github_release_docker.yml

name: Build + Release docker

on:
  push:
    tags:
      - 'v*'
  workflow_dispatch:

jobs:
  build_docker:
    runs-on: ${{ matrix.runs-on }}
    name: Build & publish docker image
    strategy:
      fail-fast: false
      matrix:
        runs-on:
          - ubuntu-24.04
          - ubuntu-24.04-arm
    steps:
      - name: Check out the repo
        uses: actions/checkout@v4
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3
      - name: Docker meta
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ghcr.io/${{ github.repository }}
          flavor: latest=true

      - name: Login to image repository
        if: github.ref_type == 'tag'
        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@48aba3b46d1b1fec4febb7c5d0c644b249a11355
        with:
          context: .
          file: Dockerfile
          # push: ${{ github.ref_type == 'tag' }}
          push: true
          # This is required or a package with unknown architecture will be published too.
          # See https://github.com/docker/build-push-action/issues/820 for further
          # details.
          # TODO - investigate further and see if we can find a solution where we
          # don't have to set this.
          provenance: false
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}
          cache-from: type=gha
          cache-to: type=gha
          outputs: type=image,"name=${{ env.DOCKERHUB_REPO }},${{ env.GHCR_REPO }}",push-by-digest=true,name-canonical=true,push=true
      
      - 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@v4
        with:
          name: digests-${{ env.PLATFORM_PAIR }}
          path: ${{ runner.temp }}/digests/*
          if-no-files-found: error
          retention-days: 1

  merge:
    #if: ${{ github.ref_type == 'tag' }}
    runs-on: ubuntu-latest
    needs:
      - build
    steps:
      - name: Download digests
        uses: actions/download-artifact@v4
        with:
          path: ${{ runner.temp }}/digests
          pattern: digests-*
          merge-multiple: true

      - name: Login to GHCR
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3

      - name: Docker meta
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: |
            ${{ env.DOCKERHUB_REPO }}
            ${{ env.GHCR_REPO }}            
          tags: |
            type=ref,event=branch
            type=ref,event=pr
            type=semver,pattern={{version}}
            type=semver,pattern={{major}}.{{minor}}            

      - 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") \
            $(printf '${{ env.DOCKERHUB_REPO }}@sha256:%s ' *)
          docker buildx imagetools create $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
            $(printf '${{ env.GHCR_REPO }}@sha256:%s ' *)          

      - name: Inspect image
        run: |
          docker buildx imagetools inspect ${{ env.DOCKERHUB_REPO }}:${{ steps.meta.outputs.version }}
          docker buildx imagetools inspect ${{ env.GHCR_REPO }}:${{ steps.meta.outputs.version }}