如何在服务器和客户端之间传输流数据？

在服务器端，可以使用Node.js来建立Websocket连接，客户端使用JavaScript来连接Websocket。下面是具体实现步骤：

1. 安装node.js和websocket库

npm install websocket

2. 在服务器端建立WebSocket连接，并处理数据传输

const WebSocketServer = require('websocket').server;
const http = require('http');

const httpServer = http.createServer((req, res) => {});
httpServer.listen(8080, () => {
  console.log('Server is listening on port 8080');
});

const webSocketServer = new WebSocketServer({
  httpServer
});

webSocketServer.on('request', request => {
  const connection = request.accept(null, request.origin);

  console.log('Client connected');
  
  connection.on('message', message => {
    console.log(`Received message: ${message.utf8Data}`);
    connection.sendUTF('Message received.');
  });

  connection.on('close', (reasonCode, description) => {
    console.log('Client disconnected');
  });
});

3. 在客户端连接WebSocket，发送和接收数据

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

socket.addEventListener('open', event => {
  console.log('Connection opened');
  socket.send('Hello WebSocket!');
});

socket.addEventListener('message', event => {
  console.log(`Received message: ${event.data}`);
});

socket.addEventListener('close', event => {
  console.log('Connection closed');
});

这样，就可以在服务器和客户端之间实现流式数据传输了。例如，可以将音频、视频和其他实时数据传输到Web应用程序。