ember.js - Navigating to Record works, but deep link throws error? -

i have simple emberjs application 2 simple models (ember-model). accounts , items, while account hasmany items.

so when navigate #/accounts/1/items links in application works fine. when directly reload #/accounts/1/items error:

assertion failed: value #each loops on must array. passed <app.account:ember335> (wrapped in (generated items controller)) ember.js?body=1:382 uncaught typeerror: object [object object] has no method 'addarrayobserver' ember.js?body=1:19476 assertion failed: emptying view in inbuffer state not allowed , should not happen under normal circumstances. there bug in application. may due excessive property change notifications. ember.js?body=1:382 

this how app looks like:

app.router.map ()->   @resource 'accounts', ->     @resource 'account', path: ':account_id', ->       @resource 'items'  app.accountroute = ember.route.extend   model: (params) ->     app.account.find(params.account_id)  app.itemsroute = ember.route.extend   model: ->     @.modelfor('account').get('items')  app.account = ember.model.extend   name: ember.attr('string')   item_ids: ember.attr(),   items: (->     app.items.find(@.get('comment_ids'))   ).property('comment_ids')  app.item = ember.model.extend   name: ember.attr('string') 

controllers standard (empty).

in js console call works fine , returns correct results, after error thrown (and nothing rendered):

 app.account.find(1).get('items') 

i have no idea why happening , code seems straight forward annoying not have clue. has idea?

i no ember-data expert, seems returning promise. therefore should try:

app.itemsroute = ember.route.extend({   model : function(){     var accountpromise = app.account.find(1);     var itemspromise = ember.deferred.create();     accountpromise.then(function(account){       itemspromise.resolve(account.get("items"));     });     return itemspromise;   } }); 

why have way?

1. app.account.find(1); performs asynchronous call , therefore returns promise.
2. that's why can't return items, have wait accountpromise fulfilled.
3. you return new promise (itemspromise) gets fulfilled when accountpromise gets fulfilled.
4. because return promise, ember waits fulfilled , uses result model controller.

ps: seems little bit complicated me. thinks work, there might more elegant solution.