/*
* ----------------------------- JSTORAGE -------------------------------------
* Simple local storage wrapper to save data on the browser side, supporting
* all major browsers - IE6+, Firefox2+, Safari4+, Chrome4+ and Opera 10.5+
*
* Copyright (c) 2010 - 2012 Andris Reinman, andris.reinman@gmail.com
* Project homepage: www.jstorage.info
*
* Licensed under MIT-style license:
*
* 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 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.
*/
(function(){
var
/* jStorage version */
JSTORAGE_VERSION = "0.3.0",
/* detect a dollar object or create one if not found */
$ = window.jQuery || window.$ || (window.$ = {}),
/* check for a JSON handling support */
JSON = {
parse:
window.JSON && (window.JSON.parse || window.JSON.decode) ||
String.prototype.evalJSON && function(str){return String(str).evalJSON();} ||
$.parseJSON ||
$.evalJSON,
stringify:
Object.toJSON ||
window.JSON && (window.JSON.stringify || window.JSON.encode) ||
$.toJSON
};
// Break if no JSON support was found
if(!JSON.parse || !JSON.stringify){
throw new Error("No JSON support found, include //cdnjs.cloudflare.com/ajax/libs/json2/20110223/json2.js to page");
}
var
/* This is the object, that holds the cached values */
_storage = {},
/* Actual browser storage (localStorage or globalStorage['domain']) */
_storage_service = {jStorage:"{}"},
/* DOM element for older IE versions, holds userData behavior */
_storage_elm = null,
/* How much space does the storage take */
_storage_size = 0,
/* which backend is currently used */
_backend = false,
/* onchange observers */
_observers = {},
/* timeout to wait after onchange event */
_observer_timeout = false,
/* last update time */
_observer_update = 0,
/* pubsub observers */
_pubsub_observers = {},
/* skip published items older than current timestamp */
_pubsub_last = +new Date(),
/* Next check for TTL */
_ttl_timeout,
/* crc32 table */
_crc32Table = "00000000 77073096 EE0E612C 990951BA 076DC419 706AF48F E963A535 9E6495A3 "+
"0EDB8832 79DCB8A4 E0D5E91E 97D2D988 09B64C2B 7EB17CBD E7B82D07 90BF1D91 1DB71064 "+
"6AB020F2 F3B97148 84BE41DE 1ADAD47D 6DDDE4EB F4D4B551 83D385C7 136C9856 646BA8C0 "+
"FD62F97A 8A65C9EC 14015C4F 63066CD9 FA0F3D63 8D080DF5 3B6E20C8 4C69105E D56041E4 "+
"A2677172 3C03E4D1 4B04D447 D20D85FD A50AB56B 35B5A8FA 42B2986C DBBBC9D6 ACBCF940 "+
"32D86CE3 45DF5C75 DCD60DCF ABD13D59 26D930AC 51DE003A C8D75180 BFD06116 21B4F4B5 "+
"56B3C423 CFBA9599 B8BDA50F 2802B89E 5F058808 C60CD9B2 B10BE924 2F6F7C87 58684C11 "+
"C1611DAB B6662D3D 76DC4190 01DB7106 98D220BC EFD5102A 71B18589 06B6B51F 9FBFE4A5 "+
"E8B8D433 7807C9A2 0F00F934 9609A88E E10E9818 7F6A0DBB 086D3D2D 91646C97 E6635C01 "+
"6B6B51F4 1C6C6162 856530D8 F262004E 6C0695ED 1B01A57B 8208F4C1 F50FC457 65B0D9C6 "+
"12B7E950 8BBEB8EA FCB9887C 62DD1DDF 15DA2D49 8CD37CF3 FBD44C65 4DB26158 3AB551CE "+
"A3BC0074 D4BB30E2 4ADFA541 3DD895D7 A4D1C46D D3D6F4FB 4369E96A 346ED9FC AD678846 "+
"DA60B8D0 44042D73 33031DE5 AA0A4C5F DD0D7CC9 5005713C 270241AA BE0B1010 C90C2086 "+
