Question

@test = Test.find(params[:test_id].to_i)
group_tests_id = @test.group_tests.map(&:group_id)
@std = Student.joins(:group_students).where("group_id IN (?)",group_tests_id).uniq
render :json => {:students => @std.as_json(include: [:user.as_json(only: [:id, :first_name])]), :test => @test.as_json()}

每件事情都很好。

我收到了这个结果

{
    "students": [
        {
            "id": 38,
            "user_id": 34,
            "created_at": "2017-08-07T12:30:02.120+05:00",
            "updated_at": "2017-08-07T12:30:02.120+05:00",
            "user": {
                "id": 34,
                "username": "taimoor123",
                "created_at": "2017-08-07T12:30:02.067+05:00",
                "updated_at": "2017-08-07T12:33:19.273+05:00",
                "first_name": "Muhammad Taimoor",
                "second_name": "Sultani",
                "school_name": "Moon Public School",
                "section_name": "Blue 10th",
                "gender": "Male",
                "age": 23,
                "role": "Student",
                "school_id": 1,
                "section_id": 2,           
            }
        }
    ],
    "test": {
        "id": 33,
        "name": "Test 8/7/2017",
        "attempt_time": 15,
        "teacher_id": 1
    }
}

但我只想在id对象中first_name和user student。我很困惑，为什么嵌套包含在这里不起作用。我们将不胜感激。提前致谢。

Answer 1

问题出在这一行：

render :json => {:students => @std.as_json(include: [:user.as_json(only: [:id, :first_name])]), :test => @test.as_json()}

根据documentation，嵌套包含是通过以下方式执行的：

object.as_json(include: { nested_object: { only: [:nested_object_field] } })

因此，您需要将该行更正为：

render :json => {:students => @std.as_json(include: { user: { only: [:id, :first_name] } }), :test => @test.as_json()}

嵌套包括在渲染JSON期间不在Rails 4中工作

1 个答案: