从嵌套模型渲染 JSON 时没有将符号隐式转换为整数

Question

我是 rails API 的新手。对于以下语法，我在 rails 服务器控制台中得到 "TypeError No implicit conversion of Symbol into Integer"。

def show
@product = Product.find(params[:id])
render json: @product.to_json(:include => 
  { :items => 
    { :only => 
      [:id, 
        :description, 
        :item_name, 
        :item_code, 
        :display_tag, 
        :price,
       {:include => 
        :item_images [:id, 
        :image_url]
      }
      ]
    }
  }
)
end

它应该在请求 URL 时显示 item_images 的数组以及项目（例如 http://localhost:4000/products/1）我的 JSON 是这样的：

{
"id": 1,
"product_name": "Foundation",
"description": "test",
"image_file_name": "text.jpg",
"image_content_type": "image/jpeg",
"image_file_size": 341279,
"image_updated_at": "2018-10-24T09:28:49.000Z",
"image_url": "http://localhost:3000/system/products/1/original/text.jpg",
"created_at": "2018-08-28T14:50:29.000Z",
"updated_at": "2018-10-24T09:28:50.000Z",
"items": [
    {
        "id": 6,
        "item_name": "LOTUS WHITE GLOW COMPAC POWDER",
        "item_code": "SF264",
        "display_tag": "New",
        "description": "SKIN WHITENING AND BRIGHTENING NOURISHING\r\nSUITABLE FOR ALL SKIN TYPES\r\nULTRA-FINE SILTY FORMULA\r\nSILKY SMOOTH AND DELICATE TEXTURE\r\nCONTAINS NATURAL PLANT INGREDIENTS CAN BLOCK THE INSIDE DARK",
        "price": "1250.0"
    },
    {
        "id": 7,
        "item_name": "Test",
        "item_code": "100",
        "display_tag": "New",
        "description": "lorem ipsum",
        "price": "200.0"
    }
]}

有什么帮助吗？

Answer 1

看：

{:include => :item_images [:id, :image_url]}

:item_images [:id, 不对。你的意思可能是这样的：

{:include => :item_images => {:only => [:id, :image_url]}}

另外，我认为 include 也在错误的位置。 :include 应该是另一个键，例如 :only 在该哈希中（现在 :include 在 :only 数组中）。所以这应该有效：

def show
  @product = Product.find(params[:id])
  render json: @product.to_json(:include => 
    { :items => 
      { :only => 
        [:id, 
          :description, 
          :item_name, 
          :item_code, 
          :display_tag, 
          :price
        ],
        :include => 
        {
          :item_images => {:only => [:id, :image_url]}
        }
      }
    }
  )
end

从嵌套模型渲染 JSON 时没有将符号隐式转换为整数

No implicit conversion of symbol into integer while rendering JSON from nested model

ruby-on-rails

rails-api

ruby-on-rails-4

ruby-on-rails-5