传递整数在Alamofire POST请求中失败（Json Serilization error）

Question

 let parameters : [ String : Any] = [
            "test_id": 1,
            "std_id": 1,
            "d_mins": 10
        ]

       Alamofire.request("http://cloud.com/xxx",method: .post,parameters: parameters,encoding: JSONEncoding.default,headers: headers).responseJSON { response in
            print(response)
            print(response.result)
           print(response.result.isSuccess)
        }

    }

面对以下错误

通知 FAILURE：responseSerializationFailed（Alamofire.AFError.ResponseSerializationFailureReason.jsonSerializationFailed（Error Domain = NSCocoaErrorDomain Code = 3840＆＃34; No value。＆＃34; UserInfo = {NSDebugDescription = No value。}）） 失败 假