build-container.yml

name: Create and publish a Docker image

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

on:
  push:
    branches: ["main"]
  schedule:
    - cron: "0 2 * * 1"
  workflow_dispatch:

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

jobs:
  build-and-push-image:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
    strategy:
      matrix:
        python-version: ["3.12", "3.13", "3.14"]
        debian-version: ["bookworm", "trixie"]

    steps:
      - name: Checkout repository
        uses: actions/checkout@v6

      - name: Set up QEMU
        uses: docker/setup-qemu-action@v4
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4

      - name: Log in to the Container registry
        uses: docker/login-action@v4
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Prep Image Name
        id: image_tag_lower
        # Black magic fuckery to ensure lowercase string as docker tag
        run: |
          IMAGE_TAG=$(echo "${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}:${{ matrix.python-version }}-${{ matrix.debian-version }}" | awk '{print tolower($0)}')
          echo "IMAGE_TAG=${IMAGE_TAG}" >> $GITHUB_OUTPUT

      - name: Build and push Docker image
        uses: docker/build-push-action@v7
        with:
          context: .
          platforms: linux/amd64,linux/arm64
          push: ${{ github.event_name != 'pull_request' }}
          tags: ${{ steps.image_tag_lower.outputs.IMAGE_TAG }}
          cache-from: type=gha
          cache-to: type=gha,mode=max
          build-args: |
            PYTHONVERSION=${{ matrix.python-version }}
            DEBIANVERSION=${{ matrix.debian-version }}