docker-build-publish.yml

name: Docker Build & Publish

on:
  push:
    branches: ["main"]
    # Publish semver tags as releases.
    tags: ["v*.*.*"]
  pull_request:
    branches: ["main"]

env:
  REGISTRY: ghcr.io
  IMAGE_NAME: ${{ github.repository }}
  OCI_IMAGE_NAME: ""
  OCI_PUSH: ${{ vars.OCI_PUSH }}

jobs:
  build:
    name: Build OCI Images
    runs-on: ${{ matrix.os }}
    strategy:
      fail-fast: false
      matrix:
        include:
          - os: ubuntu-24.04
            arch: amd64
            platform: linux/amd64
          - os: ubuntu-24.04-arm
            arch: arm64
            platform: linux/arm64
    steps:
      - name: Prepare
        run: |
          platform=${{ matrix.platform }}
          echo "PLATFORM_PAIR=${platform//\//-}" >> $GITHUB_ENV

      - name: Set correct OCI image name
        id: ociImageName
        run: echo "::set-output name=lowerCaseValue::${OCI_IMAGE_NAME,,}"
        env:
          OCI_IMAGE_NAME: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}

      # Checkout the repo
      - name: Checkout repository
        uses: actions/checkout@v7
        with:
          fetch-depth: 0

      - name: Show git version info
        run: |
          echo "git describe (dirty): $(git describe --dirty --always --tags)"
          echo "git describe --tags: $(git describe --tags `git rev-list --tags --max-count=1`)"
          echo "git tag: $(git tag --sort=-committerdate | head -n 1)"
          echo "github_ref: $GITHUB_REF"
          echo "github_head_sha: ${{ github.event.pull_request.head.sha }}"
          git tag -l

      - name: Determine git current SHA and latest tag
        id: git-version
        run: |
          if [[ "$GITHUB_REF" == refs/tags/* ]]; then
            GIT_TAG=${GITHUB_REF#refs/tags/}
          elif [[ "$GITHUB_REF" == refs/pull/* ]]; then
            PR_NUMBER=$(echo "$GITHUB_REF" | awk -F'/' '{print $3}')
            GIT_TAG="pr-${PR_NUMBER}"
          else
            GIT_TAG="dev"
          fi
          echo "GIT_TAG=$GIT_TAG" >> "$GITHUB_OUTPUT"

          GIT_SHA=$(git rev-parse --short HEAD)
          echo "GIT_SHA=$GIT_SHA" >> $GITHUB_OUTPUT

          echo "GIT_TAG=$GIT_TAG"
          echo "GIT_SHA=$GIT_SHA"

      # Set up Docker Buildx
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4

      # Extract metadata (tags, labels) for Docker
      - name: Extract Docker metadata (release)
        id: meta
        uses: docker/metadata-action@v6
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}

      # Login into GitHub Container Registry (only if OCI_PUSH is true and not run by Dependabot)
      - name: Log into registry ${{ env.REGISTRY }}
        uses: docker/login-action@v4
        if: env.OCI_PUSH == 'true' && github.actor != 'dependabot[bot]'
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push by digest
        id: build
        uses: docker/build-push-action@v7
        with:
          push: ${{ env.OCI_PUSH == 'true' && github.actor != 'dependabot[bot]' }}
          platforms: ${{ matrix.platform }}
          labels: ${{ steps.meta.outputs.labels }}
          annotations: ${{ steps.meta.outputs.annotations }}
          outputs: type=image,"name=${{ steps.ociImageName.outputs.lowerCaseValue }}",push-by-digest=true,name-canonical=true
          build-args: |
            GIT_TAG=${{ steps.git-version.outputs.GIT_TAG }}
            GIT_SHA=${{ steps.git-version.outputs.GIT_SHA }}

      - name: Export digest
        run: |
          mkdir -p ${{ runner.temp }}/digests
          digest="${{ steps.build.outputs.digest }}"
          touch "${{ runner.temp }}/digests/${digest#sha256:}"

      - name: Upload digest
        uses: actions/upload-artifact@v7
        if: env.OCI_PUSH == 'true' && github.actor != 'dependabot[bot]'
        with:
          name: digests-${{ env.PLATFORM_PAIR }}
          path: ${{ runner.temp }}/digests/*
          if-no-files-found: error
          retention-days: 1

  merge:
    runs-on: ubuntu-latest
    if: vars.OCI_PUSH == 'true' && github.actor != 'dependabot[bot]'
    needs:
      - build
    concurrency:
      group: ${{ github.ref }}
      cancel-in-progress: false
    steps:
      - name: Set correct OCI image name
        id: ociImageName
        run: |
          echo "lowerCaseValue=${OCI_IMAGE_NAME,,}" >> $GITHUB_OUTPUT
        env:
          OCI_IMAGE_NAME: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}

      - name: Download digests
        uses: actions/download-artifact@v8
        with:
          path: ${{ runner.temp }}/digests
          pattern: digests-*
          merge-multiple: true

      - name: Log into registry ${{ env.REGISTRY }}
        uses: docker/login-action@v4
        if: github.actor != 'dependabot[bot]'
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4

      - name: Docker meta
        id: meta
        uses: docker/metadata-action@v6
        with:
          images: |
            ${{ steps.ociImageName.outputs.lowerCaseValue }}
          tags: |
            type=ref,event=pr
            type=semver,pattern={{version}}
            type=raw,value=dev,enable={{is_default_branch}}

      - name: Create manifest list and push
        working-directory: ${{ runner.temp }}/digests
        run: |
          docker buildx imagetools create $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
            $(printf '${{ steps.ociImageName.outputs.lowerCaseValue }}@sha256:%s ' *)

      - name: Inspect image
        run: |
          docker buildx imagetools inspect ${{ steps.ociImageName.outputs.lowerCaseValue }}:${{ steps.meta.outputs.version }}