publish.yml

name: publish

on:
  schedule:
    - cron: '38 02,08,14,20 * * *'
  push:
    branches: ["main"]
  pull_request:
  workflow_dispatch:

defaults:
  run:
    shell: bash -leoux pipefail {0}

jobs:
  docker:
    runs-on: ubuntu-latest
    concurrency: ci-${{ github.ref }}
    steps:
      - name: Checkout
        uses: actions/checkout@v4
      - name: Set up QEMU
        uses: docker/setup-qemu-action@v3
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v3
      - name: Login into registry
        uses: docker/login-action@v3
        if: github.event_name != 'pull_request'
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}
      - name: Build
        uses: docker/build-push-action@v5
        with:
          context: .
          platforms: linux/amd64
          load: true
          tags: ghcr.io/${{ github.repository }}:test
      - name: Check if changed
        id: checkchanged
        run: |
          mkdir tmp
          cd tmp

          if docker pull --platform linux/amd64 ghcr.io/${{ github.repository }}:latest; then
            img=$(docker create --platform linux/amd64 ghcr.io/${{ github.repository }}:latest)
            docker export $img -o latest.tar
            docker rm $img

            img=$(docker create --platform linux/amd64 ghcr.io/${{ github.repository }}:test)
            docker export $img -o test.tar
            docker rm $img

            mkdir test
            mkdir latest
            tar xf test.tar -C test --exclude={var/{log,cache},lib/apk/db/scripts.tar}
            tar xf latest.tar -C latest --exclude={var/{log,cache},lib/apk/db/scripts.tar}
            if diff -q -r --no-dereference test latest; then
              echo "CHECKEQUALS=true" >> "$GITHUB_OUTPUT"
            fi
          fi
      - name: Build and push
        uses: docker/build-push-action@v5
        if: github.event_name == 'workflow_dispatch' || github.event_name != 'pull_request' && steps.checkchanged.outputs.CHECKEQUALS != 'true'
        with:
          context: .
          platforms: linux/amd64,linux/arm64,linux/arm/v7
          push: ${{ github.event_name != 'pull_request' }}
          tags: |
            ghcr.io/${{ github.repository }}:latest
            ghcr.io/${{ github.repository }}:1