publish.yml

name: Docker

# This workflow uses actions that are not certified by GitHub.
# They are provided by a third-party and are governed by
# separate terms of service, privacy policy, and support
# documentation.

on:
  schedule:
    - cron: '00 18 * * *'
  push:
    branches:
      - main
      - staging
    # Publish semver tags as releases.
    tags: [ 'v*.*.*' ]
  pull_request:
    branches:
      - main
      - staging
  workflow_dispatch:

env:
  # Use docker.io for Docker Hub if empty
  REGISTRY: ghcr.io
  # github.repository as <account>/<repo>
  IMAGE_NAME: ${{ github.repository }}


jobs:
  build:

    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
      # This is used to complete the identity challenge
      # with sigstore/fulcio when running outside of PRs.
      id-token: write
    strategy:
      matrix:
        ubuntu_version: [focal, noble]
        arch: [s390x, aarch64, x86_64]
        include:
          - arch: s390x
            dockerfile: s390x.Dockerfile
            platform: linux/s390x
          - arch: aarch64
            dockerfile: Dockerfile
            platform: linux/arm64
          - arch: x86_64
            dockerfile: Dockerfile
            platform: linux/amd64

    steps:
      - name: Checkout repository
        uses: actions/checkout@v2

      # Install the cosign tool except on PR
      # https://github.com/sigstore/cosign-installer
      - name: Install cosign
        if: github.event_name != 'pull_request'
        uses: sigstore/cosign-installer@main
      - name: Check cosign install!
        if: github.event_name != 'pull_request'
        run: cosign version

      - name: Set up QEMU
        uses: docker/setup-qemu-action@v2

      - name: Setup Docker buildx
        uses: docker/setup-buildx-action@v2

      # Login against a Docker registry except on PR
      # https://github.com/docker/login-action
      - name: Log into registry ${{ env.REGISTRY }}
        if: github.event_name != 'pull_request'
        uses: docker/login-action@v2
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      # Extract metadata (tags, labels) for Docker
      # https://github.com/docker/metadata-action
      - name: Extract Docker metadata
        id: meta
        uses: docker/metadata-action@v4
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          flavor: |
            latest=auto
            prefix=
            suffix=-${{ matrix.ubuntu_version }}-${{ matrix.arch }}
          tags: |
            # Generate old tag names (e.g main-s390x, main-x86_64...) when building focal
            # branch event
            type=ref,enable=${{ matrix.ubuntu_version == 'focal' }},suffix=-${{ matrix.arch }},event=branch
            # pr event
            type=ref,enable=${{ matrix.ubuntu_version == 'focal' }},prefix=pr-,suffix=-${{ matrix.arch }},event=pr
            # tags for all pr/branches
            type=ref,event=branch,enable=true,priority=600
            type=ref,event=pr,enable=true,prefix=pr-,priority=600          

      # Build and push Docker image with Buildx (don't push on PR)
      # https://github.com/docker/build-push-action
      - name: Build and push Docker image
        id: build-and-push
        uses: docker/build-push-action@v3
        with:
          context: .
          file: ${{ matrix.dockerfile }}
          push: ${{ github.event_name != 'pull_request' }}
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}
          platforms: ${{ matrix.platform }}
          build-args: UBUNTU_VERSION=${{ matrix.ubuntu_version }}

      # Sign the resulting Docker image digest except on PRs.
      # This will only write to the public Rekor transparency log when the Docker
      # repository is public to avoid leaking data.  If you would like to publish
      # transparency data even for private images, pass --force to cosign below.
      # https://github.com/sigstore/cosign
      - name: Sign the published Docker image
        if: ${{ github.event_name != 'pull_request' }}
        env:
          COSIGN_EXPERIMENTAL: "true"
          TAGS: ${{ steps.meta.outputs.tags }}
        # This step uses the identity token to provision an ephemeral certificate
        # against the sigstore community Fulcio instance.
        run: cosign sign --yes ${TAGS}