localstorage-05.js

var ls = require('lib/LocalStorage');
// These examples assume you are using jQuery for AJAX calls.

// Closure usage
ls.getItem('devices', function(devices) {
   if (devices === null) {
       $.ajax({
           url: '/data/devices.json',
           dataType: 'json',
           method: 'get'
       }).done(function (data, textStatus, jqXHR) {
           if (jqXHR.status == 200) {
               // Cache response in localStorage for 1 hour.
               ls.setItem('devices', data.devices, 3600);

               anotherFunction(data.devices);
           }
       });
   } else {
       anotherFunction(devices);
   }
});

// Variable assignment
var devices = ls.getItem('devices', function(devices) {
   if (devices === null) {
       $.ajax({
           url: '/data/devices.json',
           dataType: 'json',
           method: 'get'
       }).done(function (data, textStatus, jqXHR) {
           if (jqXHR.status == 200) {
               // Cache response in localStorage for 1 hour.
               ls.setItem('devices', data.devices, 3600);

               return data.devices;
           }
       });
   } else {
       return devices;
   }
});

doSomething(devices);