ember-data with filter

ember-data-chat.js

App = Ember.Application.create();

App.store = DS.Store.create({
  adapter: DS.RESTAdapter.create()
})

App.set("room_id", 1);

App.Models = Ember.Namespace.create();
App.Mixins = Ember.Namespace.create();

App.Mixins.ChatMessage = Ember.Mixin.extend({
  // common functionality here?
})

App.ChatMessage = Ember.Object.extend(App.Mixins.ChatMessage);

App.Models.ChatMessage = DS.Model.extend(App.Mixins.ChatMessage, {
  contents: DS.attr("string"),
  room_id:  DS.attr("string")
})

App.chatMessages = Ember.ArrayController.create({

  init: function() {
    App.get("eventQueue").on("message-posted", _(this.messagePosted).bind(this));
  },

  roomChanged: function() {
    this.set("content", []);
  }.bind("App.room_id"),

  messages: function() {
    return App.get("serverChatMessages").concat(this.get("content"));
  }.property("App.serverChatMessages", "content").cacheable(),

  messagePosted: function(data) {
    this.pushObject(App.ChatMessage.create(data));
  },

  postMessage: function(contents) {
    var room_id = App.get("room_id");

    var message = App.store.createRecord(App.Models.ChatMessage, {
      contents: contents,
      room_id: room_id
    });

    this.pushObject(message);
    App.store.commit();
  }
})

App.serverChatMessages = Ember.ArrayController.create({
  init: function() {
    this.loadData()
  },

  roomChanged: function() {
    this.loadData()
  }.observes("App.room_id"),

  loadData: function() {
    var room_id = App.get("room_id");
    this.set("content", App.store.find(App.Models.ChatMessage, {room_id: room_id}))
  }
});