Modeling Leads

To handle data we’ll be using Ember Data. We already installed it in Hello World so we don’t have do anything to start using it. Although there are a few different data adapters for Ember, Ember Data is the standard.

We have a Lead model in Rails but Ember needs to know about leads too. To do that we’ll create a lead model in Ember. Ember Data gives us the DS.Model object which we’ll extend:

# app/assets/javascripts/models/lead.js.coffee
App.Lead = DS.Model.extend
  firstName: DS.attr('string')
  lastName: DS.attr('string')
  email: DS.attr('string')
  phone: DS.attr('string')
  status: DS.attr('string', defaultValue: 'new')
  notes: DS.attr('string')

// app/assets/javascripts/models/lead.js
App.Lead = DS.Model.extend({
  firstName: DS.attr('string'),
  lastName: DS.attr('string'),
  email: DS.attr('string'),
  phone: DS.attr('string'),
  status: DS.attr('string', { defaultValue: 'new' }),
  notes: DS.attr('string'),
})

Ember will automatically read in the json api’s first_name to firstName, and etc. across the rest of our attributes. We’re only using the string data type here. The other ones available to you are number, boolean, and date.

An Aside about DS.Model

DS.Model gives you a variety of useful methods and properties. Here are a few methods that you will use often:

model.save() # save changes to the database
model.rollback() # wipe clean any unsaved changes
model.destroyRecord() # delete a record from the database

model.save() // save changes to the database
model.rollback() // wipe clean any unsaved changes
model.destroyRecord() // delete a record from the database

Note that DS.Model extends Ember.Object, so all of the things you learned about Ember Objects will still work with DS.Model. For example, you can set an arbitrary property on a DS.Model instance like so:

model.set('myProperty', 'hello!')

model.set('myProperty', 'hello!');

The main difference between DS.Model instances and regular Ember.Object instances is that you cannot create them the same way. To create a new DS.Model instance you have to go through the store:

@store.createRecord('modelName', firstName: 'John', lastName: 'Snow')

this.store.createRecord('modelName', { firstName: 'John', lastName: 'Snow' });

This is because the store encapsulates your app’s knowledge of all the active DS.Model instances, and the store has to do additional work when you create a model instance.