Trouble consuming json rest data in ember-data - ember.js

Question

I'm trying to parse a json dataset in my ember data models but this throws an error in het console:
Uncaught TypeError: Cannot call method '_create' of undefined
DS.Store.Ember.Object.extend.materializeRecord
DS.Store.Ember.Object.extend.findByClientId
What am I doing wrong here?
This is the data I receive from the server:
{
"newsitems": [
{
"date": "2013-02-10T15:00:00+01:00",
"id": "1",
"images": [
{
"id": "1",
"value": "image.JPG"
},
{
"id": "3",
"value": "anotherimage.jpg"
}
],
"slug": "some-slug",
"summary": "some summary",
"text": "some text",
"thumb": {
"id": "2",
"value": "someimage.JPG"
},
"title": "Some title",
"type": "1",
"videos": [
{
"id": "AEOpX8tmiUI",
"value": "AEOpX8tmiUI"
},
{
"id": "kxopViU98Xo",
"value": "kxopViU98Xo"
}
]
}
]
}
These are my models:
App.NewsitemThumb = DS.Model.extend({
value: DS.attr('string'),
newsitem: DS.belongsTo('App.Newsitem')
});
App.NewsitemImage = DS.Model.extend({
value: DS.attr('string'),
newsitem: DS.belongsTo('App.Newsitem')
});
App.NewsitemVideo = DS.Model.extend({
value: DS.attr('string'),
newsitem: DS.belongsTo('App.Newsitem')
});
App.Newsitem = DS.Model.extend({
slug: DS.attr('string'),
type: DS.attr('string'),
title: DS.attr('string'),
summary: DS.attr('string'),
text: DS.attr('string'),
date: DS.attr('date'),
thumb: DS.belongsTo('App.NewsitemThumb'),
images: DS.hasMany('App.NewsitemImage'),
videos: DS.hasMany('App.NewsitemVideo')
});
For the record, any suggestions for optimizing these models are welcome. It feels so weird to make 3 models for video, images and a thumb.

Answer 1

According to this issue, this error pops up when you don't specify an explicit mapping for a hasMany relationship in your adapter.
Try defining your store as
App.Store = DS.Store.extend({
revision: 11,
adapter: DS.RESTAdapter.extend({
serializer: DS.RESTSerializer.extend({
init: function() {
this._super();
this.map("App.Newsitem", {
images: { embedded: "load" },
videos: { embedded: "load" }
});
}
})
})
});