container.yml

name: Container image

on:
  push:
    branches:
      - 'master'
    tags:
      - 'v*'
  pull_request:
  workflow_dispatch:

jobs:
  build:
    name: Build container image
    runs-on: ubuntu-latest
    strategy:
      matrix:
        platform: [linux/amd64, linux/386, linux/arm64, linux/arm/v6, linux/arm/v7]
    steps:
      - name: Checkout repository
        uses: actions/checkout@v4

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

      - name: Cache wheels
        uses: actions/cache@v4
        with:
          path: ${{ github.workspace }}/wheels
          key: wheels-${{ env.PLATFORM }}-${{ github.run_id }}
          restore-keys: |
            wheels-${{ env.PLATFORM }}-

      - name: List wheels
        run: ls -lR ${{ github.workspace }}/wheels || true

      - name: Setup QEMU
        uses: docker/setup-qemu-action@v3

      - name: Setup Buildx
        uses: docker/setup-buildx-action@v3

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

      - name: Calculate container metadata
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ghcr.io/${{ github.repository }}

      - name: Build stage
        id: build
        uses: docker/build-push-action@v6
        with:
          context: .
          platforms: ${{ matrix.platform }}
          provenance: false
          labels: ${{ steps.meta.outputs.labels }}
          outputs: type=local,dest=/tmp/build-output
          cache-to: type=local,dest=/tmp/build-cache,mode=max
          target: build

      - name: Final stage and push by digest
        id: final
        uses: docker/build-push-action@v6
        with:
          context: .
          platforms: ${{ matrix.platform }}
          provenance: false
          labels: ${{ steps.meta.outputs.labels }}
          outputs: type=image,name=ghcr.io/${{ github.repository }},push-by-digest=true,name-canonical=true,push=${{ github.event_name != 'pull_request' && 'true' || 'false' }}
          cache-from: type=local,src=/tmp/build-cache

      - name: Export digest
        if: ${{ github.event_name != 'pull_request' }}
        run: |
          mkdir -p /tmp/digests
          digest="${{ steps.final.outputs.digest }}"
          touch "/tmp/digests/${digest#sha256:}"

      - name: Upload digest
        if: ${{ github.event_name != 'pull_request' }}
        uses: actions/upload-artifact@v4
        with:
          name: digests-${{ env.PLATFORM }}
          path: /tmp/digests/*
          if-no-files-found: error
          retention-days: 1

      - name: Move and list wheels
        run: |
          mv -f /tmp/build-output/root/.cache/pip/wheels ${{ github.workspace }}/ || true
          ls -lR ${{ github.workspace }}/wheels || true

  merge:
    name: Publish multi-platform image
    if: ${{ github.event_name != 'pull_request' }}
    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: Calculate container metadata
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ghcr.io/${{ github.repository }}

      - name: Setup Buildx
        uses: docker/setup-buildx-action@v2

      - name: Login to GitHub Container Registry
        uses: docker/login-action@v2
        with:
          registry: ghcr.io
          username: ${{ github.repository_owner }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Create and push manifest
        working-directory: /tmp/digests
        run: |
          docker buildx imagetools create $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
            $(printf 'ghcr.io/${{ github.repository }}@sha256:%s ' *)

      - name: Inspect container image
        run: |
          docker buildx imagetools inspect ghcr.io/${{ github.repository }}:${{ steps.meta.outputs.version }}