"5768B525 206F85B3 B966D409 CE61E49F 5EDEF90E 29D9C998 B0D09822 C7D7A8B4 59B33D17 "+
"2EB40D81 B7BD5C3B C0BA6CAD EDB88320 9ABFB3B6 03B6E20C 74B1D29A EAD54739 9DD277AF "+
"04DB2615 73DC1683 E3630B12 94643B84 0D6D6A3E 7A6A5AA8 E40ECF0B 9309FF9D 0A00AE27 "+
"7D079EB1 F00F9344 8708A3D2 1E01F268 6906C2FE F762575D 806567CB 196C3671 6E6B06E7 "+
"FED41B76 89D32BE0 10DA7A5A 67DD4ACC F9B9DF6F 8EBEEFF9 17B7BE43 60B08ED5 D6D6A3E8 "+
"A1D1937E 38D8C2C4 4FDFF252 D1BB67F1 A6BC5767 3FB506DD 48B2364B D80D2BDA AF0A1B4C "+
"36034AF6 41047A60 DF60EFC3 A867DF55 316E8EEF 4669BE79 CB61B38C BC66831A 256FD2A0 "+
"5268E236 CC0C7795 BB0B4703 220216B9 5505262F C5BA3BBE B2BD0B28 2BB45A92 5CB36A04 "+
"C2D7FFA7 B5D0CF31 2CD99E8B 5BDEAE1D 9B64C2B0 EC63F226 756AA39C 026D930A 9C0906A9 "+
"EB0E363F 72076785 05005713 95BF4A82 E2B87A14 7BB12BAE 0CB61B38 92D28E9B E5D5BE0D "+
"7CDCEFB7 0BDBDF21 86D3D2D4 F1D4E242 68DDB3F8 1FDA836E 81BE16CD F6B9265B 6FB077E1 "+
"18B74777 88085AE6 FF0F6A70 66063BCA 11010B5C 8F659EFF F862AE69 616BFFD3 166CCF45 "+
"A00AE278 D70DD2EE 4E048354 3903B3C2 A7672661 D06016F7 4969474D 3E6E77DB AED16A4A "+
"D9D65ADC 40DF0B66 37D83BF0 A9BCAE53 DEBB9EC5 47B2CF7F 30B5FFE9 BDBDF21C CABAC28A "+
"53B39330 24B4A3A6 BAD03605 CDD70693 54DE5729 23D967BF B3667A2E C4614AB8 5D681B02 "+
"2A6F2B94 B40BBE37 C30C8EA1 5A05DF1B 2D02EF8D",
/**
* XML encoding and decoding as XML nodes can't be JSON'ized
* XML nodes are encoded and decoded if the node is the value to be saved
* but not if it's as a property of another object
* Eg. -
* $.jStorage.set("key", xmlNode); // IS OK
* $.jStorage.set("key", {xml: xmlNode}); // NOT OK
*/
_XMLService = {
/**
* Validates a XML node to be XML
* based on jQuery.isXML function
*/
isXML: function(elm){
var documentElement = (elm ? elm.ownerDocument || elm : 0).documentElement;
return documentElement ? documentElement.nodeName !== "HTML" : false;
},
/**
* Encodes a XML node to string
* based on http://www.mercurytide.co.uk/news/article/issues-when-working-ajax/
*/
encode: function(xmlNode) {
if(!this.isXML(xmlNode)){
return false;
}
try{ // Mozilla, Webkit, Opera
return new XMLSerializer().serializeToString(xmlNode);
}catch(E1) {
try { // IE
return xmlNode.xml;
}catch(E2){}
}
return false;
},
/**
* Decodes a XML node from string
* loosely based on http://outwestmedia.com/jquery-plugins/xmldom/
*/
decode: function(xmlString){
var dom_parser = ("DOMParser" in window && (new DOMParser()).parseFromString) ||
(window.ActiveXObject && function(_xmlString) {
var xml_doc = new ActiveXObject('Microsoft.XMLDOM');
xml_doc.async = 'false';
xml_doc.loadXML(_xmlString);
return xml_doc;
}),
resultXML;
if(!dom_parser){
return false;
}
resultXML = dom_parser.call("DOMParser" in window && (new DOMParser()) || window, xmlString, 'text/xml');
return this.isXML(resultXML)?resultXML:false;
}
},
_localStoragePolyfillSetKey = function(){};
////////////////////////// PRIVATE METHODS ////////////////////////
/**
* Initialization function. Detects if the browser supports DOM Storage
* or userData behavior and behaves accordingly.
