An abstraction layer for working with localStorage

datastore.js

/**
 * localStorage abstraction
 * Get and Set JS Objects in localStorage
 * 
 * This is meant for really simple localStorage needs, not to replace
 * anything like Backbone.localStorage that's more robust. A good
 * use-case is storing an array of IDs for models that are stored on
 * the server.
 * 
 * Usage:
 * 
 *   var myStore = new dataStore('storageName');
 *   // >> dataStore {name: "storageName", fetch: function, set: function}
 *   myStore.set({someKey : "This will be stored as JSON"});
 *   // >> undefined
 *   myStore.fetch();
 *   // >> Object {someKey : "This will be stored as JSON"}
 *   localStorage.getItem('storageName');
 *   // >> "{"someKey":"This will be stored as JSON"}"
 * 
 */

var DataStore = (function () {

  /**
   * Constructor. Takes a name and optional second value, which will be set in
   * to the data store using the `set` method.
   * 
   * @param name {String} string to use as the key for storing the data in
   *                      localStorage
   * @param data (optional) can be any valid JavaScript object, will get stored
   *             in the `name`d location in localStorage
   **/
  var dataStore = function(name){
    this.name = name;
    if (data) { this.set(data); }
  };

  dataStore.prototype = {
    /**
     * Getter method; retrieves the data stored under the dataStore's name from
     * localStorage, then parses it with JSON.parse
     *
     * @method fetch
     * @param none
     * @returns object
     **/
    fetch : function () {
      return JSON.parse(localStorage.getItem(this.name));
    },

    /**
     * Setter method; takes a JavaScript object, runs it through JSON
     * stringify, and then stores it in localStorage under the dataStore's name
     *
     * @method set
     * @param obj {Object} Can be any valid JavaScript object -- whether that's an object or a string. Should be something that can be parsed by JSON.stringify
     * @returns undefined
     **/
    set : function (obj) {
      localStorage.setItem(this.name, JSON.stringify(obj));
    }
  };

  return dataStore;
})();