misskey/.github/workflows/docker-develop.yml

name: Publish Docker image (develop)

on:
  push:
    branches:
      - develop
  workflow_dispatch:

env:
  REGISTRY_IMAGE: misskey/misskey

jobs:
  # see https://docs.docker.com/build/ci/github-actions/multi-platform/#distribute-build-across-multiple-runners
  build:
    name: Build
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        platform:
          - linux/amd64
          - linux/arm64
    if: github.repository == 'misskey-dev/misskey'
    steps:
      - name: Prepare
        run: |
          platform=${{ matrix.platform }}
          echo "PLATFORM_PAIR=${platform//\//-}" >> $GITHUB_ENV          
      - name: Check out the repo
        uses: actions/checkout@v4.1.1
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3
      - name: Log in to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_PASSWORD }}
      - name: Build and push by digest
        id: build
        uses: docker/build-push-action@v5
        with:
          context: .
          push: true
          platforms: ${{ matrix.platform }}
          provenance: false
          tags: ${{ env.REGISTRY_IMAGE }}:develop
          labels: develop
          cache-from: type=gha
          cache-to: type=gha,mode=max
          outputs: type=image,name=${{ env.REGISTRY_IMAGE }},push-by-digest=true,name-canonical=true,push=true
      - 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@v4
        with:
          name: digests-${{ env.PLATFORM_PAIR }}
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1

  merge:
    runs-on: ubuntu-latest
    needs:
      - build
    steps:
      - name: Download digests
        uses: actions/download-artifact@v4
        with:
          path: /tmp/digests
          pattern: digests-*
          merge-multiple: true
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3
      - name: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_PASSWORD }}
      - name: Create manifest list and push
        working-directory: /tmp/digests
        run: |
          docker buildx imagetools create --tag ${{ env.REGISTRY_IMAGE }}:develop \
            $(printf '${{ env.REGISTRY_IMAGE }}@sha256:%s ' *)          
      - name: Inspect image
        run: |
          docker buildx imagetools inspect ${{ env.REGISTRY_IMAGE }}:develop