*/
function _init(){
/* Check if browser supports localStorage */
var localStorageReallyWorks = false;
if("localStorage" in window){
try {
window.localStorage.setItem('_tmptest', 'tmpval');
localStorageReallyWorks = true;
window.localStorage.removeItem('_tmptest');
} catch(BogusQuotaExceededErrorOnIos5) {
// Thanks be to iOS5 Private Browsing mode which throws
// QUOTA_EXCEEDED_ERRROR DOM Exception 22.
}
}
if(localStorageReallyWorks){
try {
if(window.localStorage) {
_storage_service = window.localStorage;
_backend = "localStorage";
_observer_update = _storage_service.jStorage_update;
}
} catch(E3) {/* Firefox fails when touching localStorage and cookies are disabled */}
}
/* Check if browser supports globalStorage */
else if("globalStorage" in window){
try {
if(window.globalStorage) {
_storage_service = window.globalStorage[window.location.hostname];
_backend = "globalStorage";
_observer_update = _storage_service.jStorage_update;
}
} catch(E4) {/* Firefox fails when touching localStorage and cookies are disabled */}
}
/* Check if browser supports userData behavior */
else {
_storage_elm = document.createElement('link');
if(_storage_elm.addBehavior){
/* Use a DOM element to act as userData storage */
_storage_elm.style.behavior = 'url(#default#userData)';
/* userData element needs to be inserted into the DOM! */
document.getElementsByTagName('head')[0].appendChild(_storage_elm);
try{
_storage_elm.load("jStorage");
}catch(E){
// try to reset cache
_storage_elm.setAttribute("jStorage", "{}");
_storage_elm.save("jStorage");
_storage_elm.load("jStorage");
}
var data = "{}";
try{
data = _storage_elm.getAttribute("jStorage");
}catch(E5){}
try{
_observer_update = _storage_elm.getAttribute("jStorage_update");
}catch(E6){}
_storage_service.jStorage = data;
_backend = "userDataBehavior";
}else{
_storage_elm = null;
return;
}
}
// Load data from storage
_load_storage();
// remove dead keys
_handleTTL();
// create localStorage and sessionStorage polyfills if needed
_createPolyfillStorage("local");
_createPolyfillStorage("session");
// start listening for changes
_setupObserver();
// initialize publish-subscribe service
_handlePubSub();
// handle cached navigation
if("addEventListener" in window){
window.addEventListener("pageshow", function(event){
if(event.persisted){
_storageObserver();
}
}, false);
}
}
/**
* Create a polyfill for localStorage (type="local") or sessionStorage (type="session")
*
* @param {String} type Either "local" or "session"
* @param {Boolean} forceCreate If set to true, recreate the polyfill (needed with flush)
*/
function _createPolyfillStorage(type, forceCreate){
var _skipSave = false,
_length = 0,
i,
storage,
storage_source = {};
var rand = Math.random();
if(!forceCreate && typeof window[type+"Storage"] != "undefined"){
return;
}
// Use globalStorage for localStorage if available
if(type == "local" && window.globalStorage){
localStorage = window.globalStorage[window.location.hostname];
return;
}
// only IE6/7 from this point on
if(_backend != "userDataBehavior"){
return;
}
// Remove existing storage element if available
if(forceCreate && window[type+"Storage"] && window[type+"Storage"].parentNode){
window[type+"Storage"].parentNode.removeChild(window[type+"Storage"]);
