build release artifacts

on:
  # we build on PRs and develop to (hopefully) get early warning
  # of things breaking (but only build one set of debs)
  pull_request:
  push:
    branches: ["develop", "release-*"]

    # we do the full build on tags.
    tags: ["v*"]

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
  
permissions:
  contents: write

jobs:
  get-distros:
    name: "Calculate list of debian distros"
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: actions/setup-python@v2
      - id: set-distros
        run: |
          # if we're running from a tag, get the full list of distros; otherwise just use debian:sid
          dists='["debian:sid"]'
          if [[ $GITHUB_REF == refs/tags/* ]]; then
              dists=$(scripts-dev/build_debian_packages.py --show-dists-json)
          fi
          echo "::set-output name=distros::$dists"
    # map the step outputs to job outputs
    outputs:
      distros: ${{ steps.set-distros.outputs.distros }}

  # now build the packages with a matrix build.
  build-debs:
    needs: get-distros
    name: "Build .deb packages"
    runs-on: ubuntu-latest
    strategy:
      matrix:
        distro: ${{ fromJson(needs.get-distros.outputs.distros) }}

    steps:
      - name: Checkout
        uses: actions/checkout@v2
        with:
          path: src

      - name: Set up Docker Buildx
        id: buildx
        uses: docker/setup-buildx-action@v1
        with:
          install: true

      - name: Set up docker layer caching
        uses: actions/cache@v2
        with:
          path: /tmp/.buildx-cache
          key: ${{ runner.os }}-buildx-${{ github.sha }}
          restore-keys: |
            ${{ runner.os }}-buildx-

      - name: Set up python
        uses: actions/setup-python@v2

      - name: Build the packages
        # see https://github.com/docker/build-push-action/issues/252
        # for the cache magic here
        run: |
          ./src/scripts-dev/build_debian_packages.py \
            --docker-build-arg=--cache-from=type=local,src=/tmp/.buildx-cache \
            --docker-build-arg=--cache-to=type=local,mode=max,dest=/tmp/.buildx-cache-new \
            --docker-build-arg=--progress=plain \
            --docker-build-arg=--load \
            "${{ matrix.distro }}"
          rm -rf /tmp/.buildx-cache
          mv /tmp/.buildx-cache-new /tmp/.buildx-cache

      - name: Upload debs as artifacts
        uses: actions/upload-artifact@v2
        with:
          name: debs
          path: debs/*

  build-sdist:
    name: "Build pypi distribution files"
    uses: "matrix-org/backend-meta/.github/workflows/packaging.yml@v1"

  # if it's a tag, create a release and attach the artifacts to it
  attach-assets:
    name: "Attach assets to release"
    if: ${{ !failure() && !cancelled() && startsWith(github.ref, 'refs/tags/') }}
    needs:
      - build-debs
      - build-sdist
    runs-on: ubuntu-latest
    steps:
      - name: Download all workflow run artifacts
        uses: actions/download-artifact@v2
      - name: Build a tarball for the debs
        run: tar -cvJf debs.tar.xz debs
      - name: Attach to release
        uses: softprops/action-gh-release@a929a66f232c1b11af63782948aa2210f981808a  # PR#109
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        with:
          files: |
            python-dist/*
            debs.tar.xz
          # if it's not already published, keep the release as a draft.
          draft: true
          # mark it as a prerelease if the tag contains 'rc'.
          prerelease: ${{ contains(github.ref, 'rc') }}