python-telegram-bot/telegram/ext/_handlers/messagehandler.py
2024-09-14 08:16:39 +02:00

111 lines
4.6 KiB
Python

#!/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 MessageHandler class."""
from typing import TYPE_CHECKING, Any, Dict, List, Optional, TypeVar, Union
from telegram import Update
from telegram._utils.defaultvalue import DEFAULT_TRUE
from telegram._utils.types import DVType
from telegram.ext import filters as filters_module
from telegram.ext._handlers.basehandler import BaseHandler
from telegram.ext._utils.types import CCT, HandlerCallback
if TYPE_CHECKING:
from telegram.ext import Application
RT = TypeVar("RT")
class MessageHandler(BaseHandler[Update, CCT, RT]):
"""Handler class to handle Telegram messages. They might contain text, media or status
updates.
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.
Args:
filters (:class:`telegram.ext.filters.BaseFilter`): A filter inheriting from
:class:`telegram.ext.filters.BaseFilter`. Standard filters can be found in
:mod:`telegram.ext.filters`. Filters can be combined using bitwise
operators (& for and, | for or, ~ for not). Passing :obj:`None` is a shortcut
to passing :class:`telegram.ext.filters.ALL`.
.. seealso:: :wiki:`Advanced Filters <Extensions---Advanced-Filters>`
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`.
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:
filters (:class:`telegram.ext.filters.BaseFilter`): Only allow updates with these Filters.
See :mod:`telegram.ext.filters` for a full list of all available filters.
callback (:term:`coroutine function`): The callback function for this handler.
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__ = ("filters",)
def __init__(
self: "MessageHandler[CCT, RT]",
filters: Optional[filters_module.BaseFilter],
callback: HandlerCallback[Update, CCT, RT],
block: DVType[bool] = DEFAULT_TRUE,
):
super().__init__(callback, block=block)
self.filters: filters_module.BaseFilter = (
filters if filters is not None else filters_module.ALL
)
def check_update(self, update: object) -> Optional[Union[bool, Dict[str, List[Any]]]]:
"""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):
return self.filters.check_update(update) or False
return None
def collect_additional_context(
self,
context: CCT,
update: Update, # noqa: ARG002
application: "Application[Any, CCT, Any, Any, Any, Any]", # noqa: ARG002
check_result: Optional[Union[bool, Dict[str, object]]],
) -> None:
"""Adds possible output of data filters to the :class:`CallbackContext`."""
if isinstance(check_result, dict):
context.update(check_result)