build-and-publish.yml

name: Docker Image
on:
  push:
    tags:
      - '**'
    branches:
      - main
  pull_request:
    paths:
      - .github/workflows/jaeger-dockerimage.yml
      - Dockerfile
      - protoc-wrapper

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
    - 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
      with:
        install: true

    - name: Extract tags/labels from Git
      id: docker_meta
      uses: docker/metadata-action@v5
      with:
        images: jaegertracing/protobuf
        # The 'tags:' section defines how the Docker image will be tagged:
        #   - pushes to main branch will be published as 'latest'
        #   - pushes tagged with semver will be published as that version (without 'v')
        #   - other tags can be used as is
        # Documentation: https://github.com/docker/metadata-action#tags-input
        tags: |
          type=raw,value=latest,enable=${{ github.ref == 'refs/heads/main' }}
          type=semver,pattern={{version}}
          type=ref,event=tag

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

    - name: Build and maybe push Docker image
      uses: docker/build-push-action@v5
      with:
        push: ${{ github.ref == 'refs/heads/main' || startsWith(github.ref, 'refs/tags/') }}
        tags: ${{ steps.docker_meta.outputs.tags }}
        labels: ${{ steps.docker_meta.outputs.labels }}
        cache-from: type=gha
        cache-to: type=gha,mode=max
        platforms: linux/amd64,linux/arm64