Ember observes async belongsTo relationship attribute on load

Question

I am trying observe an async belongsTo relationship attribute. I only want to observe changes that come from the api. So I am thinking of a one-way binding and observing that. I'm just not certain how to go about that.

This jsbin http://jsbin.com/yaxame/1 shows the binding as a normal two way binding. Each time 'someone' 'isHappy' it alerts you that 'Someone is happy'. But I would like it to only alert when the data comes in from the api, and not the user input.

two-way binding:

isHappyDidChange: function() {
  if (this.get('model.spouse.isHappy')) {
    alert('Someone is happy');
  }
}.observes('model.spouse.isHappy')

I realize this jsbin http://jsbin.com/yaxame/2 is wrong as you need to trigger the binding template. So what is the correct way?

one-way incorrect binding:

isHappyOneWay:  Ember.Binding.oneWay("model.spouse.isHappy"),

isHappyDidChange: function() {
  if (this.get('model.spouse.isHappy')) {
    alert('Someone is happy');
  }
}.observes('isHappyOneWay')

Updated thought:

If I could just observe isLoaded like this:

isHappyDidChange: function() {
  if (this.get('model.spouse.isHappy')) {
    alert('Someone is happy');
  }
}.observes('model.spouse.isLoaded')

Then that would be great, it might solve my problem. But the isLoaded doesn't actually mean the model is loaded... http://jsbin.com/yaxame/3

Thanks!

Answer 1

Observing isFulfilled does the trick:

isHappyDidChange: function() {
  if (this.get('spouse.isHappy')) {
    alert('Someone is happy');
  }
}.observes('spouse.isFulfilled')

as seen in the jsbin http://jsbin.com/yaxame/4/

Update

Still doesn't work for updating the record. http://jsbin.com/yaxame/5/ Tried observing 'didUpdate' as well but that didn't work. http://jsbin.com/yaxame/6/ But I'm okay with at it at least firing after fulfilling for now.