Question: 如何在 run_preprocessor 中对 matcher 的 permission_updater 进行修改?

[Ailitonia]

问题描述

我希望能在 run_preprocessor 中对 matcher 的 permission_updater 进行动态的调整
首先编写了一个这样的 run_preprocessor:

from nonebot.matcher import Matcher
from nonebot.permission import Permission
from nonebot.adapters.onebot.v11.bot import Bot
from nonebot.message import run_preprocessor


class TestPermission:
    def __init__(self, self_id: str) -> None:
        self.self_id = self_id

    async def __call__(self, bot: Bot) -> bool:
        return bot.self_id == self.self_id


def test_permission_updater(self_id: str) -> Permission:
    return Permission(TestPermission(self_id=self_id))


@run_preprocessor
async def unique_bot_responding_limit(bot: Bot, matcher: Matcher):
    matcher.permission_updater(test_permission_updater(self_id=bot.self_id))

然后, 在运行一个类似这样的 matcher 时:

test = on_command('test')

@test.got('arg', prompt='please input arg')
async def handle_arg(arg: str = ArgStr('arg')):
    ...

会抛出如下异常:

Traceback (most recent call last):
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\internal\matcher.py", line 668, in run
    await self.simple_run(bot, event, state, stack, dependency_cache)
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\internal\matcher.py", line 635, in simple_run
    await handler(
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\dependencies\__init__.py", line 89, in __call__
    values = await self.solve(**kwargs)
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\dependencies\__init__.py", line 191, in solve
    await param._solve(**params)
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\internal\params.py", line 151, in _solve
    solved = await task
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\internal\matcher.py", line 410, in _key_getter
    await matcher.reject(prompt)
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\internal\matcher.py", line 498, in reject
    raise RejectedException
nonebot.exception.RejectedException

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\message.py", line 153, in _check_matcher
    await _run_matcher(Matcher, bot, event, state, stack, dependency_cache)
> File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\message.py", line 202, in _run_matcher
    await matcher.run(bot, event, state, stack, dependency_cache)
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\internal\matcher.py", line 673, in run
    permission = await self.update_permission(bot, event)
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\internal\matcher.py", line 603, in update_permission
    return await updater(bot=bot, event=event, state=self.state, matcher=self)
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\dependencies\__init__.py", line 89, in __call__
    values = await self.solve(**kwargs)
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\dependencies\__init__.py", line 201, in solve
    values[field.name] = check_field_type(field, value)
  File "C:\MyProjectFolder\venv\lib\site-packages\nonebot\dependencies\utils.py", line 51, in check_field_type
    _, errs_ = field.validate(value, {}, loc=())
  File "pydantic\fields.py", line 829, in pydantic.fields.ModelField.validate
    assert cls is not None
AssertionError

请求解答

• matcher 实例化后还能否对其 permission_updater 进行修改
• 若可以, 正确的方法是什么?

环境信息

• System: Windows 11 21H2
• Python: 3.10.4
• nonebot2: 2.0.0b2

[yanyongyu]

matcher 实例化后修改permission updater会直接修改Matcher类的updater，影响到所有实例。

至于报错原因，看上去是因为ForwardRef的原因，你的代码中是否有 from __future__ import annotations这种语句，导致没有识别到具体的类，但是nb对这种情况会有Warning处理，也不应该报错才对。

补充：问题应该在这段代码的bot参数标注类型没能正确识别

async def __call__(self, bot: Bot) -> bool:

[Ailitonia]

matcher 实例化后修改permission updater会直接修改Matcher类的updater，影响到所有实例。

我注意到源码 Matcher.new 这里是是使用了 type 来建立了一个新的类并使用这个类来实例化 matcher:
https://github.com/nonebot/nonebot2/blob/049d9885746f6c553c223f8f54a2910999bcab99/nonebot/internal/matcher.py#L197-L199

所以即使是实例化后修改 permission_updater 导致修改 Matcher 类的 permission_updater, 影响的范围也仅限于插件中定义的这个 matcher 而不会是整个 bot 所有的 matcher 吗?

补充：问题应该在这段代码的bot参数标注类型没能正确识别

这个是 bug 吗, 是的话我就提 issue 了(

[yanyongyu]

permission_updater作用范围仅限于单个Matcher

你的报错问题我并没能复现，也看不出来问题在哪，你可以尝试debug一下list(test_permission_updater(self_id=bot.self_id).checkers)[0] 中的params是否正确

[Ailitonia]

昨天脑子不清醒没看出来, 这里是我的问题😂

permission_updater 应该是 T_PermissionUpdater, 中间修改 matcher.permission_updater 那里直接 call 了 test_permission_updater 导致传进去的是 Permission 了

另外 test_permission_updater 参数也应当改为允许的依赖参数

修改成这样就符合预期了:

from nonebot import on_command
from nonebot.matcher import Matcher
from nonebot.permission import Permission
from nonebot.adapters.onebot.v11.bot import Bot
from nonebot.message import run_preprocessor
from nonebot.params import ArgStr


class TestPermission:
    def __init__(self, self_id: str) -> None:
        self.self_id = self_id

    async def __call__(self, bot: Bot) -> bool:
        return bot.self_id == self.self_id


def test_permission_updater(bot: Bot) -> Permission:
    self_id = bot.self_id
    return Permission(TestPermission(self_id=self_id))


@run_preprocessor
async def unique_bot_responding_limit(matcher: Matcher):
    matcher.permission_updater(test_permission_updater)


test = on_command('test')


@test.got('arg', prompt='please input arg')
async def handle_arg(matcher: Matcher, arg: str = ArgStr('arg')):
    print(arg)
    await matcher.reject()