EmberJS：如何在同一路线上加载多个模型？

Question

While I am not new to web development, I am quite new to to client-side MVC frameworks. I did some research and decided to give it a go with EmberJS. I went through the TodoMVC guide and it made sense to me...

I have setup a very basic app; index route, two models and one template. I have a server-side php script running that returns some db rows.

One thing that is very confusing me is how to load multiple models on the same route. I have read some information about using a setupController but I am still unclear. In my template I have two tables that I am trying to load with unrelated db rows. In a more traditional web app I would have just issued to sql statements and looped over them to fill the rows. I am having difficulty translating this concept to EmberJS.

How do I load multiple models of unrelated data on the same route?

I am using the latest Ember and Ember Data libs.

Update

although the first answer gives a method for handling it, the second answer explains when it's appropriate and the different methods for when it isn't appropriate.

Answer 1

BEWARE:

You want to be careful about whether or not returning multiple models in your model hook is appropriate. Ask yourself this simple question:

1. Does my route load dynamic data based on the url using a slug :id ? ie this.resource('foo', {path: ':id'});

If you answered yes

Do not attempt to load multiple models from the model hook in that route!!! The reason lies in the way Ember handles linking to routes. If you provide a model when linking to that route ( {{link-to 'foo' model}} , transitionTo('foo', model) ) it will skip the model hook and use the supplied model. This is probably problematic since you expected multiple models, but only one model would be delivered. Here's an alternative:

Do it in setupController / afterModel

App.IndexRoute = Ember.Route.extend({
  model: function(params) {
    return $.getJSON('/books/' + params.id);
  },
  setupController: function(controller, model){
    this._super(controller,model);
    controller.set('model2', {bird:'is the word'});
  }
});

Example: http://emberjs.jsbin.com/cibujahuju/1/edit

If you need it to block the transition (like the model hook does) return a promise from the afterModel hook. You will need to manually keep track of the results from that hook and hook them up to your controller.

App.IndexRoute = Ember.Route.extend({
  model: function(params) {
    return $.getJSON('/books/' + params.id);
  },
  afterModel: function(){
    var self = this;
    return $.getJSON('/authors').then(function(result){
      self.set('authors', result);
    });
  }, 
  setupController: function(controller, model){
    this._super(controller,model);
    controller.set('authors', this.get('authors'));
  }
});

Example: http://emberjs.jsbin.com/diqotehomu/1/edit

If you answered no

Go ahead, let's return multiple models from the route's model hook:

App.IndexRoute = Ember.Route.extend({
  model: function() {
    return {
           model1: ['red', 'yellow', 'blue'],
           model2: ['green', 'purple', 'white']
    };
  }
});

Example: http://emberjs.jsbin.com/tuvozuwa/1/edit

If it's something that needs to be waited on (such as a call to the server, some sort of promise)

App.IndexRoute = Ember.Route.extend({
  model: function() {
    return Ember.RSVP.hash({
           model1: promise1,
           model2: promise2
    });
  }
});

Example: http://emberjs.jsbin.com/xucepamezu/1/edit

In the case of Ember Data

App.IndexRoute = Ember.Route.extend({
  var store = this.store;
  model: function() {
    return Ember.RSVP.hash({
           cats: store.find('cat'),
           dogs: store.find('dog')
    });
  }
});

Example: http://emberjs.jsbin.com/pekohijaku/1/edit

If one is a promise, and the other isn't, it's all good, RSVP will gladly just use that value

App.IndexRoute = Ember.Route.extend({
  var store = this.store;
  model: function() {
    return Ember.RSVP.hash({
           cats: store.find('cat'),
           dogs: ['pluto', 'mickey']
    });
  }
});

Example: http://emberjs.jsbin.com/coxexubuwi/1/edit

Mix and match and have fun!

App.IndexRoute = Ember.Route.extend({
  var store = this.store;
  model: function() {
    return Ember.RSVP.hash({
           cats: store.find('cat'),
           dogs: Ember.RSVP.Promise.cast(['pluto', 'mickey']),
           weather: $.getJSON('weather')
    });
  }, 
  setupController: function(controller, model){
    this._super(controller, model);
    controller.set('favoritePuppy', model.dogs[0]);
  }
});

Example: http://emberjs.jsbin.com/joraruxuca/1/edit

Answer 2

NOTE: for Ember 3.16+ apps, here is the same code, but with updated syntax / patterns: https://stackoverflow.com/a/62500918/356849

The below is for Ember < 3.16, even though the code would work as 3.16+ as fully backwards compatible, but it's not always fun to write older code.

