ruby-on-rails - rails渲染但ajax失败

Question

这是我的ajax

$.ajax({
    type: "GET",
    url: '/posts/product_list.json',
    data: {sub_cat_id: sub_category_id},
        dataType: 'json',
        success: function(data) {
                console.log('success');
        },
        error: function(data){
            console.log('failed');
        }
    });

这是我的控制器动作

respond_to :json,only: :product_list
def product_list
    @products = Product.find_by_sub_category_id params[:sub_cat_id]
    respond_with @products
  end

我的 product_list.json.erb 文件有

test response

在检查网络链接显示test但我的控制台显示failed

这是我的控制台输出

Started GET "/posts/product_list.json?sub_cat_id=41" for 127.0.0.1 at 2013-10-02 21:21:47 +0530
Processing by PostsController#product_list as JSON
  Parameters: {"sub_cat_id"=>"41"}
  Product Load (0.8ms)  SELECT "products".* FROM "products" WHERE "products"."sub_category_id" = 41 LIMIT 1
  Rendered posts/product_list.json.erb (0.1ms)
Completed 200 OK in 81ms (Views: 14.5ms | ActiveRecord: 4.1ms | Solr: 0.0ms)

工作控制器

这是有效的

respond_to do |format|
      format.json { render json: { products: @products}}
    end

但无法渲染product_list.json.erb

你有什么主意吗。