python - 你如何告诉 pylint protobuf 生成的对象的成员是什么？

Question

我想为一组 protobuf 消息发布一个 python 包。 protobuf 编译器 (protoc) 生成一个 python 库，它实际上并不定义典型意义上的类型/类，而是动态构造它们。有什么方法可以提示 pylint 这些类的成员和字段是什么？

例如，考虑以下简单的 protobuf 消息规范:

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

编译器生成了如下一长串代码:

# Generated by the protocol buffer compiler.  DO NOT EDIT!
# source: test.proto

import sys
_b=sys.version_info[0]<3 and (lambda x:x) or (lambda x:x.encode('latin1'))
from google.protobuf import descriptor as _descriptor
from google.protobuf import message as _message
from google.protobuf import reflection as _reflection
from google.protobuf import symbol_database as _symbol_database
from google.protobuf import descriptor_pb2
# @@protoc_insertion_point(imports)

_sym_db = _symbol_database.Default()




DESCRIPTOR = _descriptor.FileDescriptor(
  name='test.proto',
  package='',
  serialized_pb=_b('\n\ntest.proto\"1\n\x06Person\x12\x0c\n\x04name\x18\x01 \x02(\t\x12\n\n\x02id\x18\x02 \x02(\x05\x12\r\n\x05\x65mail\x18\x03 \x01(\t')
)
_sym_db.RegisterFileDescriptor(DESCRIPTOR)




_PERSON = _descriptor.Descriptor(
  name='Person',
  full_name='Person',
  filename=None,
  file=DESCRIPTOR,
  containing_type=None,
  fields=[
    _descriptor.FieldDescriptor(
      name='name', full_name='Person.name', index=0,
      number=1, type=9, cpp_type=9, label=2,
      has_default_value=False, default_value=_b("").decode('utf-8'),
      message_type=None, enum_type=None, containing_type=None,
      is_extension=False, extension_scope=None,
      options=None),
    _descriptor.FieldDescriptor(
      name='id', full_name='Person.id', index=1,
      number=2, type=5, cpp_type=1, label=2,
      has_default_value=False, default_value=0,
      message_type=None, enum_type=None, containing_type=None,
      is_extension=False, extension_scope=None,
      options=None),
    _descriptor.FieldDescriptor(
      name='email', full_name='Person.email', index=2,
      number=3, type=9, cpp_type=9, label=1,
      has_default_value=False, default_value=_b("").decode('utf-8'),
      message_type=None, enum_type=None, containing_type=None,
      is_extension=False, extension_scope=None,
      options=None),
  ],
  extensions=[
  ],
  nested_types=[],
  enum_types=[
  ],
  options=None,
  is_extendable=False,
  extension_ranges=[],
  oneofs=[
  ],
  serialized_start=14,
  serialized_end=63,
)

DESCRIPTOR.message_types_by_name['Person'] = _PERSON

Person = _reflection.GeneratedProtocolMessageType('Person', (_message.Message,), dict(
  DESCRIPTOR = _PERSON,
  __module__ = 'test_pb2'
  # @@protoc_insertion_point(class_scope:Person)
  ))
_sym_db.RegisterMessage(Person)


# @@protoc_insertion_point(module_scope)

Answer 1

似乎不支持自动向 Pylint 提示 protobuf 消息中字段的名称，因此我拼凑了一个 Pylint 的小扩展来静态确定这些。

介绍 pylint-protobuf :

from example_pb2 import Person
p = Person()
p.invalid_field = 123

用法:

$ pip install pylint-protobuf
$ pylint --load-plugins=pylint_protobuf example.py
************* Module example
E:  3, 0: Field 'invalid_field' does not appear in the declared
fields of protobuf-generated class 'Person' and will raise
AttributeError on access (protobuf-undefined-attribute)

---

公平警告:它还处于 alpha 阶段，不支持的功能(目前!)包括嵌套导入和重复字段。