Filtering on hasMany by id without fetching object

I have a model with a hasMany collection, and I would like to determine whether or not an object exists in that collection, given the ID of an object.

var searchFor = "someid";
var filtered = parent.get('children').filter(function (item) { return item.get('') == searchFor; });
var exists = filter.get('length') > 0;

However, this makes a remote request to the child endpoint with each iteration of the filter, which is unnecessary since it knows the IDs already. Is there any way to work around this?


Looks like the explicit comparison against is unnecessary:

var exists = parent.get('children').findBy('child', child);

And that does it.

While that fixes my case, it is still strange that Ember Data forces the resolution of the entire object even if it’s only being used in a filter, and not being asked for as an instance. I would understand resolving the full object if I were requesting an instance of child, but not when I’m only interested in using the child object’s ID in a filter, a property that already exists in the cache.

Actually, this didn’t do it. Ember Data still fetches the entire object…