Simple Application Store

app-store.js

/**
 * A simple app store utilizing localStorage.
 */

/**
 * Initialize the store.
 */
application = application || {};
application.store = {};

/**
 * Update or create a stored setting.
 *
 * @param {string} key
 * @param {string} value
 * @returns {undefined}
 */
application.store.put = function(key, value) {
  // both key and value must be non-null in order to set var in local storage
  if (key && value) {
    window.localStorage.setItem(key, value);
  }
}

/**
 * Update or create a stored setting. Converts value into JSON.
 *
 * @param {string} key
 * @param {mixed} value
 * @returns {undefined}
 */
application.store.putJson = function(key, value) {
  // both key and value must be non-null in order to set var in local storage
  if (key && value) {
    application.store.put(key, JSON.stringify(value));
  }
}

/**
 * Get a stored setting.
 *
 * @param {string} key
 * @returns {string}
 */
application.store.get = function(key) {
  // if for some reason there is a var in local storage with NaN value, just return null instead
  var item = window.localStorage.getItem(key);
  if (
    item === undefined ||
    item === null ||
    (!item && isNaN(item))
  ) {
    return null;
  }
  return item;
}

/**
 * Get a stored setting. Automatically parse JSON.
 *
 * @param {string} key
 * @returns {string}
 */
application.store.getJson = function(key) {
  // if for some reason there is a var in local storage with NaN value, just return null instead
  var item = window.localStorage.getItem(key);
  if (
    item === undefined ||
    item === null ||
    (!item && isNaN(item))
  ) {
    return null;
  }
  return JSON.parse(item);
}

/**
 * Delete a stored setting.
 *
 * @param {string} key
 * @returns {unknown}
 */
application.store.remove = function(key) {
  return window.localStorage.removeItem(key);
}

/**
 * Delete the entire store.
 *
 * @returns {undefined}
 */
application.store.clear = function() {
  window.localStorage.clear();
}