}
storage = document.createElement("button");
document.getElementsByTagName('head')[0].appendChild(storage);
if(type == "local"){
storage_source = _storage;
}else if(type == "session"){
_sessionStoragePolyfillUpdate();
}
for(i in storage_source){
if(storage_source.hasOwnProperty(i) && i != "__jstorage_meta" && i != "length" && typeof storage_source[i] != "undefined"){
if(!(i in storage)){
_length++;
}
storage[i] = storage_source[i];
}
}
// Polyfill API
/**
* Indicates how many keys are stored in the storage
*/
storage.length = _length;
/**
* Returns the key of the nth stored value
*
* @param {Number} n Index position
* @return {String} Key name of the nth stored value
*/
storage.key = function(n){
var count = 0, i;
_sessionStoragePolyfillUpdate();
for(i in storage_source){
if(storage_source.hasOwnProperty(i) && i != "__jstorage_meta" && i!="length" && typeof storage_source[i] != "undefined"){
if(count == n){
return i;
}
count++;
}
}
}
/**
* Returns the current value associated with the given key
*
* @param {String} key key name
* @return {Mixed} Stored value
*/
storage.getItem = function(key){
_sessionStoragePolyfillUpdate();
if(type == "session"){
return storage_source[key];
}
return $.jStorage.get(key);
}
/**
* Sets or updates value for a give key
*
* @param {String} key Key name to be updated
* @param {String} value String value to be stored
*/
storage.setItem = function(key, value){
if(typeof value == "undefined"){
return;
}
storage[key] = (value || "").toString();
}
/**
* Removes key from the storage
*
* @param {String} key Key name to be removed
*/
storage.removeItem = function(key){
if(type == "local"){
return $.jStorage.deleteKey(key);
}
storage[key] = undefined;
_skipSave = true;
if(key in storage){
storage.removeAttribute(key);
}
_skipSave = false;
}
/**
* Clear storage
*/
storage.clear = function(){
if(type == "session"){
window.name = "";
_createPolyfillStorage("session", true);
return;
}
$.jStorage.flush();
}
if(type == "local"){
_localStoragePolyfillSetKey = function(key, value){
if(key == "length"){
return;
}
_skipSave = true;
if(typeof value == "undefined"){
if(key in storage){
_length--;
storage.removeAttribute(key);
}
}else{
if(!(key in storage)){
_length++;
}
storage[key] = (value || "").toString();
}
storage.length = _length;
_skipSave = false;
}
}
function _sessionStoragePolyfillUpdate(){
if(type != "session"){
return;
}
try{
storage_source = JSON.parse(window.name || "{}");
}catch(E){
storage_source = {};
}
}
function _sessionStoragePolyfillSave(){
if(type != "session"){
return;
}
window.name = JSON.stringify(storage_source);
};
storage.attachEvent("onpropertychange", function(e){
if(e.propertyName == "length"){
return;
}
if(_skipSave || e.propertyName == "length"){
return;
}
if(type == "local"){
if(!(e.propertyName in storage_source) && typeof storage[e.propertyName] != "undefined"){
_length ++;
}
}else if(type == "session"){
_sessionStoragePolyfillUpdate();
if(typeof storage[e.propertyName] != "undefined" && !(e.propertyName in storage_source)){
storage_source[e.propertyName] = storage[e.propertyName];
_length++;
}else if(typeof storage[e.propertyName] == "undefined" && e.propertyName in storage_source){
delete storage_source[e.propertyName];
