backend-docker.yml

name: Docker build

on:
  push:
    paths:
      - .github/workflows/backend-docker.yml
      - "apps/backend/**"
      - build.gradle.kts
      - settings.gradle.kts
  pull_request:
    types: [opened, synchronize]
    paths:
      - .github/workflows/backend-docker.yml
      - "apps/backend/**"
      - build.gradle.kts
      - settings.gradle.kts

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

permissions:
  contents: read
  packages: write

env:
  REGISTRY: ghcr.io
  IMAGE_NAME: solitar-dev/backend
  GHCR_IMAGE: ghcr.io/solitar-dev/backend

jobs:
  build:
    strategy:
      matrix:
        include:
          - platform: linux/amd64
            runs-on: ubuntu-latest

          - platform: linux/arm64
            runs-on: ubuntu-24.04-arm

    runs-on: ${{ matrix.runs-on }}
    name: Build Docker image for ${{ matrix.platform }}

    steps:
      - name: Prepare environment for current platform
        id: prepare
        run: |
          platform=${{ matrix.platform }}
          echo "PLATFORM_PAIR=${platform//\//-}" >> $GITHUB_ENV

      - uses: actions/checkout@v6

      - name: Setup Docker Buildx
        uses: docker/setup-buildx-action@v3
        with:
          platforms: ${{ matrix.platform }}

      - name: Generate Docker image metadata
        id: docker_meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.GHCR_IMAGE }}
          labels: |
            org.opencontainers.image.title=solitar
            org.opencontainers.image.description=Solitar API
            org.opencontainers.image.licenses=MIT
          annotations: |
            org.opencontainers.image.title=solitar
            org.opencontainers.image.description=Solitar API
            org.opencontainers.image.licenses=MIT

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

      - name: Build and push
        id: build
        uses: docker/build-push-action@v6
        with:
          file: ./apps/backend/Dockerfile
          labels: ${{ steps.docker_meta.outputs.labels }}
          annotations: ${{ steps.docker_meta.outputs.annotations }}
          outputs: type=image,name=${{ env.GHCR_IMAGE }},push-by-digest=true,name-canonical=true,push=${{ github.event_name != 'pull_request' }},oci-mediatypes=true
          cache-from: type=gha,scope=${{ github.repository }}-${{ github.ref_name }}-${{ matrix.platform }}
          cache-to: type=gha,scope=${{ github.repository }}-${{ github.ref_name }}-${{ matrix.platform }}

      - 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@v7
        with:
          name: digests-${{ env.PLATFORM_PAIR }}
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1

  merge:
    name: Merge Docker manifests
    runs-on: ubuntu-latest

    needs:
      - build

    steps:
      - name: Download digests
        uses: actions/download-artifact@v8
        with:
          path: /tmp/digests
          pattern: digests-*
          merge-multiple: true

      - name: Docker meta
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.GHCR_IMAGE }}
          annotations: |
            type=org.opencontainers.image.description,value=${{ github.event.repository.description || 'No description provided' }}
          tags: |
            type=ref,event=branch
            type=semver,pattern={{version}}

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

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

      - name: Get execution timestamp with RFC3339 format
        id: timestamp
        run: |
          echo "timestamp=$(date -u +"%Y-%m-%dT%H:%M:%SZ")" >> $GITHUB_OUTPUT

      - name: Create manifest list and push
        working-directory: /tmp/digests
        id: manifest-annotate
        continue-on-error: true
        run: |
          docker buildx imagetools create \
            $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
            --annotation='index:org.opencontainers.image.description=${{ github.event.repository.description }}' \
            --annotation='index:org.opencontainers.image.created=${{ steps.timestamp.outputs.timestamp }}' \
            --annotation='index:org.opencontainers.image.url=${{ github.event.repository.url }}' \
            --annotation='index:org.opencontainers.image.source=${{ github.event.repository.url }}' \
            $(printf '${{ env.GHCR_IMAGE }}@sha256:%s ' *)

      - name: Create manifest list and push without annotations
        if: steps.manifest-annotate.outcome == 'failure'
        working-directory: /tmp/digests
        run: |
          docker buildx imagetools create  $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
            $(printf '${{ env.GHCR_IMAGE }}@sha256:%s ' *)

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