Question

我如何强制我的Grape Entity总是返回一个数组（集合），即使它只是一个单一的对象？我听说有些人创建了一个在他们的端点内调用的辅助方法，但我没有找到任何人在网上做这个的例子。

实体的默认功能是，如果只返回单个文档（mongoid对象），则返回一个对象。如果返回一个文档集合然后它返回一个数组，我不希望我的客户端应用程序每次都要检查是否从我的API返回了一个对象或一个数组。

## Resource (HTTP Endpoint)
desc 'List departments a user can and cannot access'
params do
  requires :user_id
end
get :department_access do
  @user = BACKBONE::User.find(@access_key.user_id)
  requires_admin!
  user = BACKBONE::User.find(params[:user_id])
  can_access = BACKBONE::Department.user_can_access(user)
  no_access = BACKBONE::Department.user_cannot_access(user)
  present_success can_access
  present :can_access, can_access, with: BACKBONE::Entities::DepartmentBase
  present :no_access, no_access, with: BACKBONE::Entities::DepartmentBase
end

-

## Entity
module BACKBONE
  module Entities
    class DepartmentBase < BACKBONE::Entities::Mongoid
      expose :name
      expose :prefix
      with_options(format_with: :mongo_id) do
        expose :company_id
      end
    end
  end
end

JSON响应

{
    "status": "success",
    "request_time": 0.009812,
    "records": 1,
    "can_access": {
        "id": "59699d1a78cee4f8d07528fc",
        "created_at": "2017-07-14T21:42:02.666-07:00",
        "updated_at": "2017-07-14T21:42:02.666-07:00",
        "name": "Tenant Improvement",
        "prefix": "CACC",
        "company_id": "596927fb670f6eec21c4f409"
    },
    "no_access": {
        "id": "59699cca78cee4f8d07528fb",
        "created_at": "2017-07-14T21:40:42.005-07:00",
        "updated_at": "2017-07-14T21:40:42.005-07:00",
        "name": "Field Operations",
        "prefix": "CACC",
        "company_id": "596927fb670f6eec21c4f409"
    }
}

Answer 1

同事和我想出了一个带帮助器的解决方案，创建一个总是返回一个数组的辅助方法：

def present_array(key, data, entity)
  d = (data.class.respond_to? :count) ? [data] : data
  d = [] if d.nil?
  present key, d, entity
end

强制Grape Entity总是返回一个数组？

1 个答案: