name: Docker Build

on:
  workflow_dispatch:
  pull_request:

env:
  REGISTRY_IMAGE: stalwartlabs/mail-server

jobs:
  build_docker:
    name: Build Docker image for ${{ matrix.platform }}
    runs-on: ubuntu-latest
    if: '!cancelled()'
    strategy:
      fail-fast: false
      matrix:
        platform:
          - linux/amd64
          - linux/arm64
    steps:
      -
        name: Prepare
        run: |
          platform=${{ matrix.platform }}
          echo "PLATFORM_PAIR=${platform//\//-}" >> $GITHUB_ENV
      -
        name: Checkout
        uses: actions/checkout@v3
      -
        name: Docker meta
        id: meta
        uses: docker/metadata-action@v4
        with:
          images: ${{ env.REGISTRY_IMAGE }}
          tags: |
            type=schedule
            type=ref,event=branch
            type=ref,event=pr
            type=semver,pattern={{version}}
            type=semver,pattern={{major}}.{{minor}}
            type=semver,pattern={{major}}
            type=sha
      -
        name: Set up QEMU
        uses: docker/setup-qemu-action@v2
      -
        name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v2
      -
        name: Login to Docker Hub
        uses: docker/login-action@v2
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}
      -
        name: Build and push by digest
        id: build
        uses: docker/build-push-action@v4
        with:
          context: .
          platforms: ${{ matrix.platform }}
          labels: ${{ steps.meta.outputs.labels }}
          outputs: type=image,name=${{ env.REGISTRY_IMAGE }},push-by-digest=true,name-canonical=true,push=true
          #cache-from: type=registry,ref=${{ env.REGISTRY_IMAGE }}:buildcache-${{ env.PLATFORM_PAIR }}
          #cache-to: type=registry,ref=s${{ env.REGISTRY_IMAGE }}:buildcache-${{ env.PLATFORM_PAIR }},mode=max
          cache-from: type=gha,scope=build-${{ env.PLATFORM_PAIR }}
          cache-to: type=gha,scope=build-${{ env.PLATFORM_PAIR }}
      -
        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@v3
        with:
          name: digests
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1
  
  merge_docker:
    name: Merge and push Docker manifest
    runs-on: ubuntu-latest
    needs:
      - build_docker
    steps:
      -
        name: Download digests
        uses: actions/download-artifact@v3
        with:
          name: digests
          path: /tmp/digests
      -
        name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v2
      -
        name: Docker meta
        id: meta
        uses: docker/metadata-action@v4
        with:
          images: ${{ env.REGISTRY_IMAGE }}
      -
        name: Login to Docker Hub
        uses: docker/login-action@v2
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}
      -
        name: Create manifest list and push
        working-directory: /tmp/digests
        run: |
          docker buildx imagetools create $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
            $(printf '${{ env.REGISTRY_IMAGE }}@sha256:%s ' *)
      -
        name: Inspect image
        run: |
          docker buildx imagetools inspect ${{ env.REGISTRY_IMAGE }}:${{ steps.meta.outputs.version }}