Aiogram 3调用set_my_commands启动报错求助

错误信息 #

raise validation_error
pydantic.error_wrappers.ValidationError: 1 validation error for BotCommand
description
  field required (type=value_error.missing)
Exception ignored in: <function _ProactorBasePipeTransport.__del__ at 0x0424A148>
Traceback (most recent call last):
  File "D:\Programs\Python\Python38-32\lib\asyncio\proactor_events.py", line 116, in __del__
  File "D:\Programs\Python\Python38-32\lib\asyncio\proactor_events.py", line 108, in close
  File "D:\Programs\Python\Python38-32\lib\asyncio\base_events.py", line 711, in call_soon
  File "D:\Programs\Python\Python38-32\lib\asyncio\base_events.py", line 504, in _check_closed
RuntimeError: Event loop is closed

核心代码片段 #

project.core.utils.commands/commands.py #

from aiogram import Bot
from aiogram.types import BotCommand, BotCommandScopeDefault

async def set_commands(bot: Bot):
    commands = [BotCommand(command='start', descriptions='Begin work')]
    await bot.set_my_commands(commands, BotCommandScopeDefault())

core.handlers.basic.py #

from aiogram.types import Message

async def get_start(message: Message):
    await message.answer(f'Hi {message.from_user.first_name}. Welcome!')

project.main.py #

from aiogram import Bot, Dispatcher
from core.handlers.basic import get_start
import asyncio
from core.settings import settings
from aiogram.filters import Command
from core.utils.commands import set_commands

async def start_bot(bot: Bot):
    print('Bot started!')
    await set_commands(bot)

async def stop_bot(bot: Bot):
    print('Bot stopped!')

async def start():
    bot = Bot(token=settings.bots.bot_token, parse_mode='HTML')
    dp = Dispatcher()
    dp.startup.register(start_bot)
    dp.shutdown.register(stop_bot)
    dp.message.register(get_start, Command(commands=['start']))

    try:
        await dp.start_polling(bot)
    finally:
        await bot.session.close()

if __name__ == "__main__":
    asyncio.run(start())

关键信息 #

• 仅调用await set_commands(bot)时触发错误，移除后机器人正常运行
• RuntimeError: Event loop is closed片段重复出现10次
• 代码基于视频教程，但使用了更新版本的依赖库
• 依赖版本：Python 3.8、aiogram 3.0.0.b7、asyncio 3.4.3、aiohttp 3.8.4、Windows 10

已尝试的解决方法 #

• 搜索到的方案多与aiohttp/FastApi相关，不适用
• 在finally块后添加await asyncio.sleep(0.1)
• 替换asyncio.run(start())的写法
• 尝试多种非官方建议
• 拒绝通过BotFather添加命令（无法设置BotCommandScope）
• 对比教程代码，仅依赖版本有差异

解决方案 #

错误原因 #

Aiogram 3中BotCommand类的参数名是**description（单数）**，你代码里写的是descriptions（复数），导致Pydantic验证时找不到必填的description字段，直接抛出ValidationError，进而导致程序提前退出，后续出现事件循环已关闭的RuntimeError。教程代码无报错是因为旧版本Aiogram使用的是descriptions参数，新版本做了字段名修改。

修复代码 #

修改commands.py中的BotCommand初始化代码，把descriptions改成description：

from aiogram import Bot
from aiogram.types import BotCommand, BotCommandScopeDefault

async def set_commands(bot: Bot):
    # 把descriptions改为description
    commands = [BotCommand(command='start', description='Begin work')]
    await bot.set_my_commands(commands, BotCommandScopeDefault())

修改后重新启动机器人，ValidationError会消失，后续的RuntimeError也会因为程序正常执行而不再出现。

内容的提问来源于stack exchange，提问作者RobinGoood