album_tracks_route.coffee

Testcase.AlbumTracksRoute = Ember.Route.extend
  model: ->
    @modelFor('album').get('tracks')

models.coffee

Testcase.Track = DS.Model.extend
  title: DS.attr 'string'
  genre: DS.attr 'string'
  releaseDate: DS.attr 'string'
  file: DS.attr 'string'
  cover: DS.attr 'string'
  album: DS.belongsTo 'album'

Testcase.Album = DS.Model.extend
  title: DS.attr 'string'
  releaseDate: DS.attr 'date'
  cover: DS.attr 'string'
  tracks: DS.hasMany 'track'

router.coffee

Testcase.Router.map ()->
  @resource 'albums', ->
    @route('new')
    @route('edit')
    @resource 'album', {path: ':album_id'}, ->
      @resource 'tracks'