queen/lib/server/worker.js

A platform for running scripts on many browsers

var	generateId = require('node-uuid').v4,
	its = require('its'),
	utils = require('./utils.js');
	
var create = module.exports = function(id, provider, emitter, onSendToSocket){
	var worker = new Worker(id, provider, emitter, onSendToSocket);

	return worker.api;
};

var Worker = function(id, provider, emitter, onSendToSocket){
	its.object(emitter, 'An emitter is required');
	its.object(provider, 'A provider is required');
	its.defined(id, 'An id is required');
	its.func(onSendToSocket, 'A send to socket callback is required');

	var self = this;

	this.id = id;
	this.provider = provider;
	this.emitter = emitter;
	this.sendToSocket = onSendToSocket;
	this.kill = utils.once(this.kill.bind(this));

	emitter.on('dead', function(){
		self.kill = utils.noop;
		self.emitter.removeAllListeners();
	});

	Object.defineProperty(this, 'api', { 
		value: Object.freeze(getApi.call(this)),
		enumerable: true 
	});
};

var getApi = function(){
	var self = this,
		api = this.sendToSocket.bind(this);

	api.on = this.emitter.on.bind(this.emitter);
	api.removeListener = this.emitter.removeListener.bind(this.emitter);
	api.kill = this.kill;
	api.id = this.id;

	Object.defineProperty(api, 'provider', {
		get: function(){ return self.provider; },
		enumerable: true
	});

	return api;
};

Worker.prototype.kill = function(reason){
	this.emitter.emit('dead', reason);
	this.emitter.removeAllListeners();
};