Serialization of records without id in the built-in mixin record

Question

I started looking for a built-in recording mixin to serialize / deserialize records with hasMany / belongs to relationships.

Model:

 App.Post= DS.Model.extend({

   comment: DS.belongsTo('comment'),
   name:     DS.attr('string')
 });

 App.Comment =DS.Model.extend({

  post: DS.belongsTo('Post'),
  value:   DS.attr('string')
 });

Serializer:

App.PostSerializer = DS.RESTSerializer.extend(DS.EmbeddedRecordsMixin, {
   attrs: {
      comments: {embedded: 'always'}
   }
});

When I try to save the model, I got the following error.

   var model = this.store.createRecord('post');

    model.get('comments').pushObject(this.store.createRecord('comment'));


    model.setProperties({
        name: 'test'
    });

    model.save();

Error: approval failed: you must specify the identifier for App.Comment in the object passed for push. Only an error in the browser console, but on the backend, the data goes as expected.

So, I started looking for a workaround and found something interesting in https://gist.github.com/vampolo/8f8237cce2b8a52ab9d4 .

source: http://vincenzo-ampolo.net/2014/09/21/ember-data-embedded-records-without-ids-ready-to-go/

Following this link, I changed my serializer as follows.

Serializer (changed):

  App.PostSerializer=DS.RESTSerializer.extend(DS.EmbeddedRecordsMixin,DS.NoKeyMixin, {
        attrs: {
          comments: {embedded: 'always',noKey: true}
        }
     });

, .

Uncaught TypeError: embeddedRecord.serialize .

. .