安装 Express 和 http-proxy

npm install --save express http-proxy

反向代理代码

proxy.js

var express = require(‘express‘);
var app = express();
var httpProxy = require(‘http-proxy‘);
var apiProxy = httpProxy.createProxyServer();
var serverOne = ‘http://localhost:3001‘,
    ServerTwo = ‘http://localhost:3002‘;

// 访问 http://localhost:3000/server1 时，代理 http://localhost:3001/server1
app.all("/server1", function(req, res) {
    apiProxy.web(req, res, {
        target: serverOne
    });
});

// 访问 http://localhost:3000/server2 时，代理 http://localhost:3002/server2
app.all("/server2", function(req, res) {
    apiProxy.web(req, res, {
        target: ServerTwo
    });
});

// 访问 http://localhost:3000/xxx 时，代理 http://localhost:3001/xxx
app.all("/*", function(req, res) {
    apiProxy.web(req, res, {
        target: serverOne
    });
});

app.listen(3000);

服务代码

server.js

const express = require(‘express‘);
const server = express();
const server2 = express();
server.get(‘/*‘, function(req, res) {
    res.send(`Hello world From Server 1 <br> req.path : ${req.path}`);
});
server2.get(‘/*‘, function(req, res) {
    res.send(`Hello world From Server 2 <br> req.path : ${req.path}`);
});

// serverOne
server.listen(3001);
// ServerTwo
server2.listen(3002);

测试

1. 分别启动 server.js 和 proxy.js：node proxy，node server
2. 浏览器访问http://localhost:3000/server1等地址进行测试

参考

Reverse proxy using ExpressJS – Codeforgeek