Github Action for Docker Build and Push to Google Artifact Registry

github-docker-build-and-push.yml

name: CI

on:
  push:
    branches:
      - main
  pull_request:

env:
  # Github Container registry
  REGISTRY: us-docker.pkg.dev
  REGISTRY_PATH: ${{ secrets.GCP_PROJECT_ID }}/YOUR_GAR_REGISTRY_NAME
  GCP_REGION: us-central1
  SERVICE_NAME: YOUR_SERVICE_NAME

jobs:
  build:

    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write
      # This is used to complete the identity challenge
      # with sigstore/fulcio when running outside of PRs.
      id-token: write

    steps:
      - name: Checkout repository
        uses: actions/checkout@v2

      - name: Setup Docker buildx
        uses: docker/setup-buildx-action@v1

      # Login against a Docker registry except on PR
      - name: Log into registry Google Artifact Registry
        if: github.event_name != 'pull_request'
        uses: docker/login-action@v1
        with:
          registry: ${{ env.REGISTRY }}
          username: _json_key_base64
          password: ${{ secrets.GCP_SA_KEY }}

      # Extract metadata (tags, labels) for Docker
      # https://github.com/docker/metadata-action
      - name: Extract Docker metadata
        id: meta
        uses: docker/metadata-action@v3
        with:
          images: ${{ env.REGISTRY }}/${{ env.REGISTRY_PATH }}/${{ env.SERVICE_NAME }}

      # Build and push Docker image with Buildx (don't push on PR)
      # https://github.com/docker/build-push-action
      - name: Build and push Docker image
        id: 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 }}

For anyone coming along in 2022+ looking to get Docker builds working with Google Artifact Registry, here's one that will work if you have the appropriate secrets defined in Github Secrets for your repository.

• GCP_PROJECT_ID for your Google Cloud project ID
• GCP_SA_KEY with the base64 encoded service account JSON)