---

You can use the Ember.RSVP.hash to load several models:

app/routes/index.js

import Ember from 'ember';

export default Ember.Route.extend({
  model() {
    return Ember.RSVP.hash({
      people: this.store.findAll('person'),
      companies: this.store.findAll('company')
    });
  },

  setupController(controller, model) {
    this._super(...arguments);
    Ember.set(controller, 'people', model.people);
    Ember.set(controller, 'companies', model.companies);
  }
});

And in your template you can refer to people and companies to get the loaded data:

app/templates/index.js

<h2>People:</h2>
<ul>
  {{#each people as |person|}}
    <li>{{person.name}}</li>
  {{/each}}
</ul>
<h2>Companies:</h2>
<ul>
  {{#each companies as |company|}}
    <li>{{company.name}}</li>
  {{/each}}
</ul>

This is a Twiddle with this sample: https://ember-twiddle.com/c88ce3440ab6201b8d58

Answer 3

I use something like the answer that Marcio provided but it looks something like this:

    var products = Ember.$.ajax({
        url: api + 'companies/' +  id +'/products',
        dataType: 'jsonp',
        type: 'POST'
    }).then(function(data) {
        return data;
    });

    var clients = Ember.$.ajax({
        url: api + 'clients',
        dataType: 'jsonp',
        type: 'POST'
    }).then(function(data) {
        return data;
    });

    var updates = Ember.$.ajax({
        url: api + 'companies/' +  id + '/updates',
        dataType: 'jsonp',
        type: 'POST'
    }).then(function(data) {
        return data;
    });

    var promises = {
        products: products,
        clients: clients,
        updates: updates
    };

    return Ember.RSVP.hash(promises).then(function(data) {
      return data;
    });  

Answer 4

Taking the accepted answer, and updating it for Ember 3.16+

app/routes/index.js

import Route from '@ember/routing/route';
import { inject as service } from '@ember/service';

export default class IndexRoute extends Route {
  @service store;

  async model() {
    let [people, companies] = await Promise.all([
      this.store.findAll('person'),
      this.store.findAll('company'),
    ]);


    return { people, companies };
  }

}

Note, it's recommended to not use setupController to setup aliases, as it obfuscates where data is coming from and how it flows from route to template.

So in your template, you can do:

<h2>People:</h2>

<ul>
  {{#each @model.people as |person|}}
    <li>{{person.name}}</li>
  {{/each}}
</ul>

<h2>Companies:</h2>

<ul>
  {{#each @model.companies as |company|}}
    <li>{{company.name}}</li>
  {{/each}}
</ul>

Answer 5

If you use Ember Data, it gets even simpler for unrelated models:

import Ember from 'ember';
import DS from 'ember-data';

export default Ember.Route.extend({
  setupController: function(controller, model) {
    this._super(controller,model);
    var model2 = DS.PromiseArray.create({
      promise: this.store.find('model2')
    });
    model2.then(function() {
      controller.set('model2', model2)
    });
  }
});

If you only want to retrieve an object's property for model2 , use DS.PromiseObject instead of DS.PromiseArray :

import Ember from 'ember';
import DS from 'ember-data';

export default Ember.Route.extend({
  setupController: function(controller, model) {
    this._super(controller,model);
    var model2 = DS.PromiseObject.create({
      promise: this.store.find('model2')
    });
    model2.then(function() {
      controller.set('model2', model2.get('value'))
    });
  }
});

Answer 6

The latest version of JSON-API as implemented in Ember Data v1.13 supports bundling of different resources in the same request very well, if you don't mind modifying your API endpoints.

In my case, I have a session endpoint. The session relates to a user record, and the user record relates to various models that I always want loaded at all times. It's pretty nice for it all to come in with the one request.

One caveat per the spec is that all of the entities you return should be linked somehow to the primary entity being received. I believe that ember-data will only traverse the explicit relationships when normalizing the JSON.

For other cases, I'm now electing to defer loading of additional models until the page is already loaded, ie for separate panels of data or whatever, so at least the page is rendered as quickly as possible. Doing this there's some loss/change with the "automatic" error loading state to be considered.