npm install http-proxy --save

const http = require('http');
const httpProxy = require('http-proxy');
//创建一个代理服务
const proxy = httpProxy.createProxyServer();
//创建http服务器并监听8888端口
let server = http.createServer(function (req, res) {
  //将用户的请求转发到本地9999端口上
  proxy.web(req, res, {
    target: 'http://localhost:9999'
  });
  //监听代理服务错误
  proxy.on('error', function (err) {
    console.log(err);
  });
});
server.listen(8888, '0.0.0.0');

const http = require('http');
http.createServer(function (req, res) {
  res.end('port : 9999');
}).listen(9999, '0.0.0.0');

const http = require('http');
const httpProxy = require('http-proxy');
//创建一个代理服务
const proxy = httpProxy.createProxyServer();
//虚拟主机
const hosts = {
  'www.a.me': 'http://localhost:8888',
  'www.b.me': 'http://localhost:9999',
};
//创建http服务器并监听80端口
let server = http.createServer(function (req, res) {
  //获取主机名
  let host = req.headers['host'];
  host = host.split(':')[0];
  //根据主机名，找到要代理的服务
  let target = hosts[host];
  if (target) {
    proxy.web(req, res, {
      target: target
    });
    proxy.on('error', function (err) {
      console.log(err);
    });
  } else {
    res.end('end');
  }
});
server.listen(80, '0.0.0.0');

const http = require('http');
http.createServer(function (req, res) {
  res.end('port : 8888');
}).listen(8888, '0.0.0.0');

const http = require('http');
http.createServer(function (req, res) {
  res.end('port : 9999');
}).listen(9999, '0.0.0.0');