Node.js Web Workers

usage_main.js

// The main node process
// Will output to shell:
// {
//  "test": "test"
// }
// "bam"

var worker = require('./webworker'),
  sys = require('sys');

var testWorker = new worker.Worker(__dirname + '/usage_worker.js');

testWorker.addListener('message', function(data) {
  sys.puts(sys.inspect(data));
});
testWorker.addListener('error', function(data) {
  sys.puts(sys.inspect(data));
});

setTimeout(function() {
  testWorker.postMessage("bam");
}, 2000);

usage_worker.js

// The worker node process
var worker = require('./webworker');

var emitter = worker.workerOpenStdio();

emitter.addListener('message', function(data) {
  worker.postMessage(data);
});

worker.postMessage({test: "test"});

webworker.js

// A Web Worker implementation for Node.js
var events = require('events');

var Worker = exports.Worker = function(filepath) {
  process.mixin(this, events.EventEmitter.prototype);
  arguments = Array.prototype.slice.call(arguments);

  try {
    this._child = process.createChildProcess('node', arguments);
  } catch (e) {
    this.emit('error', 'webworker.Worker: Failed to create child process. ' + e.toString(), filepath, null);
    return;
  }

  var self = this;
  this._child.addListener('output', function(data) {
    if (null === data)
      self.emit.call(self, 'exit');
    try {
      data = JSON.parse(data);
      self.emit.call(self, 'message', data);
    } catch (e) {
      self.emit.call(self, 'error', 'webworker.onmessage: Failed due to invalid response. ' + e.toString(), filepath, null);
    }
  });

  this._child.addListener('error', function(data) {
    if ('string' === typeof data) {
      self.emit.call(self, 'error', data, filepath, null);
    } else
      self.emit.call(self, 'error', 'webworker.onerror: Failed due to invaild response. ', filepath, null);
  });
};

Worker.prototype = {
  postMessage: function(data) {
    try {
      data = JSON.stringify(data);
      this._child.write(data);
    } catch (e) {
      this.emit('error', 'webworker.postMessage: Failed due to invalid data. ' + e.toString(), __filename, null);
    }
  },
  terminate: function() {
    this._child.kill();
  }
};

exports.postMessage = function(data) {
  try {
    data = JSON.stringify(data);
    process.stdio.write(data);
  } catch (e) {
    process.stdio.writeError('webworker.postMessage: Failed due to invalid data. ' + e.toString());
  }
};

exports.workerOpenStdio = function() {
  process.stdio.open();

  var emitter = new events.EventEmitter();

  process.stdio.addListener('data', function(data) {
    try {
      data = JSON.parse(data);
      emitter.emit('message', data);
    } catch (e) {
      emitter.emit('error', 'webworker.workerOpenStdio: Failed to parse incoming message.' + e.toString());
    }
  });

  return emitter;
};