title: Ember Data: Uncaught TypeError: Cannot read property 'push' of undefined
body: <p>I'm new to <strong>Ember CLI</strong> and I've been trying to push data to hasMany relationship after it has been created, but I'm getting this weird error <code>Uncaught TypeError: Cannot read property 'push' of undefined</code> Everything seems to be fine <code>this.store.createRecord()</code> is working but <code>.findRecord .push .peekRecor</code>d is not working.</p>
  
  <p><strong>My controller</strong>:</p>
  
  <pre><code>var VideoToAdd = this.store.find('video', this.get('ActiveCanvas'));
  console.log(this.get('ActiveCanvas'));
  VideoToAdd.get('hotspots').push(newHotspot);
  </code></pre>
  
  <p><strong>Video Model</strong></p>
  
  <pre><code>import DS from 'ember-data';
  
  export default DS.Model.extend({
    title: DS.attr(),
    file: DS.attr(),
    hotspots: DS.hasMany('hotspot')
  });
  </code></pre>
  
  <p><strong>Hotspot Model:</strong></p>
  
  <pre><code>import DS from 'ember-data';
  
  export default DS.Model.extend({
    title: DS.attr(),
    onVideo: DS.belongsTo('video'),
    toVideo: DS.attr()
  });
  </code></pre>
  
  <p>Please tell me what's going wrong.</p>