name: Docker
on:
  push:
    branches:
      - 'develop'
    tags:
      - 'v?[0-9]+.[0-9]+.[0-9]+'
jobs:
  docker:
    runs-on: ubuntu-latest
    steps:
      - name: Check out
        uses: actions/checkout@v2
      - name: Docker meta
        id: meta
        uses: docker/metadata-action@v3
        with:
          images: etherpad/etherpad
          tags: |
            type=ref,event=branch
            type=semver,pattern={{version}}
            type=semver,pattern={{major}}.{{minor}}
            type=semver,pattern={{major}}
      - name: Log in to Docker Hub
        if: github.event_name != 'pull_request'
        uses: docker/login-action@v1
        with:
          username: ${{ secrets.DOCKERHUB_USERNAME }}
          password: ${{ secrets.DOCKERHUB_TOKEN }}
      - name: Build and push
        uses: docker/build-push-action@v2
        with:
          context: .
          push: ${{ github.event_name != 'pull_request' }}
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}