CI/CD with Docker & GitHub Actions

# .github/workflows/docker-build.yml
name: Build and Push Docker Image

on:
  push:
    branches: [main]
  pull_request:
    branches: [main]

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

jobs:
  build:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      packages: write

    steps:
      - name: Checkout code
        uses: actions/checkout@v4

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

      - name: Login to Container Registry
        uses: docker/login-action@v3
        with:
          registry: ${{ env.REGISTRY }}
          username: ${{ github.actor }}
          password: ${{ secrets.GITHUB_TOKEN }}

      - name: Extract metadata
        id: meta
        uses: docker/metadata-action@v5
        with:
          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
          tags: |
            type=ref,event=branch
            type=sha,prefix=
            type=semver,pattern={{version}}

      - name: Build and push
        uses: docker/build-push-action@v5
        with:
          context: .
          push: ${{ github.event_name != 'pull_request' }}
          tags: ${{ steps.meta.outputs.tags }}
          labels: ${{ steps.meta.outputs.labels }}
          cache-from: type=gha
          cache-to: type=gha,mode=max

# .github/workflows/ci-cd.yml
name: CI/CD Pipeline

on:
  push:
    branches: [main]

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Build test image
        run: docker build --target test -t myapp:test .

      - name: Run tests
        run: docker run --rm myapp:test npm test

      - name: Run linting
        run: docker run --rm myapp:test npm run lint

  build-and-push:
    needs: test
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_TOKEN }}

      - name: Build and push
        uses: docker/build-push-action@v5
        with:
          push: true
          tags: |
            username/myapp:latest
            username/myapp:${{ github.sha }}

  deploy:
    needs: build-and-push
    runs-on: ubuntu-latest
    steps:
      - name: Deploy to server
        uses: appleboy/ssh-action@v1
        with:
          host: ${{ secrets.SERVER_HOST }}
          username: ${{ secrets.SERVER_USER }}
          key: ${{ secrets.SSH_PRIVATE_KEY }}
          script: |
            docker pull username/myapp:latest
            docker compose -f docker-compose.prod.yml up -d

# Multi-stage Dockerfile with test stage
FROM node:20-alpine AS deps
WORKDIR /app
COPY package*.json ./
RUN npm ci

FROM deps AS test
COPY . .
RUN npm run lint
RUN npm test

FROM deps AS builder
COPY . .
RUN npm run build

FROM node:20-alpine AS production
WORKDIR /app
COPY --from=builder /app/dist ./dist
COPY --from=deps /app/node_modules ./node_modules
CMD ["node", "dist/server.js"]

# Enable caching with GitHub Actions cache
- name: Build and push
  uses: docker/build-push-action@v5
  with:
    context: .
    push: true
    tags: myapp:latest
    cache-from: type=gha
    cache-to: type=gha,mode=max

# Or use registry-based caching
    cache-from: type=registry,ref=myapp:cache
    cache-to: type=registry,ref=myapp:cache,mode=max