Docker in Production Environment

# Development Dockerfile
FROM node:18

WORKDIR /app

COPY package*.json ./
RUN npm install

COPY . .

EXPOSE 3000

CMD ["npm", "run", "dev"]

# Development docker-compose.yml
services:
  app:
    build: .
    ports:
      - "3000:3000"
    volumes:
      - .:/app
      - /app/node_modules
    environment:
      - NODE_ENV=development
      - DEBUG=app:*
    command: npm run dev
  
  db:
    image: postgres:latest
    environment:
      POSTGRES_USER: devuser
      POSTGRES_PASSWORD: devpassword
      POSTGRES_DB: devdb
    ports:
      - "5432:5432"
    volumes:
      - pgdata:/var/lib/postgresql/data

volumes:
  pgdata:

# Production Dockerfile
FROM node:18-alpine AS builder

WORKDIR /app

# Copy package files and install dependencies
COPY package*.json ./
RUN npm ci

# Copy source code and build application
COPY . .
RUN npm run build

# Production image
FROM node:18-alpine

# Create non-root user
RUN addgroup -g 1001 appuser && \
    adduser -u 1001 -G appuser -s /bin/sh -D appuser

# Set working directory and ownership
WORKDIR /app
RUN chown -R appuser:appuser /app

# Copy from builder stage
COPY --from=builder --chown=appuser:appuser /app/package*.json ./
COPY --from=builder --chown=appuser:appuser /app/node_modules ./node_modules
COPY --from=builder --chown=appuser:appuser /app/dist ./dist

# Switch to non-root user
USER appuser

# Set environment variables
ENV NODE_ENV=production

# Expose application port
EXPOSE 3000

# Healthcheck
HEALTHCHECK --interval=30s --timeout=5s --start-period=5s --retries=3 \
  CMD wget --no-verbose --tries=1 --spider http://localhost:3000/health || exit 1

# Run the application
CMD ["node", "dist/server.js"]

# Production docker-compose.yml
services:
  app:
    image: ${REGISTRY_URL}/myapp:${VERSION}-${BUILD_NUMBER}
    deploy:
      resources:
        limits:
          cpus: '0.5'
          memory: 512M
        reservations:
          cpus: '0.25'
          memory: 256M
      restart_policy:
        condition: on-failure
        max_attempts: 3
    ports:
      - "3000:3000"
    environment:
      - NODE_ENV=production
      - DATABASE_URL=${DB_URL}
    secrets:
      - app_secret
    depends_on:
      db:
        condition: service_healthy
    healthcheck:
      test: ["CMD", "wget", "--no-verbose", "--tries=1", "--spider", "http://localhost:3000/health"]
      interval: 30s
      timeout: 5s
      retries: 3
      start_period: 5s
  
  db:
    image: postgres:14-alpine
    deploy:
      resources:
        limits:
          cpus: '1.0'
          memory: 1G
    environment:
      POSTGRES_USER: ${DB_USER}
      POSTGRES_PASSWORD_FILE: /run/secrets/db_password
      POSTGRES_DB: ${DB_NAME}
    volumes:
      - pgdata:/var/lib/postgresql/data
    secrets:
      - db_password
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U ${DB_USER}"]
      interval: 10s
      timeout: 5s
      retries: 5
      start_period: 10s

volumes:
  pgdata:
    driver: local
    driver_opts:
      type: 'none'
      o: 'bind'
      device: '/mnt/data/postgres'

secrets:
  app_secret:
    file: ./secrets/app_secret.txt
  db_password:
    file: ./secrets/db_password.txt