From the beginning Ember was designed around several key ideas: ; Focus on ambitious web applications ; More productive out of the box ; Stability without stagnation ; Future web standards foresight Like Ruby on Rails, Ember follows Convention over Configuration, and the Don't Repeat Yourself principle. It has been described as a highly opinionated framework built to be very flexible.
Basic concepts
Ember consists of five key concepts: ; Routes ; Models ; Templates ; Components ; Services Ember also provides dependency injection, declarative two-way data binding, computed properties, and automatically-updating templates.
Ember 2.0
Ember 2.0 was released August 13, 2015. The guiding principles for the release were simplification and stability without stagnation. The biggest changes occur in the view layer and include:
Another major change was the introduction of the Glimmer rendering engine with the aim of improving re-render performance. Glimmer adopts a value-diffing strategy, using a virtual tree of the dynamic areas of the document object model, similar to React. A number of benchmarks illustrating the speedup in performance have been published. Since version 1.8 new features identified for 2.0 have been shipped when ready on the 1.x branch, while still maintaining backward compatibility. Features due to be removed in 2.0 have been deprecated. This means that 1.13 contains virtually all 2.0 changes, with 2.0 mainly being about removing deprecated features from the code base. In many cases the removed code is still available in addons.
Ember software stack
Ember.js is one component of a complete front end stack built and supported by the Ember core team.
Development server with live reload. Out of the box this will automatically rebuild apps incrementally whenever files are changed, and then reload the app in any open browser tabs.
Blueprints, which are code generators for creating models, controllers, components, and so on that are needed in an application. Custom blueprints can also be created.
Addons which provide the ability to extend the features of Ember CLI. Addons can be installed by typing ember install . Over two thousand addons are currently available including addons for CoffeeScript, LESS, Sass, Compass and Mocha.
Ember Data
Most Ember applications use Ember Data, a data-persistence library providing many of the facilities of an object-relational mapping. However it is also possible to use Ember without Ember Data. Ember Data maps client-side models to server-side data. It can then load and save records and their relationships without any configuration via a RESTful JSON API that implements the JSON API specification, provided certain conventions are followed. However it is also easily configurable and can work with any server through the use of adapters and addons. JSON API has server library implementations for PHP, Node.js, Ruby, Python, Go,.NET and Java. Connecting to a Java-Spring based server is also documented. The first stable version of Ember Data was released on 18 June 2015.
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, components, and views are currently rendered, see the properties of any Ember object with a UI that computes bindings and computed properties, and access your application's objects from the console. If Ember Data is used, one can also see the records loaded for each model.
The Object Inspector allows you to view and edit the runtime contents of Ember Objects and Classes.
The View Tree visually displays the structure of the rendered Ember application.
The Routes tab allows one to determine and follow the router state and the urls used to represent routes.
The Data tab can show you the models in your application and records loaded for each model.
The Info tab displays versions of your dependencies.
The Deprecations tab allows for getting stacktraces of deprecation warnings that do not trigger exceptions.
The Promises tab allows for tracing of code through asynchronous operations.
The Container tab is useful for checking which objects have been loaded.
The Render Performance tab is for determining what is slowing down your Ember application.
Fastboot
Fastboot is an Ember CLI addon created by the Ember core team that gives Ember developers the ability to run their apps in Node.js. This feature allow end users to see HTML and CSS right away, with the JavaScript downloading in the background and taking over once it has fully loaded.
Liquid Fire
Liquid Fire provides animation support for Ember applications. Features include animated transitions between routes and between models within a single route. It provides a DSL for laying out spatial route relationships, cleanly separated from view-layer implementation details. A simple example would be to animate a screen transition, so that the new screen appears to slide in from one edge of the browser.
Release process
Release cycle
Ember follows a six-week release cycle, inspired by the rapid release cycle of Google Chrome. Every six weeks a new release is made available, and at the same time a beta for the next release is also published. Generally several betas are produced before the next major release comes round, roughly one beta per week. Starting with Ember 2.0, related projects supported by the core team have their releases coordinated, and share a version number with Ember itself.
Upgrading and backward compatibility
Ember follows the semantic versioning convention. In particular this means that breaking changes are only introduced at major version numbers such as 1.0, 2.0 etc. While new features can be added at point releases, and features deprecated, no breaking changes to the public API's are introduced and upgrading within a major version is designed to be as simple as possible. Tooling is also under development to help streamline the upgrade process. In addition to this process a number of steps were taken to mitigate issues around upgrading to the 2.0 release:
All major 2.0 features were in fact introduced early and spread out over a number of releases in order to reduce many of the issues caused by big-bang upgrades.
Most features that were removed are still available through addons.
The process follows the core Ember principle of Stability without Stagnation and is in marked contrast to the upgrade plans of similar projects such as AngularJS.
Future development
Project status can be tracked via the core team meeting minutes. However major changes to Ember go through the Request For Comment process. This gives the Ember community a chance to give feedback on new proposals. Notable RFCs include:
Engines. Engines allow multiple logical applications to be composed together into a single application from the user's perspective. Currently released as an experimental addon.
Release cycle improvements. Among other things it proposes changes to Ember CLI to support "svelte builds", which will strip out deprecated and unused features.
Outlet Focusing. Making Ember accessible by default. This RFC aims to improves the user experience for people using screen readers.
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 convention over configuration.
Legacy browser support
Support for Internet Explorer 8 is available up to version 1.13, but will be dropped from release 2.0 onwards. Internet Explorer 9 and later will continue to be supported. The core team will continue to periodically publish point releases in the 1.13 series to patch security bugs and browser compatibility issues, including issues in IE8.
Corporate sponsorship
Unlike other projects such as AngularJS and React which have the backing of one main company, Emberjs has a variety of sponsors. These include Yahoo!, LinkedIn and Bustle which are all major users of the framework.
