node.js WebSocket

Node.js原生API没有提供对WebSocket的支持，需要安装第三方包才能使用WebSocket功能。可以使用ws模块来实现WebSocket功能。以下是一个简单的例子，演示如何创建WebSocket服务器和客户端：

1.创建WebSocket服务器：

const WebSocket = require('ws');
const server = new WebSocket.Server({ port: 8080 });

server.on('connection', function connection(ws) {
  console.log('client connected');  ws.send('Welcome to WebSocket server!');

  ws.on('message', function incoming(message) {
    console.log('received: %s', message);
    ws.send('You said: ' + message);
  });

  ws.on('close', function close() {
    console.log('client disconnected');
  });
});

2.创建WebSocket客户端：

const WebSocket = require('ws');
const ws = new WebSocket('ws://localhost:8080');

ws.on('open', function open() {
  console.log('connected');
  ws.send('Hello, WebSocket server!');
});

ws.on('message', function incoming(data) {
  console.log('received: %s', data);
});

ws.on('close', function close() {
  console.log('disconnected');
});