Real-world Project — Fullstack App

fullstack-app/
├── docker-compose.yml
├── Dockerfile
├── server.js
├── package.json
└── init.sql

CREATE TABLE IF NOT EXISTS users (
  id SERIAL PRIMARY KEY,
  name VARCHAR(100) NOT NULL,
  email VARCHAR(100) UNIQUE NOT NULL
);
INSERT INTO users (name, email) VALUES
  ('Alice', 'alice@example.com'), ('Bob', 'bob@example.com');

const express = require('express');
const { Pool } = require('pg');
const app = express();
const pool = new Pool({
  host: process.env.DB_HOST || 'db',
  user: 'postgres', password: process.env.DB_PASSWORD,
  database: 'fullstack',
});
app.get('/', async (req, res) => {
  const { rows } = await pool.query('SELECT * FROM users');
  res.json({ message: 'Hello from Docker!', users: rows });
});
app.listen(3000, () => console.log('Running on 3000 🐳'));

{ "name": "fullstack-app", "scripts": { "start": "node server.js" },
  "dependencies": { "express": "^4.21.0", "pg": "^8.13.0" } }

FROM node:20-alpine
WORKDIR /app
COPY package.json package-lock.json* ./
RUN npm install --production
COPY . .
EXPOSE 3000
CMD ["node", "server.js"]

services:
  app:
    build: .
    ports: ["3000:3000"]
    environment: { DB_HOST: db, DB_PASSWORD: secret123 }
    depends_on: [db]
  db:
    image: postgres:16-alpine
    volumes:
      - pg-data:/var/lib/postgresql/data
      - ./init.sql:/docker-entrypoint-initdb.d/init.sql
    environment: { POSTGRES_PASSWORD: secret123, POSTGRES_DB: fullstack }
volumes: { pg-data: }

docker compose up -d
curl http://localhost:3000
# {"message":"Hello from Docker!","users":[{"id":1,"name":"Alice"},{"id":2,"name":"Bob"}]}

docker exec -it app sh     # Vào container
docker logs -f app         # Logs realtime
docker system prune -a     # Dọn sạch
docker compose down        # Dừng toàn bộ