Basically, this is the same as using any other structure with Ember.js, sorta. The problem is that Codeigniter does not have built-in ORMs or good PDO drivers. Since it has not changed for many years, and it still uses the old version of PHP, it can be difficult for you. There were some improvements to the PHP library section using Composer (although it is insanely slow). You can use some of the most popular ORMs, such as Laravel Eloquent.
A few searches will bring this lesson up: http://mannyisles.com/using-eloquent-orm-inside-codeigniter.html
JSON, API. Ember Data. Ember Data API RESTful. , . , RESTful.
. . , , :
Ember, codeigniter. , Laravel 4, JSON API. Codeigniter.