_length--;
}else{
storage_source[e.propertyName] = storage[e.propertyName];
}
_sessionStoragePolyfillSave();
storage.length = _length;
return;
}
$.jStorage.set(e.propertyName, storage[e.propertyName]);
storage.length = _length;
});
window[type+"Storage"] = storage;
}
/**
* Reload data from storage when needed
*/
function _reloadData(){
var data = "{}";
if(_backend == "userDataBehavior"){
_storage_elm.load("jStorage");
try{
data = _storage_elm.getAttribute("jStorage");
}catch(E5){}
try{
_observer_update = _storage_elm.getAttribute("jStorage_update");
}catch(E6){}
_storage_service.jStorage = data;
}
_load_storage();
// remove dead keys
_handleTTL();
_handlePubSub();
}
/**
* Sets up a storage change observer
*/
function _setupObserver(){
if(_backend == "localStorage" || _backend == "globalStorage"){
if("addEventListener" in window){
window.addEventListener("storage", _storageObserver, false);
}else{
document.attachEvent("onstorage", _storageObserver);
}
}else if(_backend == "userDataBehavior"){
setInterval(_storageObserver, 1000);
}
}
/**
* Fired on any kind of data change, needs to check if anything has
* really been changed
*/
function _storageObserver(){
var updateTime;
// cumulate change notifications with timeout
clearTimeout(_observer_timeout);
_observer_timeout = setTimeout(function(){
if(_backend == "localStorage" || _backend == "globalStorage"){
updateTime = _storage_service.jStorage_update;
}else if(_backend == "userDataBehavior"){
_storage_elm.load("jStorage");
try{
updateTime = _storage_elm.getAttribute("jStorage_update");
}catch(E5){}
}
if(updateTime && updateTime != _observer_update){
_observer_update = updateTime;
_checkUpdatedKeys();
}
}, 25);
}
/**
* Reloads the data and checks if any keys are changed
*/
function _checkUpdatedKeys(){
var oldCrc32List = JSON.parse(JSON.stringify(_storage.__jstorage_meta.CRC32)),
newCrc32List;
_reloadData();
newCrc32List = JSON.parse(JSON.stringify(_storage.__jstorage_meta.CRC32));
var key,
updated = [],
removed = [];
for(key in oldCrc32List){
if(oldCrc32List.hasOwnProperty(key)){
if(!newCrc32List[key]){
removed.push(key);
continue;
}
if(oldCrc32List[key] != newCrc32List[key]){
updated.push(key);
}
}
}
for(key in newCrc32List){
if(newCrc32List.hasOwnProperty(key)){
if(!oldCrc32List[key]){
updated.push(key);
}
}
}
_fireObservers(updated, "updated");
_fireObservers(removed, "deleted");
}
/**
* Fires observers for updated keys
*
* @param {Array|String} keys Array of key names or a key
* @param {String} action What happened with the value (updated, deleted, flushed)
*/
function _fireObservers(keys, action){
keys = [].concat(keys || []);
if(action == "flushed"){
keys = [];
for(var key in _observers){
if(_observers.hasOwnProperty(key)){
keys.push(key);
}
}
action = "deleted";
}
for(var i=0, len = keys.length; i<len; i++){
if(_observers[keys[i]]){
for(var j=0, jlen = _observers[keys[i]].length; j<jlen; j++){
_observers[keys[i]][j](keys[i], action);
}
}
}
}
/**
* Publishes key change to listeners
*/
function _publishChange(){
var updateTime = (+new Date()).toString();
if(_backend == "localStorage" || _backend == "globalStorage"){
_storage_service.jStorage_update = updateTime;
}else if(_backend == "userDataBehavior"){
