docker.yml

name: Docker

on:
  workflow_dispatch: # allows to be run manually
  push:
    tags:
      - '*'
  pull_request:
    branches:
      - 'main'

jobs:
  build_and_push:
    name: Build and push Docker image to Docker Hub or GHCR
    runs-on: ubuntu-latest
    env:
      push_to_docker_hub: ${{ secrets.DOCKER_USERNAME != '' && secrets.DOCKER_PASSWORD != '' }}
    steps:
      - name: Checkout
        uses: actions/checkout@v4
        with:
          submodules: true

      - name: Docker meta
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ push_to_docker_hub && 'pretalx/standalone' || format('ghcr.io/{0}', github.repository) }}

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

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

      - name: Login to DockerHub
        if: github.event_name != 'pull_request' && push_to_docker_hub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_PASSWORD }}

      - name: Login to GHCR
        if: github.event_name != 'pull_request' && !push_to_docker_hub
        uses: docker/login-action@v3
        with:
          registry: ghcr.io
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Build and push
        uses: docker/build-push-action@v5
        with:
          context: .
          platforms: linux/amd64,linux/arm64
          push: ${{ github.event_name != 'pull_request' }}
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}