node.js debug server proxy with automatic launching of a target file named "main.js" as a child.

nodeJsServerProxy.js

var require;
var net = require("net");
var sys = require("sys");
var fs = require("fs");
var child_process = require("child_process");


var encoding = "binary";
var remote;
var main;

var comLogFd = fs.openSync('/home/mashare/Dropbox/mashare/server/control/comLogFd', 'w');
console.log('comLogFd' + comLogFd);
fs.writeSync(comLogFd, 'Debug Proxy Log:');
 
var server = net.createServer(function (proxyStream) {
  proxyStream.setEncoding(encoding);
  proxyStream.setNoDelay();
  proxyStream.addListener('connect', function () {
    console.log('proxy connect request');
    console.log('1. main = ' + String(main));
    var mainReady = false;
    if (main) {
      console.log('killing previous main');
      main.removeAllListeners('exit');
      main.kill();
    }
    if (remote) {
      console.log('ending remote connection');
      remote.removeAllListeners('end');
      remote.end();
    }
    main = child_process.spawn('node', ['--debug', 'main.js']);
    console.log('2. main = ' + String(main));
    main.stdout.setEncoding('utf8');
    main.stderr.setEncoding('utf8');
    
    main.stderr.on('data', function (data) {
      console.log('main: stderr: ' + data);
    });
    main.on('exit', function (code) {
      console.log('main exited with code ' + code);
    });

    main.stdout.on('data', function (data) {
      console.log('main: ' + data);
      if (! mainReady && data.slice(0, 5) === 'ready') {
        mainReady = true;
        console.log('connecting to localhost:5858');
        remote = net.createConnection(5858, "localhost");
        remote.setEncoding(encoding);
        remote.setTimeout(0);
    
        remote.addListener("connect", function () {
          console.log('remote connect');
        });
    
        remote.addListener("data", function (data) {
          console.log('rem->prxy: ' + String(data).slice(0, 120));
          fs.writeSync(comLogFd, '\nrem->prxy:\n');
          fs.writeSync(comLogFd, data);
          if (String(data).length > 120) {
            console.log('    ...' + String(data).slice(-Math.min(80, String(data).length - 120)));
          }
          proxyStream.write(data, encoding);
//          proxyStream.write(data);
        });
    
        remote.addListener("end", function () {
          console.log('remote end event');
          proxyStream.end();
          remote.end();
        });
      }
    });
    console.log('finished proxy connect');
  });
  proxyStream.addListener('data', function (data) {
    console.log('prxy->rem:' + String(data).slice(0, 120));
    fs.writeSync(comLogFd, '\nprxy->rem:\n');
    fs.writeSync(comLogFd, data);
    remote.write(data, encoding);
  });
  proxyStream.addListener('drain', function () {
    console.log('proxy write drained');
  });
  proxyStream.addListener('end', function () {
    console.log('proxy end event');
    main.kill();
    proxyStream.end();
    if (remote) {
      remote.end();
    }
  });
});
server.listen(7000);