_storage_elm.setAttribute("jStorage_update", updateTime);
_storage_elm.save("jStorage");
}
_storageObserver();
}
/**
* Loads the data from the storage based on the supported mechanism
*/
function _load_storage(){
/* if jStorage string is retrieved, then decode it */
if(_storage_service.jStorage){
try{
_storage = JSON.parse(String(_storage_service.jStorage));
}catch(E6){_storage_service.jStorage = "{}";}
}else{
_storage_service.jStorage = "{}";
}
_storage_size = _storage_service.jStorage?String(_storage_service.jStorage).length:0;
if(!_storage.__jstorage_meta){
_storage.__jstorage_meta = {};
}
if(!_storage.__jstorage_meta.CRC32){
_storage.__jstorage_meta.CRC32 = {};
}
}
/**
* This functions provides the "save" mechanism to store the jStorage object
*/
function _save(){
_dropOldEvents(); // remove expired events
try{
_storage_service.jStorage = JSON.stringify(_storage);
// If userData is used as the storage engine, additional
if(_storage_elm) {
_storage_elm.setAttribute("jStorage",_storage_service.jStorage);
_storage_elm.save("jStorage");
}
_storage_size = _storage_service.jStorage?String(_storage_service.jStorage).length:0;
}catch(E7){/* probably cache is full, nothing is saved this way*/}
}
/**
* Function checks if a key is set and is string or numberic
*
* @param {String} key Key name
*/
function _checkKey(key){
if(!key || (typeof key != "string" && typeof key != "number")){
throw new TypeError('Key name must be string or numeric');
}
if(key == "__jstorage_meta"){
throw new TypeError('Reserved key name');
}
return true;
}
/**
* Removes expired keys
*/
function _handleTTL(){
var curtime, i, TTL, CRC32, nextExpire = Infinity, changed = false, deleted = [];
clearTimeout(_ttl_timeout);
if(!_storage.__jstorage_meta || typeof _storage.__jstorage_meta.TTL != "object"){
// nothing to do here
return;
}
curtime = +new Date();
TTL = _storage.__jstorage_meta.TTL;
CRC32 = _storage.__jstorage_meta.CRC32;
for(i in TTL){
if(TTL.hasOwnProperty(i)){
if(TTL[i] <= curtime){
delete TTL[i];
delete CRC32[i];
delete _storage[i];
changed = true;
deleted.push(i);
}else if(TTL[i] < nextExpire){
nextExpire = TTL[i];
}
}
}
// set next check
if(nextExpire != Infinity){
_ttl_timeout = setTimeout(_handleTTL, nextExpire - curtime);
}
// save changes
if(changed){
_save();
_publishChange();
_fireObservers(deleted, "deleted");
}
}
/**
* Checks if there's any events on hold to be fired to listeners
*/
function _handlePubSub(){
if(!_storage.__jstorage_meta.PubSub){
return;
}
var pubelm,
_pubsubCurrent = _pubsub_last;
for(var i=len=_storage.__jstorage_meta.PubSub.length-1; i>=0; i--){
pubelm = _storage.__jstorage_meta.PubSub[i];
if(pubelm[0] > _pubsub_last){
_pubsubCurrent = pubelm[0];
_fireSubscribers(pubelm[1], pubelm[2]);
}
}
_pubsub_last = _pubsubCurrent;
}
/**
* Fires all subscriber listeners for a pubsub channel
*
* @param {String} channel Channel name
* @param {Mixed} payload Payload data to deliver
*/
function _fireSubscribers(channel, payload){
if(_pubsub_observers[channel]){
for(var i=0, len = _pubsub_observers[channel].length; i<len; i++){
// send immutable data that can't be modified by listeners
_pubsub_observers[channel][i](channel, JSON.parse(JSON.stringify(payload)));
}
}
}
/**
* Remove old events from the publish stream (at least 2sec old)
