/*
* ----------------------------- JSTORAGE -------------------------------------
* Simple local storage wrapper to save data on the browser side, supporting
* all major browsers - IE6+, Firefox2+, Safari4+, Chrome4+ and Opera 10.5+
*
* Author: Andris Reinman, andris.reinman@gmail.com
* Project homepage: www.jstorage.info
*
* Licensed under Unlicense:
*
* This is free and unencumbered software released into the public domain.
*
* Anyone is free to copy, modify, publish, use, compile, sell, or
* distribute this software, either in source code form or as a compiled
* binary, for any purpose, commercial or non-commercial, and by any
* means.
*
* In jurisdictions that recognize copyright laws, the author or authors
* of this software dedicate any and all copyright interest in the
* software to the public domain. We make this dedication for the benefit
* of the public at large and to the detriment of our heirs and
* successors. We intend this dedication to be an overt act of
* relinquishment in perpetuity of all present and future rights to this
* software under copyright law.
*
* 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 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.
*
* For more information, please refer to
*/
(function(){
var
/* jStorage version */
JSTORAGE_VERSION = "0.4.7",
/* 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(!("parse" in JSON) || !("stringify" in JSON)){
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 = {__jstorage_meta:{CRC32:{}}},
/* 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,
/**
* 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;
}
};
////////////////////////// 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) {
if(window.location.hostname == "localhost"){
_storage_service = window.globalStorage["localhost.localdomain"];
}
else{
_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();
// 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);
}
}
/**
* 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] && String(oldCrc32List[key]).substr(0,2) == "2."){
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=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; iGary Court
* @see http://github.com/garycourt/murmurhash-js
* @author Austin Appleby
* @see http://sites.google.com/site/murmurhash/
*
* @param {string} str ASCII only
* @param {number} seed Positive integer only
* @return {number} 32-bit positive integer hash
*/
function murmurhash2_32_gc(str, seed) {
var
l = str.length,
h = seed ^ l,
i = 0,
k;
while (l >= 4) {
k =
((str.charCodeAt(i) & 0xff)) |
((str.charCodeAt(++i) & 0xff) << 8) |
((str.charCodeAt(++i) & 0xff) << 16) |
((str.charCodeAt(++i) & 0xff) << 24);
k = (((k & 0xffff) * 0x5bd1e995) + ((((k >>> 16) * 0x5bd1e995) & 0xffff) << 16));
k ^= k >>> 24;
k = (((k & 0xffff) * 0x5bd1e995) + ((((k >>> 16) * 0x5bd1e995) & 0xffff) << 16));
h = (((h & 0xffff) * 0x5bd1e995) + ((((h >>> 16) * 0x5bd1e995) & 0xffff) << 16)) ^ k;
l -= 4;
++i;
}
switch (l) {
case 3: h ^= (str.charCodeAt(i + 2) & 0xff) << 16;
case 2: h ^= (str.charCodeAt(i + 1) & 0xff) << 8;
case 1: h ^= (str.charCodeAt(i) & 0xff);
h = (((h & 0xffff) * 0x5bd1e995) + ((((h >>> 16) * 0x5bd1e995) & 0xffff) << 16));
}
h ^= h >>> 13;
h = (((h & 0xffff) * 0x5bd1e995) + ((((h >>> 16) * 0x5bd1e995) & 0xffff) << 16));
h ^= h >>> 15;
return h >>> 0;
}
////////////////////////// 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] = "2." + murmurhash2_32_gc(JSON.stringify(value), 0x9747b28c);
this.setTTL(key, options.TTL || 0); // also handles saving and _publishChange
_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) {
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];
_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:{}}};
_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();
},
/**
* Removes reference from global objects and saves it as jStorage
*
* @param {Boolean} option if needed to save object as simple "jStorage" in windows context
*/
noConflict: function( saveInGlobal ) {
delete window.$.jStorage
if ( saveInGlobal ) {
window.jStorage = this;
}
return this;
}
};
// Initialize jStorage
_init();
})();