telegram/ext/_handlers/chatmemberhandler.py
#!/usr/bin/env python
#
# A library that provides a Python interface to the Telegram Bot API
# Copyright (C) 2015-2024
# Leandro Toledo de Souza <devs@python-telegram-bot.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser Public License for more details.
#
# You should have received a copy of the GNU Lesser Public License
# along with this program. If not, see [http://www.gnu.org/licenses/].
"""This module contains the ChatMemberHandler class."""
from typing import Final, Optional, TypeVar
from telegram import Update
from telegram._utils.defaultvalue import DEFAULT_TRUE
from telegram._utils.types import DVType
from telegram.ext._handlers.basehandler import BaseHandler
from telegram.ext._utils.types import CCT, HandlerCallback
RT = TypeVar("RT")
class ChatMemberHandler(BaseHandler[Update, CCT]):
"""Handler class to handle Telegram updates that contain a chat member update.
Warning:
When setting :paramref:`block` to :obj:`False`, you cannot rely on adding custom
attributes to :class:`telegram.ext.CallbackContext`. See its docs for more info.
Examples:
:any:`Chat Member Bot <examples.chatmemberbot>`
.. versionadded:: 13.4
Args:
callback (:term:`coroutine function`): The callback function for this handler. Will be
called when :meth:`check_update` has determined that an update should be processed by
this handler. Callback signature::
async def callback(update: Update, context: CallbackContext)
The return value of the callback is usually ignored except for the special case of
:class:`telegram.ext.ConversationHandler`.
chat_member_types (:obj:`int`, optional): Pass one of :attr:`MY_CHAT_MEMBER`,
:attr:`CHAT_MEMBER` or :attr:`ANY_CHAT_MEMBER` to specify if this handler should handle
only updates with :attr:`telegram.Update.my_chat_member`,
:attr:`telegram.Update.chat_member` or both. Defaults to :attr:`MY_CHAT_MEMBER`.
block (:obj:`bool`, optional): Determines whether the return value of the callback should
be awaited before processing the next handler in
:meth:`telegram.ext.Application.process_update`. Defaults to :obj:`True`.
.. seealso:: :wiki:`Concurrency`
Attributes:
callback (:term:`coroutine function`): The callback function for this handler.
chat_member_types (:obj:`int`): Optional. Specifies if this handler should handle
only updates with :attr:`telegram.Update.my_chat_member`,
:attr:`telegram.Update.chat_member` or both.
block (:obj:`bool`): Determines whether the return value of the callback should be
awaited before processing the next handler in
:meth:`telegram.ext.Application.process_update`.
"""
__slots__ = ("chat_member_types",)
MY_CHAT_MEMBER: Final[int] = -1
""":obj:`int`: Used as a constant to handle only :attr:`telegram.Update.my_chat_member`."""
CHAT_MEMBER: Final[int] = 0
""":obj:`int`: Used as a constant to handle only :attr:`telegram.Update.chat_member`."""
ANY_CHAT_MEMBER: Final[int] = 1
""":obj:`int`: Used as a constant to handle both :attr:`telegram.Update.my_chat_member`
and :attr:`telegram.Update.chat_member`."""
def __init__(
self,
callback: HandlerCallback[Update, CCT, RT],
chat_member_types: int = MY_CHAT_MEMBER,
block: DVType[bool] = DEFAULT_TRUE,
):
super().__init__(callback, block=block)
self.chat_member_types: Optional[int] = chat_member_types
def check_update(self, update: object) -> bool:
"""Determines whether an update should be passed to this handler's :attr:`callback`.
Args:
update (:class:`telegram.Update` | :obj:`object`): Incoming update.
Returns:
:obj:`bool`
"""
if isinstance(update, Update):
if not (update.my_chat_member or update.chat_member):
return False
if self.chat_member_types == self.ANY_CHAT_MEMBER:
return True
if self.chat_member_types == self.CHAT_MEMBER:
return bool(update.chat_member)
return bool(update.my_chat_member)
return False