首页 > 解决方案 > 在 python 3 中无法访问(嵌套)枚举类型(proto3)

问题描述

我无法访问琐碎的协议缓冲区消息中的(嵌套)枚举。我尝试了任何一种方式,嵌套或分离DataNodeManagement!:

syntax = "proto3";

message DataNodeManagement {
  string name = 1;
  string id = 2;
  string origin = 3;
  ConnectionType con_type = 4;
  enum ConnectionType {
    UNKNOWN = 0;
    MQTT = 1;
  }
}

我正在使用此代码在我的消息中填充数据:

config = data_node_pb2.DataNodeManagement()
config.name = "Scanner1"
config.id = key
config.origin = "PC1"
config.con_type = data_node_pb2.ConnectionType.MQTT
# or 
# config.con_type = data_node_pb2.DataNodeManagement.ConnectionType.MQTT

datasource.advertise_data_node(config.SerializeToString())

它抱怨:

Traceback (most recent call last):
  File "scanner-connector.py", line 144, in <module>
    config.con_type = data_node_pb2.ConnectionType.MQTT
AttributeError: 'EnumTypeWrapper' object has no attribute 'MQTT'

各自:

Traceback (most recent call last):
  File "scanner-connector.py", line 144, in <module>
    config.con_type = data_node_pb2.DataNodeManagement.ConnectionType.MQTT
AttributeError: type object 'DataNodeManagement' has no attribute 'ConnectionType'

我正在使用这些版本:

python --version
Python 3.6.6 :: Anaconda custom (64-bit)

protoc --version
libprotoc 3.6.1

作为初学者,我有什么特别之处吗?

标签: pythonpython-3.xprotocol-buffers

解决方案


您必须跳过枚举名称才能访问枚举中的值。从protocol-buffers python-tutorial中可以看出,枚举是在消息中定义的

message Person {
  required string name = 1;
  required int32 id = 2;
  optional string email = 3;

  enum PhoneType {
    MOBILE = 0;
    HOME = 1;
    WORK = 2;
  }

  message PhoneNumber {
    required string number = 1;
    optional PhoneType type = 2 [default = HOME];
  }

  repeated PhoneNumber phones = 4;
}

阅读消息部分中,枚举是通过以下方式访问的

import addressbook_pb2
addressbook_pb2.Person.MOBILE

所以在你的例子中应该是data_node_pb2.DataNodeManagement.MQTT


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