project-nomad/.github/workflows/build-primary-image.yml

name: Build Primary Docker Image

on:
  release:
    types: [published]
  workflow_dispatch:
    inputs:
      version:
        description: 'Semantic version to label the Docker image under (no "v" prefix, e.g. "1.2.3")'
        required: true
        type: string
      tag_latest:
        description: 'Also tag this image as :latest? (Keep false for RC and beta releases)'
        required: false
        type: boolean
        default: false

jobs:
  setup:
    name: Resolve version and check authorization
    runs-on: ubuntu-latest
    outputs:
      isAuthorized: ${{ steps.check-auth.outputs.is_authorized }}
      version: ${{ steps.vars.outputs.version }}
      tag_latest: ${{ steps.vars.outputs.tag_latest }}
    steps:
      - name: check-auth
        id: check-auth
        run: |
          if [ "${{ github.event_name }}" = "release" ]; then
            echo "is_authorized=true" >> $GITHUB_OUTPUT
          else
            echo "is_authorized=${{ contains(secrets.DEPLOYMENT_AUTHORIZED_USERS, github.triggering_actor) }}" >> $GITHUB_OUTPUT
          fi          
      - name: Resolve version and tag_latest
        id: vars
        run: |
          if [ "${{ github.event_name }}" = "release" ]; then
            VERSION="${{ github.event.release.tag_name }}"
            VERSION="${VERSION#v}"
            TAG_LATEST=${{ !github.event.release.prerelease }}
          else
            VERSION="${{ inputs.version }}"
            TAG_LATEST=${{ inputs.tag_latest }}
          fi
          echo "version=$VERSION" >> $GITHUB_OUTPUT
          echo "tag_latest=$TAG_LATEST" >> $GITHUB_OUTPUT          

  build:
    name: Build primary image (${{ matrix.platform }})
    needs: setup
    if: needs.setup.outputs.isAuthorized == 'true'
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
    strategy:
      fail-fast: false
      matrix:
        platform: [linux/amd64, linux/arm64]
    steps:
      - name: Checkout code
        uses: actions/checkout@v4
      - name: Set up QEMU
        uses: docker/setup-qemu-action@v3
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3
      - name: Log in to GitHub Container Registry
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}
      - name: Build and push by digest
        id: build
        uses: docker/build-push-action@v6
        with:
          platforms: ${{ matrix.platform }}
          outputs: type=image,name=ghcr.io/${{ github.repository_owner }}/project-nomad,push-by-digest=true,name-canonical=true,push=true
          build-args: |
            VERSION=${{ needs.setup.outputs.version }}
            BUILD_DATE=${{ github.event.release.created_at }}
            VCS_REF=${{ github.sha }}            
      - name: Export digest
        run: |
          mkdir -p /tmp/digests
          digest="${{ steps.build.outputs.digest }}"
          touch "/tmp/digests/${digest#sha256:}"          
      - name: Upload digest
        uses: actions/upload-artifact@v4
        with:
          name: digests-${{ matrix.platform == 'linux/amd64' && 'amd64' || 'arm64' }}
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1

  merge:
    name: Create and push multi-arch manifest
    needs: [setup, build]
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
    steps:
      - name: Download digests
        uses: actions/download-artifact@v4
        with:
          path: /tmp/digests
          pattern: digests-*
          merge-multiple: true
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3
      - name: Log in to GitHub Container Registry
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}
      - name: Create manifest list and push
        run: |
          VERSION="${{ needs.setup.outputs.version }}"
          TAGS="-t ghcr.io/${{ github.repository_owner }}/project-nomad:${VERSION}"
          TAGS="$TAGS -t ghcr.io/${{ github.repository_owner }}/project-nomad:v${VERSION}"
          if [ "${{ needs.setup.outputs.tag_latest }}" = "true" ]; then
            TAGS="$TAGS -t ghcr.io/${{ github.repository_owner }}/project-nomad:latest"
          fi
          docker buildx imagetools create $TAGS \
            $(printf 'ghcr.io/${{ github.repository_owner }}/project-nomad@sha256:%s ' *)          
        working-directory: /tmp/digests
      - name: Inspect image
        run: |
          docker buildx imagetools inspect ghcr.io/${{ github.repository_owner }}/project-nomad:${{ needs.setup.outputs.version }}