Docker untuk Developer: Panduan Praktis

# docker-compose.yml
# Aplikasi Web + Database + Redis
version: "3.8"

services:
  # === Aplikasi Web (Node.js) ===
  web:
    build:
      context: .
      dockerfile: Dockerfile
    container_name: web-app
    ports:
      - "3000:3000"
    environment:
      - NODE_ENV=production
      - DATABASE_URL=postgresql://user:password@db:5432/myapp
      - REDIS_URL=redis://cache:6379
    volumes:
      - ./uploads:/app/uploads
    depends_on:
      db:
        condition: service_healthy
      cache:
        condition: service_started
    networks:
      - app-network
    restart: unless-stopped

  # === Database PostgreSQL ===
  db:
    image: postgres:16-alpine
    container_name: postgres-db
    environment:
      POSTGRES_USER: user
      POSTGRES_PASSWORD: password
      POSTGRES_DB: myapp
    volumes:
      - postgres-data:/var/lib/postgresql/data
      - ./init.sql:/docker-entrypoint-initdb.d/init.sql
    ports:
      - "5432:5432"
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U user -d myapp"]
      interval: 10s
      timeout: 5s
      retries: 5
    networks:
      - app-network
    restart: unless-stopped

  # === Redis Cache ===
  cache:
    image: redis:7-alpine
    container_name: redis-cache
    command: redis-server --maxmemory 256mb --maxmemory-policy allkeys-lru
    volumes:
      - redis-data:/data
    networks:
      - app-network
    restart: unless-stopped

  # === Nginx Reverse Proxy ===
  nginx:
    image: nginx:alpine
    container_name: nginx-proxy
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - ./nginx.conf:/etc/nginx/nginx.conf:ro
      - ./ssl:/etc/nginx/ssl:ro
    depends_on:
      - web
    networks:
      - app-network
    restart: unless-stopped

volumes:
  postgres-data:
  redis-data:

networks:
  app-network:
    driver: bridge

# Jalankan semua layanan (foreground)
docker compose up

# Jalankan di background (detached)
docker compose up -d

# Build ulang image sebelum start
docker compose up --build

# Hentikan semua layanan
docker compose down

# Hentikan dan hapus volumes (HATI-HATI: data hilang!)
docker compose down -v

# Lihat status layanan
docker compose ps

# Lihat log layanan tertentu
docker compose logs web
docker compose logs -f db   # -f = follow (live)

# Jalankan perintah di dalam container
docker compose exec web npm run migrate
docker compose exec db psql -U user -d myapp

# Scale layanan tertentu
docker compose up -d --scale web=3

# Restart satu layanan
docker compose restart web