nodejs 简单的模拟代理服务器

• https://nodejs.org/api/net.html#net_net_createconnection

代理前：client -> server

代理后：client -> proxy -> server

game-client.js:

const net = require("net");

const serverAddress = {
  host: "127.0.0.1",
  port: 5000,
};
const proxyAddress = {
  host: "127.0.0.1",
  port: 3000,
};

let a = 0;

// 这里要处理的就是，如何把client请求地址，指向我编写的代理服务器
const client = net.createConnection(proxyAddress, () => {
  console.log("client start port is: " + client.address().port);

  setInterval(() => {
    console.log(`--> ${a}`);
    client.write(a.toString());
    a++;
  }, 1000);
});

client.on("data", (data) => {
  console.log("<-- " + data.toString());
});

client.on("end", () => {
  console.log("与服务器断开连接");
});
client.on("error", () => {
  console.log(`Error`);
});
client.on("timeout", () => {
  console.log(`Timeout`);
});
client.on("close", () => {
  console.log(`Close`);
});

game-server.js:

const net = require("net");

const server = net.createServer((c) => {
  server.getConnections((e, count) => console.log("Count: " + count));

  c.on("data", (data) => {
    c.write(data.toString());
    // c.end(); // 主动断开与客户端的连接
  });
  c.on("end", () => {
    console.log(`客户端End`);
  });
  c.on("error", () => {
    console.log(`客户端Error`);
    c.destroy();
  });
  c.on("timeout", () => {
    console.log(`客户端Timeout`);
  });
  c.on("close", () => {
    console.log(`客户端Close`);
    c.destroy();
  });
});

server.listen(5000, () => {
  console.log("server start port is: " + server.address().port);
});

game-proxy-server.js

const net = require("net");

const serverAddress = {
  host: "127.0.0.1",
  port: 5000,
};
let _clientSocket = null;

// 创建一个客户端与game server联系
const client = net.createConnection(serverAddress);

// 将服务器返回的数据，返给client
client.on("data", (data) => {
  console.log("proxy send client " + data);
  if (_clientSocket) _clientSocket.write(data);
});

// 创建代理服务器与game client联系
const server = net.createServer((clientSocket) => {
  _clientSocket = clientSocket;

  // 接受client的消息，转发给服务器
  clientSocket.on("data", (data) => {
    // 发给服务器
    console.log("proxy send server " + data);
    client.write(data);
  });

  clientSocket.on("end", () => {
    console.log(`game client End`);
  });
  clientSocket.on("error", () => {
    clientSocket.destroy();
  });
  clientSocket.on("timeout", () => {
    console.log(`game client Timeout`);
  });
  clientSocket.on("close", () => {
    clientSocket.destroy();
  });
});

server.listen(3000, () => {
  console.log("proxy server start port is: " + server.address().port);
});

client print:

client start port is:  6259
--> 0
<-- 0
--> 1
<-- 1
--> 2

prixy print:

proxy server start port is: 3000
proxy send server0
proxy send client0
proxy send server1
proxy send client1