clicks/transforms/storage.js

Browser click streams

/*
 * Copyright (c) 2012 VMware, Inc. All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

define(function (require) {
	"use strict";

	var types, undef;

	types = {
		localStorage: 'local',
		sessionStorage: 'session'
	};

	/**
	 * Attempts to detect which type of storage this object represents:
	 * 'session' or 'local'.
	 *
	 * @param storage the storage object
	 * @returns the type of storage, or undefined when unknown.
	 */
	function storageTransform(storage) {
		var type;

		try {
			for (type in types) {
				if (type in window && window[type] === storage) {
					return types[type];
				}
			}
		}
		catch (e) {
			// IE8 can throw, ignore
		}

		return undef;
	}

	return storageTransform;

});