Ember.js belongsTo relationship undefined but hasMany array populated

Question

Using ember-data with Django REST adapter. Having trouble setting content of controllers based on the model received's relationships in setupController hooks

I put break points in and they went in this order:

ArtistRoute.model
ArtistTrackRoute.model
ArtistRoute.setupController
ArtistTrackRoute.setupController

Please see comments in those functions for more info / questions.

A track's primary artist is track -> belongsTo -> album -> belongsTo -> artist

Artists: artist -> hasMany -> albums

Album album -> belongsTo -> artist album -> hasMany -> tracks

Track track -> belongsTo -> album

I've checked my api output, and the resource link is definitely there.

Here's my models:

App.Album = DS.Model.extend({
    'title' : DS.attr('string'),
    'slug' : DS.attr('string'),
    'year' : DS.attr('number'),
    'type' : DS.attr('string'),
    'image' : DS.attr('string'),
    'genre' : DS.attr('string'),
    'tracks' : DS.hasMany('App.Track'),
    'artist' : DS.belongsTo('App.Artist')
});

App.Track = DS.Model.extend({
    'title' : DS.attr('string'),
    'slug' : DS.attr('string'),
    'artists_titles' : DS.attr('string'),
    'artists_ids' : DS.attr('string'),
    'artists_slugs' : DS.attr('string'),
    'year' : DS.attr('number'),
    'genre' : DS.attr('string'),
    'label' : DS.belongsTo('App.Label'),
    'album' : DS.belongsTo('App.Album'),
    'creator' : DS.attr('number'),
    'created' : DS.attr('date'),
    'modified' : DS.attr('date'),
});

App.Artist = DS.Model.extend({
    'title' : DS.attr('string'),
    'image' : DS.attr('string'),
    'slug' : DS.attr('string'),
    'genre' : DS.attr('string'),
    'creator' : DS.attr('number'),
    'created' : DS.attr('date'),
    'modified' : DS.attr('date'),
    'absoluteUrl' : DS.attr('string'),
    'resourceUri' : DS.attr('string'),
    'albums' : DS.hasMany('App.Album'),
    'getImageURL' : function() {
        return (this.get('image')) ? '/static/img/' + this.get('image') + '.jpg' : false;
    }.property('image')
});

Here's my Routes:

App.ArtistRoute = Ember.Route.extend({
    'model' : function(params) {
        // here first
        return App.Artist.find(params.artist_id);
    },
    'serialize' : function(model) {
        "use strict";
        return {
            'artist_id' : model.get('id'),
            'artist_slug' : model.get('slug')
        };
    },
    'setupController' : function(controller, artist) {
        // here third...
        // I inspected artist._data
        // artist._data.hasMany.albums = [1]
        this.controllerFor('artist').set('content', artist);
    }
});

App.ArtistTrackRoute = Ember.Route.extend({
   'model' : function(params) {
        // here second
       return App.Track.find(params.track_id);
   },
   'serialize' : function(model) {
       "use strict";
       return {
           'track_id' : model.get('id'),
           'track_slug' : model.get('slug')
       }
   },
   'setupController' : function(controller, track) {
        // here fourth... I inspected the track data object
        // track._data.belongsTo.album == undefined

        // what I'm trying to achieve here is to set the album
        // controller based on the belongsTo relationship
        // this.controllerFor('album').set('content', track.get('album'))
       this.controllerFor('track').set('content', track);

   }
});

Moreover, when breakpointing in ArtistAlbumRoute.setupController, I noticed that album._data.hasMany.tracks == [1] But album._data.belongsTo.artist == undefined.... wtf?!?!?!

I'm still having a hard time wrapping my head around Ember so any extra advice is much appreciated. Thanks!

Additionally, after the page has loaded and I open console, what would I type in to access the controllers to see what is set?

ilovett ilovett · Accepted Answer · 2013-03-25T07:24:12

It turned out to have everything to do with my Tastypie Resource setup...

https://github.com/escalant3/ember-data-tastypie-adapter/issues/18

My TrackResource looked like this:

class TrackResource(ModelResource):

    album = fields.ToOneField('samped.api.resources.AlbumResource', 'album')

    class Meta:
        queryset = Track.objects.all()

All I had to do was add "_id" to the album

class TrackResource(ModelResource):

    album_id = fields.ToOneField('samped.api.resources.AlbumResource', 'album')

    class Meta:
        queryset = Track.objects.all()

Then I was able to do:

App.ArtistTrackRoute = Ember.Route.extend({
   'model' : function(params) {
       return App.Track.find(params.track_id);
   },
   'serialize' : function(model) {
       "use strict";
       return {
           'track_id' : model.get('id'),
           'track_slug' : model.get('slug')
       }
   },
   'setupController' : function(controller, track) {
       this.controllerFor('track').set('content', track);
       this.controllerFor('album').set('content', track.get('album'))
   }
});

Ember.js belongsTo relationship undefined but hasMany array populated

1 Answers