workers-manager

Web worker manager ( Can be used both as Node module and in browsers ).

( If you are reading this page on npmjs.org, I recommend you read it on Github workers-manager, because on Github it is more readable.)

Browser support

Chrome, Safari, Firefox, Opera, IE10+

Installation

    npm install workers-manager

Usage

You can use it both in Node environment and in browsers.

• Use it as a Node module.

 
    var WorkersManager = require('workers-manager');
 
    /**
    * Imagine you have a Class called Company.
    */
    var Company = function () {
        this._init();
    };
    Company.prototype = {
        constructor: Company,
 
        /**
        * Assume we have an array [[0], [1,1], [1,2,3]]
        * and assume sum.js will add the numbers in each element of this array,
        * and return [0, 2, 6];
        * 
        * Note that navigator.hardwareConcurrency is not support by all browsers.
        */
        _init: function () {
            this._workerMgr = new WorkersManager();             // Initialize WorkersManager.
            this._workerMgr.setPath('test/workers/sum.js')      // Set file path.
                           .setNumOfWorkers(navigator.hardwareConcurrency || 2)     // Default is 1.
                           .events.bind('message', this._receivedMsg.bind(this))    // Bind events.
                                  .bind('error',   this._receivedErr.bind(this));   // Chainable.
        },
 
        getWorkerMgr: function () {
            return this._workerMgr;
        },
 
        /**
        * WorkersManager will return processed data all together.
        */
        _receivedMsg: function (workerMgr, msg) {
        },
 
        _receivedErr: function (workerMgr, msgErr) {
        }
    };
 
    var company = new Company(),
        mgr     = company.getWorkerMgr(),
        /**
        * Fake data
        */
        data    = [[1,2], [1,1,1], [0], [4], [1,1,1,1,1], [2,2], [-1,1], [0], [12]];  // data.length === 9
 
    mgr.setData(data)           // Set an array of data that you want workers to process.
       .startWork();            // Tell workers to work.
 
    /**
    * `message` event listener `_receivedMsg` will get noticed once all workers finished
    * that work.
    */
    _receivedMsg: function (workerMgr, msg) {
        msg.length      // 9
        msg             // [3,3,0,4,5,4,0,0,12]
    }
 

• Use it directly in a browser. You can put workersManager.js in your project and include it by html script tag. ( This module depends on events.js, you need to bring events.js along with it.)

 
    /**
    * Before you use it in browsers, you probably will want to replace 'nameSpace' with a real 
    * namespace, and remove the use of `webworker-threads` since browsers support `Worker` natively.
    * Simply update `workersManager.js`.
    */
 

• Public interface in this module. ( The code of workersManager.js is clean and well organized, I recommend you read it directly.)

 
    constructor: WorkersManager
 
 
    /**
     * Destroy the instance, it will `terminate` all workers.
     * @return <em>undefined</em>
     */
    destroy: function ()
 
 
    /**
    * @param path {String} -  Only accept .js file.
    * @returns {WorkersManager} A pointer to this instance, allowing call chaining.
    */
    setPath: function (path)
 
 
    hasErr: function ()
 
 
    /**
    * It will throw error if passing in an empty array.
    * 
    * @param data {Array} 
    * @returns {WorkersManager} A pointer to this instance, allowing call chaining.
    */
    setData: function (data)
 
 
    /**
    * Default number of workers is 1.
    * 
    * @param num {Positive Integer}
    * @returns {WorkersManager} A pointer to this instance, allowing call chaining.
    */
    setNumOfWorkers: function (num)
 
 
    /**
    * If file path or `data` is not set, calling this method will throw error.
    * 
    * You also don't need to worry about the case that the length of `data` is 
    * smaller than the number of web workers. It will handle it well.
    * 
    * @returns {WorkersManager} A pointer to this instance, allowing call chaining.
    */
    startWork: function ()

Tests

    npm test