Ember (also known as Ember.js) is a comprehensive JavaScript front-end framework that gives you everything you need to design and develop modern web applications. If you’re looking for a framework that strikes a unique balance between scalability, backwards compatibility, and experimentation, Ember may be the framework for you.

Read on to learn more about Ember.js and its role in the world of front-end web development.

THE EMBER WAY

Ember has come a long way since its initial release in December 2011, when the successor to the popular widget library SproutCore forked off into a separate project to create a full-featured framework for building scalable dynamic single page applications (SPAs). Today Ember.js powers prominent websites like LinkedIn, Groupon, and Twitch TV, and desktop apps like Apple Music. Some of the core themes that Ember embraces include:

  • “Convention over Configuration,” a concept popularized by Ruby on Rails, Ember encourages the use of bootstrapping a new project through its CLI to ensure that best practices are being followed and help developers get a head start on their projects
  • “Stability without Stagnation,” by making continuous incremental improvements to the framework across 6 week release cycles, preceding major updates with deprecation warnings, and maintaining a rigorous RFC (Request for Comment) process, major upgrades (like the switch to 2.0) go much smoother.
  • A proven commitment toward backwards compatibility (Ember 2.0 still supports Internet Explorer 9 at the time of this writing).
  • A more robust built-in router system
  • Early adoption of the latest JavaScript and web standards (i.e. ES6, Web Components)
  • A complete solution to solving the problem of creating “ambitious web applications”

With the release of Ember 2.0, Ember made some changes to keep up with the components-based future of web development:

  • Glimmer, a blazingly fast rendering engine that evolved into a standalone, lightweight UI components library
  • “Data down, actions up” (one way data flow by default)
  • Standard lifecycle hooks for components

In true Ember fashion, many “2.0” improvements were actually started in earlier versions, like the powerful Glimmer 1 rendering engine which shipped in 1.13.

EMBER CLI

Many languages and frameworks have CLIs, but few are as robust or central to a technology stack as the Ember CLI. To keep its promise to favor “convention over configuration,” Ember’s command line utility allows you to generate a new app with a few simple commands to instantly get:

  • The latest approved file directory structure
  • A complete testing framework
  • A development server with live preview
  • The latest JavaScript modules and syntax support with Babel (i.e. ES6/ES7 at the time of this writing)
  • Dependencies managed via Bower and NPM
  • Blueprints (both built-in and custom) for creating models, controllers, components and other parts of an application
  • Asset management support for things like minification, version control, and combining
  • Add-ons that extend the functionality of the Ember CLI (like LESS, Sass, and CoffeeScript).

When best practices are updated, those updates can easily be flowed down to the community at large via the CLI. Better still, Ember has a dedicated team that tries to make updating existing projects as easy as possible, and automates changes through the CLI where possible.

ROUTING

From its inception, Ember differentiated itself from other frameworks by placing routers front and center:

“Nowadays, routers are taken for granted. Every framework, every library has a router that you can drop into it. But there was actually some novel computer science work that went into it, in how we tie the architecture of the app to the URL. That took a long time and it was a very organic process. I don’t think we fully understood the magnitude of the research project that was going on. There are a lot of examples of that where we tackled problems for the first time, so of course, there’s gonna be kind of an organic exploration of that space.”

-Tom Dale, Ember co-founder at EmberConf 2017

In Ember, application state is driven directly from the URL, and much of an Ember app’s structure is centered around how you set a URL in response to a user interaction.

TEMPLATING ENGINE

Ember uses the popular Handlebars templating library as its templating engine. Handlebars templates are characterized by the use of static HTML with dynamic content via Handlebars expressions invoked with the double curly braces: {{}}. Handlebar expressions are backed by a “context,” an object that provides the properties used by the expression. In Ember this “context” is often a component.

EMBER DATA

Ember provides its own solution for ORM (Object-Relational Mapping) with Ember Data. In most web applications, models (the objects that represent the underlying data that your application presents to the user) are stored in a database on a server. If a user were to access something like their shopping cart, they might expect the items they put in there to remain, even after they’ve closed their browser or logged out of their account. This expectation for models to remain “persistent” is part of model management that is typically addressed on the server-side. What Ember Data does is give you an adaptive data layer that allows you to swap database technologies without having to rewrite anything on the front-end.

Whether you are using JSON APIs over HTTP, streaming content with WebSockets, or using local IndexedDB storage, your API is agnostic to the persistent data storage solution you choose to use, insulating it from most major changes to the back-end. Configuring Ember Data to work with a large variety of back-ends is as simple as picking the right adapter.

Besides adapters, another important part of Ember Data is the use of a store as a “single source of truth,” a key concept that continues to turn up in frameworks that have embraced components-based web development. To avoid the scenario where two or more components make two or more separate requests for the same information, Ember Data provides a single repository of all the models within an application that components and routes can query. The store handles the actual fetching from the server. In the event that two or more components or routes ask for the same model, the store will only retrieve data from the server once, saving bandwidth and avoiding bugs.

There is a bit of a learning curve to using Ember Data, especially if you’re more used to working with AJAX to retrieve raw JSON data from a server. However it is worth mentioning that managing application state and maintaining your codebase as your app scales is much easier with something like Ember Data working behind the scenes to ensure your models remain persistent and your code is well encapsulated. You don’t have to use Ember Data, but most Ember applications use it as their go-to data persistence library of choice by default when you create a new app with the Ember CLI.

EMBER INSPECTOR

Looking for a browser add-on to help you read, and debug your Ember apps in real-time? Ember.js already has you covered with Ember Inspector, browser extension that does just that. Ember Inspector allows you to view and edit your Ember Data models, routes, controllers, templates, and components, with live updates in your browser.

SHOULD YOU USE EMBER FOR YOUR PROJECT?

Ember is a powerful JavaScript framework that gives you everything you need to build scalable SPAs. Where Ember really stands is its ability to push the boundaries of front-end web development without leaving anyone behind. A tight knit community with great communication between the core Ember development team and the developer community at large ensures developers have time and warning to incrementally upgrade their projects with the framework and avoid potentially app breaking changes.

Consider using Ember if…

  • You prize “convention over configuration” and want a top-tier CLI that lets you easily bootstrap new projects with the latest best practices
  • You’re looking for a framework that stays up to date with the latest versions of JavaScript (ES6/ES7 via Babel).
  • You’re looking for backwards compatibility and long-term stability
  • You’re looking for a thriving community with thousands of addons (4,000+)
  • You’re looking for a framework that does it all (from MVC to components based web development)
  • You embrace the componentized future of web development.

This article barely scratched the surface of the Ember ecosystem—from the ability to use server-side rendering with FastBoot, to the new standalone UI component library Glimmer 2, the Ember community is always cooking up new things for the developer community to enjoy.