docker-images.yml

# Based on 
#  - https://docs.github.com/en/actions/use-cases-and-examples/publishing-packages/publishing-docker-images
#  - https://docs.docker.com/build/ci/github-actions/multi-platform/#distribute-build-across-multiple-runners

name: Create and publish Docker images

on:
  push:
    branches:
      - 'main'
    tags:
      - 'v*'
  pull_request:
    paths:
      - .github/workflows/docker-images.yml
      - Dockerfile
## disabling for most PRs, too many builds
#    branches:
#      - 'main'

env:
  REGISTRY: ghcr.io
  IMAGE_NAME: ${{ github.repository }}

jobs:
  build:
    runs-on: ${{ matrix.os }}
    strategy:
      matrix:
        target: [web, index, mongo]
        platform:
          - linux/amd64
          - linux/arm64
        include:
          - platform: linux/amd64
            os: ubuntu-latest
          - platform: linux/arm64
            os: ubuntu-24.04-arm

    permissions:
      contents: read
      packages: write
      id-token: write

    steps:
      - name: Delete huge unnecessary tools folder
        run: |
          rm -rf /opt/hostedtoolcache
          cd /opt
          find . -maxdepth 1 -mindepth 1 '!' -path ./containerd '!' -path ./actionarchivecache '!' -path ./runner '!' -path ./runner-cache -exec rm -rf '{}' ';'

      - name: Checkout repository
        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683

      - name: Log in to the Container registry
        uses: docker/login-action@65b78e6e13532edd9afa3aa52ac7964289d1a9c1
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@6524bf65af31da8d45b59e8c27de4bd072b392f5

      - name: Prepare
        run: |
          platform=${{ matrix.platform }}
          echo "PLATFORM_PAIR=${platform//\//-}" >> $GITHUB_ENV

      - name: Extract metadata (tags, labels) for Docker
        id: meta
        uses: docker/metadata-action@9ec57ed1fcdbf14dcef7dfbe97b2010124a938b7
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}

      - name: Build and push by digest
        id: build
        uses: docker/build-push-action@f2a1d5e99d037542a71f64918e516c093c6f3fc4
        with:
          context: .
          platforms: ${{ matrix.platform }}
          labels: ${{ steps.meta.outputs.labels }}
          target: ${{ matrix.target }}
          outputs: type=image,"name=${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}",push-by-digest=true,name-canonical=true,push=true
          cache-from: type=gha
          cache-to: type=gha,mode=max
          # don't push on PRs
          push: ${{ ! startsWith(github.ref, 'refs/pull/') }}

      - 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@65c4c4a1ddee5b72f698fdd19549f0f0fb45cf08
        with:
          name: digests-${{ matrix.target }}-${{ env.PLATFORM_PAIR }}
          path: ${{ runner.temp }}/digests/*
          if-no-files-found: error
          retention-days: 1

  merge:
    runs-on: ubuntu-latest
    # avoid tagging on PRs
    if: ${{ ! startsWith(github.ref, 'refs/pull/') }}
    needs:
      - build

    strategy:
      matrix:
        target: [web, index, mongo]

    permissions:
      contents: read
      packages: write
      attestations: write
      id-token: write

    steps:
      - name: Download digests
        uses: actions/download-artifact@fa0a91b85d4f404e444e00e005971372dc801d16
        with:
          path: ${{ runner.temp }}/digests
          pattern: digests-${{ matrix.target }}-*
          merge-multiple: true

      - name: Log in to the Container registry
        uses: docker/login-action@65b78e6e13532edd9afa3aa52ac7964289d1a9c1
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@6524bf65af31da8d45b59e8c27de4bd072b392f5

      - name: Extract metadata (tags, labels) for Docker
        id: meta
        uses: docker/metadata-action@9ec57ed1fcdbf14dcef7dfbe97b2010124a938b7
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          tags: |
            type=ref,event=branch,prefix=${{ matrix.target }}-
            type=ref,event=pr,prefix=${{ matrix.target }}-pr-
            type=semver,prefix=${{ matrix.target }}-,pattern={{version}}

      - 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.REGISTRY }}/${{ env.IMAGE_NAME }}@sha256:%s ' *)

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

#      - name: Generate artifact attestation
#        uses: actions/attest-build-provenance@v2
#        with:
#          subject-name: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
#          subject-digest: ${{ steps.build.outputs.digest }}
#          push-to-registry: true