Ember.js

Ember.js

Ember.js logo
Developer(s)	Yehuda Katz, Tom Dale and Ember.js contributors
Initial release	2011 (2011)
Stable release	1.11.3 / April 14, 2015 (2015-04-14)
Repository	github.com/emberjs/ember.js
Written in	JavaScript
Operating system	Cross-platform
License	MIT License
Website	emberjs.com

Ember.js is an open-source client-side JavaScript web application framework based on the model-view-controller (MVC) software architectural pattern. It allows developers to create scalable single-page applications by incorporating common idioms and best practices into a framework that provides a rich object model, declarative two-way data binding, computed properties, automatically-updating templates powered by its own template library, HTMLBars (previously Handlebars.js), and a router for managing application state.

Basic Concepts

Routes

The router is a core concept of Ember, emphasizing the importance of the URL in managing application state. A route object corresponds to a URL and essentially serializes the application's current state. Routes are defined in the singleton Router object.

Models

Every route has an associated model, containing the data associated with the current state of the application. While one can use jQuery to load JSON objects from a server and use those objects as models, most applications use a model library such as Ember Data to handle this.

Controllers

Controllers are used to decorate models with display logic. It was typical for a controller to inherit from ObjectController if the template was associated with a single model record and ArrayController if the template was associated with a list of records. However, ObjectController and ArrayController have been deprecated in favor of explicitly accessing of the model property of Ember.Controller.

Templates

Templates are written with the HTMLBars templating language (a variation on the Handlebars template system) to describe the user interface. Templates are used to build the application's HTML and embed dynamically-updating expressions.

Views

Views are used to add sophisticated handling of user events, custom graphics not made with CSS, JavaScript animations, or reusable behavior to a template.

Components

Components are a specialized view for creating custom elements that can be easily reused in templates. The Ember Components implementation conforms as closely as possible to the W3C Web Components specification.

Ember Data

Most Ember.js applications use Ember Data, a data persistence library that maps client-side models to server-side data, although it is also possible to use Ember.js without Ember Data. By default, Ember Data can load and save records and their relationships without any configuration via a RESTful JSON API that follows certain conventions, providing many of the facilities of an ORM, but it is also easily configurable and can work with any server through the use of adapters. Ember Data is currently in beta and its API should not be considered stable until version 1.0.

Ember Inspector

The Ember Inspector is an extension currently available for the Mozilla Firefox and Google Chrome web browsers that claims to make debugging Ember applications easier. Features include the ability to see which templates, controllers and models are currently rendered, see the properties of any Ember object with a UI that computes bindings and computed properties, and use the $E variable to access your application's objects from the console. If Ember Data is used, one can also see the records loaded for each model.

Ember CLI

The ember-cli command line utility is a build tool for Ember.js based on broccoli. Features include ECMAScript 6 module syntax, dependency management through bower and npm, generators based on blueprints, and the ability of third parties to extend it via addons. Ember CLI replaces the deprecated Ember App Kit.

History

In December 2011, the SproutCore 2.0 framework was renamed to Ember.js, to reduce confusion between the application framework and the widget library of SproutCore 1.0. The framework was created by Yehuda Katz, a member of the jQuery, Ruby on Rails and SproutCore core teams. Like many of Katz's other projects, it advocates for convention over configuration.