tcp-proxy.js

tcp-proxy.js

a simple tcp proxy

Usage

$ npm i tcp-proxy.js --save

create proxy

const TCPProxy = require('tcp-proxy.js');
const proxy = new TCPProxy({ port: 9229 });
proxy.createProxy({
  forwardPort: 9999,
  forwardHost: 'localhost',
});

end proxy

proxy.end();

interceptor

proxy.createProxy({
  forwardPort: 9999,
  interceptor: {
    client(chunk) {
      // request => proxy server => interceptor.client => forward server
      const data = chunk.toString();
      const newData = data.replace('GET / ', 'GET /tom ');
      return Buffer.from(newData);
    },
    server(chunk) {
      // forward server => interceptor.server => proxy server => response
      const data = chunk.toString();
      const newData = data.replace('hello tom', 'bello tom');
      return Buffer.from(newData);
    },
  },
});

async interceptor

proxy.createProxy({
  forwardPort: 9999,
  interceptor: {
    client(chunk) {
      // request => proxy server => interceptor.client => forward server
      const data = chunk.toString();
      return new Promise(resolve => {
        setTimeout(() => {
          const newData = data.replace('GET / ', 'GET /tom ');
          resolve(Buffer.from(newData));
        }, 200);
      });
    },
  },
});