*/
function _dropOldEvents(){
if(!_storage.__jstorage_meta.PubSub){
return;
}
var retire = +new Date() - 2000;
for(var i=0, len = _storage.__jstorage_meta.PubSub.length; i<len; i++){
if(_storage.__jstorage_meta.PubSub[i][0] <= retire){
// deleteCount is needed for IE6
_storage.__jstorage_meta.PubSub.splice(i, _storage.__jstorage_meta.PubSub.length - i);
break;
}
}
if(!_storage.__jstorage_meta.PubSub.length){
delete _storage.__jstorage_meta.PubSub;
}
}
/**
* Publish payload to a channel
*
* @param {String} channel Channel name
* @param {Mixed} payload Payload to send to the subscribers
*/
function _publish(channel, payload){
if(!_storage.__jstorage_meta){
_storage.__jstorage_meta = {};
}
if(!_storage.__jstorage_meta.PubSub){
_storage.__jstorage_meta.PubSub = [];
}
_storage.__jstorage_meta.PubSub.unshift([+new Date, channel, payload]);
_save();
_publishChange();
}
/**
* CRC32 calculation based on http://noteslog.com/post/crc32-for-javascript/
*
* @param {String} str String to be hashed
* @param {Number} [crc] Last crc value in case of streams
*/
function _crc32(str, crc){
crc = crc || 0;
var n = 0, //a number between 0 and 255
x = 0; //an hex number
crc = crc ^ (-1);
for(var i = 0, len = str.length; i < len; i++){
n = (crc ^ str.charCodeAt(i)) & 0xFF;
x = "0x" + _crc32Table.substr(n * 9, 8);
crc = (crc >>> 8)^x;
}
return crc^(-1);
}
////////////////////////// PUBLIC INTERFACE /////////////////////////
$.jStorage = {
/* Version number */
version: JSTORAGE_VERSION,
/**
* Sets a key's value.
*
* @param {String} key Key to set. If this value is not set or not
* a string an exception is raised.
* @param {Mixed} value Value to set. This can be any value that is JSON
* compatible (Numbers, Strings, Objects etc.).
* @param {Object} [options] - possible options to use
* @param {Number} [options.TTL] - optional TTL value
* @return {Mixed} the used value
*/
set: function(key, value, options){
_checkKey(key);
options = options || {};
// undefined values are deleted automatically
if(typeof value == "undefined"){
this.deleteKey(key);
return value;
}
if(_XMLService.isXML(value)){
value = {_is_xml:true,xml:_XMLService.encode(value)};
}else if(typeof value == "function"){
return undefined; // functions can't be saved!
}else if(value && typeof value == "object"){
// clone the object before saving to _storage tree
value = JSON.parse(JSON.stringify(value));
}
_storage[key] = value;
_storage.__jstorage_meta.CRC32[key] = _crc32(JSON.stringify(value));
this.setTTL(key, options.TTL || 0); // also handles saving and _publishChange
_localStoragePolyfillSetKey(key, value);
_fireObservers(key, "updated");
return value;
},
/**
* Looks up a key in cache
*
* @param {String} key - Key to look up.
* @param {mixed} def - Default value to return, if key didn't exist.
* @return {Mixed} the key value, default value or null
*/
get: function(key, def){
_checkKey(key);
if(key in _storage){
if(_storage[key] && typeof _storage[key] == "object" &&
_storage[key]._is_xml &&
_storage[key]._is_xml){
return _XMLService.decode(_storage[key].xml);
}else{
return _storage[key];
}
}
return typeof(def) == 'undefined' ? null : def;
},
/**
* Deletes a key from cache.
*
* @param {String} key - Key to delete.
