zowie
Version:
Simple API for HTML5 Local Storage
230 lines (209 loc) • 6.76 kB
JavaScript
// The MIT License (MIT)
//
// Copyright (c) 2015-Eternity Gerry Gold & Vera
//
// 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.
//
// @author gerry.gold@gmail.com
//
// MIT License
//
// How to Write and Read Using Browser's localStorage (ES6 Syntax):
//
// import Zowie from 'zowie';
// const Cache = new Zowie();
//
// Cache.put('myKey', {data: {x: 1, y: 2, z: 3}});
// const data = Cache.get('myKey');
'use strict';
Object.defineProperty(exports, "__esModule", {
value: true
});
var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
var Zowie = function () {
function Zowie() {
var isPersistent = arguments.length <= 0 || arguments[0] === undefined ? true : arguments[0];
_classCallCheck(this, Zowie);
this.persistent = isPersistent;
this._lootBag = {};
// By default there is no timeout
this._timeout = null;
}
_createClass(Zowie, [{
key: 'put',
value: function put(key, val) {
var item = { v: val, t: this._getNow() };
if (this.persistent) {
localStorage.setItem(key, JSON.stringify(item));
} else {
this._lootBag[key] = item;
}
}
// If key does not exist:
// if 2nd arg is passed, i.e., default is defined, return default
// if 2nd arg is not passed, return null
}, {
key: 'get',
value: function get(key) {
var default_value = arguments.length <= 1 || arguments[1] === undefined ? null : arguments[1];
if (this.persistent) {
// local storage
if (key in localStorage) {
var obj = JSON.parse(localStorage.getItem(key));
if (this._timeout === null) {
return obj.v;
} else {
if (this._isCacheStale(obj.t)) {
this.removeKey(key);
return default_value;
} else {
return obj.v;
}
}
} else {
return default_value;
}
} else {
// in memory
if (key in this._lootBag) {
if (this._timeout === null) {
return this._lootBag[key].v;
} else {
if (this._isCacheStale(this._lootBag[key].t)) {
this.removeKey(key);
return default_value;
} else {
return this._lootBag[key].v;
}
}
} else {
return default_value;
}
}
} // end get()
// If a TTL is set and the key has expired, its existence is set free. :)
}, {
key: 'keyExists',
value: function keyExists(key) {
if (this.persistent) {
// local storage
if (key in localStorage) {
if (this._timeout === null) {
return true;
} else {
var obj = JSON.parse(localStorage.getItem(key));
if (this._isCacheStale(obj.t)) {
this.removeKey(key);
return false;
} else {
return true;
}
}
} else {
return false;
}
} else {
// in memory
if (key in this._lootBag) {
if (this._timeout === null) {
return true;
} else {
if (this._isCacheStale(this._lootBag[key].t)) {
this.removeKey(key);
return false;
} else {
return true;
}
}
} else {
return false;
}
}
} // end keyExists
}, {
key: 'removeKey',
value: function removeKey(key) {
if (this.persistent) {
if (key in localStorage) {
localStorage.removeItem(key);
}
} else {
if (key in this._lootBag) {
delete this._lootBag[key];
}
}
}
}, {
key: 'clear',
value: function clear() {
if (this.persistent) {
localStorage.clear();
} else {
this._lootBag = {};
}
}
}, {
key: 'keys',
value: function keys() {
return this.persistent ? Object.keys(localStorage) : Object.keys(this._lootBag);
}
}, {
key: 'isLocalStorageAvailable',
value: function isLocalStorageAvailable() {
var key = new Date().getTime().toString();
var val = key;
try {
localStorage.setItem(key, val);
localStorage.removeItem(key);
return true;
} catch (ex) {
return false;
}
}
}, {
key: '_getNow',
value: function _getNow() {
return parseInt(Date.now() / 1000, 10);
}
}, {
key: '_isCacheStale',
value: function _isCacheStale(timestamp) {
return this._getNow() - timestamp > this._timeout;
}
}, {
key: 'timeoutInSeconds',
set: function set(timeInSeconds) {
this._timeout = timeInSeconds;
},
get: function get() {
return this._timeout;
}
}, {
key: 'persistent',
get: function get() {
return this._persistent;
},
set: function set(isPersistent) {
this._persistent = isPersistent;
}
}]);
return Zowie;
}();
exports.default = Zowie;