queue.js

/*
 * JavaScript tracker for Snowplow: queue.js
 * 
 * Significant portions copyright 2010 Anthon Pang. Remainder copyright 
 * 2012-2014 Snowplow Analytics Ltd. All rights reserved. 
 * 
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions are 
 * met: 
 *
 * * Redistributions of source code must retain the above copyright 
 *   notice, this list of conditions and the following disclaimer. 
 *
 * * Redistributions in binary form must reproduce the above copyright 
 *   notice, this list of conditions and the following disclaimer in the 
 *   documentation and/or other materials provided with the distribution. 
 *
 * * Neither the name of Anthon Pang nor Snowplow Analytics Ltd nor the
 *   names of their contributors may be used to endorse or promote products
 *   derived from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

;(function() {

	var
		lodash = require('./lib/lodash'),
		object = typeof exports !== 'undefined' ? exports : this; // For eventual node.js environment support

	/************************************************************
	 * Proxy object
	 * - this allows the caller to continue push()'ing to _snaq
	 *   after the Tracker has been initialized and loaded
	 ************************************************************/

	object.AsyncQueueProxy = function(asyncTracker, asyncQueue) {

		/*
		 * apply wrapper
		 *
		 * @param array parameterArray An array comprising either:
		 *      [ 'methodName', optional_parameters ]
		 * or:
		 *      [ functionObject, optional_parameters ]
		 */
		function applyAsyncFunction() {
			var i, f, parameterArray;

			for (i = 0; i < arguments.length; i += 1) {
				parameterArray = arguments[i];
				f = parameterArray.shift();

				if (lodash.isString(f)) {
					asyncTracker[f].apply(asyncTracker, parameterArray);
				} else {
					f.apply(asyncTracker, parameterArray);
				}
			}
		}

		// We need to manually apply any events collected before this initialization
		for (var i = 0; i < asyncQueue.length; i++) {
			applyAsyncFunction(asyncQueue[i]);
		}

		return {
			push: applyAsyncFunction
		};
	}

}());