使用Node.js构建可靠的后端应用程序

const http = require('http');

const server = http.createServer((req, res) => {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Hello, World!');
});

server.listen(3000, 'localhost', () => {
  console.log('Server is running at http://localhost:3000');
});

如何使用Node.js创建简单的HTTP服务器

const http = require('http');

const server = http.createServer((req, res) => {
  console.log('Received request for ' + req.url);
  
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.write('Hello, World!');
  res.end();
});

server.listen(3000, () => {
  console.log('Server is running on port 3000');
});

使用Node.js和Express.js创建 RESTful API

const express = require('express');
const bodyParser = require('body-parser');

const app = express();
app.use(bodyParser.json());

app.get('/api/users', (req, res) => {
  // 从数据库获取所有用户
  const users = [
    { id: 1, name: 'John Doe' },
    { id: 2, name: 'Jane Smith' },
    { id: 3, name: 'Bob Johnson' }
  ];

  res.json(users);
});

app.post('/api/users', (req, res) => {
  // 创建新用户
  const newUser = req.body;

  res.status(201).json(newUser);
});

app.listen(3000, () => {
  console.log('Server is running on port 3000');
});

如何使用Node.js处理文件上传

const fs = require('fs');
const http = require('http');

const server = http.createServer((req, res) => {
  if (req.method === 'POST') {
    const fileStream = fs.createWriteStream('uploaded_file.txt');
    req.pipe(fileStream);

    req.on('end', () => {
      res.writeHead(200, {'Content-Type': 'text/plain'});
      res.end('File uploaded successfully!');
    });
  }
});

server.listen(3000, () => {
  console.log('Server is running on port 3000');
});

使用Node.js和WebSocket创建实时聊天应用

const http = require('http');
const WebSocket = require('ws');

const server = http.createServer();
const wss = new WebSocket.Server({ server });

wss.on('connection', (ws) => {
  ws.on('message', (message) => {
    // 处理收到的消息

    wss.clients.forEach((client) => {
      if (client !== ws && client.readyState === WebSocket.OPEN) {
        // 发送消息给其他客户端
        client.send(message);
      }
    });
  });

  ws.on('close', () => {
    // 处理客户端断开连接
  });
});

server.listen(3000, () => {
  console.log('WebSocket server is running on port 3000');
});