application.js

/* app/routes/application.js */
cancel(model, transitionToRoute) {
      // relationshipsIsDirty is custom.  hasDirtyAttributes comes with Ember Data
      if (model.get('hasDirtyAttributes') || model.get('relationshipsIsDirty')) {
        Ember.$('#crud').openModal();
        // other stuff....attach the model and transitionToRoute to a transition service to be used when user clicks yes/no in modal
      } else {
        if (model.get('isNew')) {
          model.deleteRecord();
        }
        this.transitionTo(transitionToRoute);
      }
},