* @return {Boolean} true if key existed or false if it didn't
*/
deleteKey: function(key){
_checkKey(key);
if(key in _storage){
delete _storage[key];
// remove from TTL list
if(typeof _storage.__jstorage_meta.TTL == "object" &&
key in _storage.__jstorage_meta.TTL){
delete _storage.__jstorage_meta.TTL[key];
}
delete _storage.__jstorage_meta.CRC32[key];
_localStoragePolyfillSetKey(key, undefined);
_save();
_publishChange();
_fireObservers(key, "deleted");
return true;
}
return false;
},
/**
* Sets a TTL for a key, or remove it if ttl value is 0 or below
*
* @param {String} key - key to set the TTL for
* @param {Number} ttl - TTL timeout in milliseconds
* @return {Boolean} true if key existed or false if it didn't
*/
setTTL: function(key, ttl){
var curtime = +new Date();
_checkKey(key);
ttl = Number(ttl) || 0;
if(key in _storage){
if(!_storage.__jstorage_meta.TTL){
_storage.__jstorage_meta.TTL = {};
}
// Set TTL value for the key
if(ttl>0){
_storage.__jstorage_meta.TTL[key] = curtime + ttl;
}else{
delete _storage.__jstorage_meta.TTL[key];
}
_save();
_handleTTL();
_publishChange();
return true;
}
return false;
},
/**
* Gets remaining TTL (in milliseconds) for a key or 0 when no TTL has been set
*
* @param {String} key Key to check
* @return {Number} Remaining TTL in milliseconds
*/
getTTL: function(key){
var curtime = +new Date(), ttl;
_checkKey(key);
if(key in _storage && _storage.__jstorage_meta.TTL && _storage.__jstorage_meta.TTL[key]){
ttl = _storage.__jstorage_meta.TTL[key] - curtime;
return ttl || 0;
}
return 0;
},
/**
* Deletes everything in cache.
*
* @return {Boolean} Always true
*/
flush: function(){
_storage = {__jstorage_meta:{CRC32:{}}};
_createPolyfillStorage("local", true);
_save();
_publishChange();
_fireObservers(null, "flushed");
return true;
},
/**
* Returns a read-only copy of _storage
*
* @return {Object} Read-only copy of _storage
*/
storageObj: function(){
function F() {}
F.prototype = _storage;
return new F();
},
/**
* Returns an index of all used keys as an array
* ['key1', 'key2',..'keyN']
*
* @return {Array} Used keys
*/
index: function(){
var index = [], i;
for(i in _storage){
if(_storage.hasOwnProperty(i) && i != "__jstorage_meta"){
index.push(i);
}
}
return index;
},
/**
* How much space in bytes does the storage take?
*
* @return {Number} Storage size in chars (not the same as in bytes,
* since some chars may take several bytes)
*/
storageSize: function(){
return _storage_size;
},
/**
* Which backend is currently in use?
*
* @return {String} Backend name
*/
currentBackend: function(){
return _backend;
},
/**
* Test if storage is available
*
* @return {Boolean} True if storage can be used
*/
storageAvailable: function(){
return !!_backend;
},
/**
* Register change listeners
*
* @param {String} key Key name
* @param {Function} callback Function to run when the key changes
*/
listenKeyChange: function(key, callback){
_checkKey(key);
if(!_observers[key]){
_observers[key] = [];
}
_observers[key].push(callback);
},
/**
* Remove change listeners
*
* @param {String} key Key name to unregister listeners against
* @param {Function} [callback] If set, unregister the callback, if not - unregister all
*/
stopListening: function(key, callback){
_checkKey(key);
if(!_observers[key]){
return;
}
if(!callback){
delete _observers[key];
return;
}
for(var i = _observers[key].length - 1; i>=0; i--){
if(_observers[key][i] == callback){
_observers[key].splice(i,1);
}
}
},
/**
* Subscribe to a Publish/Subscribe event stream
*
* @param {String} channel Channel name
* @param {Function} callback Function to run when the something is published to the channel
*/
subscribe: function(channel, callback){
channel = (channel || "").toString();
if(!channel){
throw new TypeError('Channel not defined');
}
if(!_pubsub_observers[channel]){
_pubsub_observers[channel] = [];
}
_pubsub_observers[channel].push(callback);
},
/**
* Publish data to an event stream
*
* @param {String} channel Channel name
* @param {Mixed} payload Payload to deliver
*/
publish: function(channel, payload){
channel = (channel || "").toString();
if(!channel){
throw new TypeError('Channel not defined');
}
_publish(channel, payload);
},
/**
* Reloads the data from browser storage
*/
reInit: function(){
_reloadData();
}
};
// Initialize jStorage
_init();
})();