rarwe.tar.gz

Ember

Ember-copy

ember2

embercss

rarwe

Ember-copy-5yvdqv

Ember-copy-5yvdqv-copy

Ember-Acceptest

Ember-Acceptest-copy

Ember-unitest

rarwe-copy

Ember-Acceptest-challenge

Ember-helper-challenge

In this course, you begin with an introduction to Ember.js, a JavaScript framework for building client-side applications.

After that, the course guides you through the steps of building a real application so that you can see how the concepts are applied in practice. You'll learn about the building blocks of Ember one by one, in a way that crushes the allegedly steep learning curve of the framework.

The application will get shinier (and/or more robust) with each chapter. By the end, we will have a decent app, and you'll have a great new skill you can add to your resume.

Developing Robust Ember.js Applications

We have a nifty catalog that handles our data operations and keeps copies of the records on the backend, like a cache, if you will. That said, it’s far from finished. Is code ever finished, though? There are loads of things we could add or change to improve it. Here is a list of things we thought of:

* Collections should be hashes, like POJOs, or Maps for quicker look-up.
* Some refactoring would be valuable to have fewer conditional branches based on type. A lot of the methods can only deal with `bands` and `songs` and are not prepared for other model types.
* `add` could return the record just added, or already found, in the catalog
* This is not strictly for the catalog, but we could enhance our model classes with a `save` method that would call the current `update` method of the catalog. Instead of writing `catalog.update('song', song, attributes)`, we could  write `song.save(attributes)`. This greatly improves developer ergonomics.
* We could add `fetch` to complement `fetchAll`. We don't need to query a single record from the back-end in the current state of the app because by the time we enter the `bands.band` route we can be sure to have fetched all the band records from the backend, so we can just look up the one we need from the catalog. However, in most applications, the need to fetch a single record is very common.
* Reverse relationships are not automatically updated. If we call `catalog.fetchRelated(band, 'songs')`, we know that each song's `band` relationship should be set to `band`, but this is not done.
* Similarly, when we save a song to the backend where the `band` relationship is set, the `songs` relationship with the band could be updated automatically to include the song.


# What about Ember Data?

You might have heard about the standard data library for Ember, **Ember Data (ED)**. It is a mature project, almost as old as Ember.js itself and implements what we have in the `catalog` service and a whole lot more.

The reason we haven't started using it right off-the-bat is that we wanted to demonstrate that it's perfectly possible to build an app without Ember Data. It is a common misconception that you need to use Ember Data with Ember, in part because it comes installed with new Ember projects.

The more complex your app’s data scenarios, the more sense it makes to use ED. Because it’s an “in-house” project and not a third party add-on, it’s quite well maintained and developed, so you might decide to adopt it from the start. Possibly the only drawback of this decision is its size. Removing the package from the project reduced both the compressed and uncompressed vendor build by about 20%, the uncompressed size being reduced by 164kb. This can be substantial in some apps.

The Ember Data team is well aware of the all-or-nothing nature of the project and have launched Project Trim. Its goal is to decompose it to smaller packages that each implement a specific feature set, including models, relationships, etc. so that only the required parts need to be installed.

Since we aren’t currently using the Ember-Data package, let’s go ahead and remove it:
```shell
npm uninstall ember-data
```

>**Note**: We have already deleted the Ember Data, but you can also try the above command in the terminal below.

Let’s talk about things to add, change, delete, and improve in our app.

Are We There Yet?