python-telegram-bot/telegram/ext/_stringregexhandler.py
Bibo-Joshi 42eaa67fd5 Switch to asyncio (#2731)
Co-authored-by: tsnoam <tsnoam@gmail.com>
Co-authored-by: Harshil <37377066+harshil21@users.noreply.github.com>
Co-authored-by: Poolitzer <25934244+Poolitzer@users.noreply.github.com>
2022-05-06 18:19:15 +02:00

114 lines
4.3 KiB
Python

#!/usr/bin/env python
#
# A library that provides a Python interface to the Telegram Bot API
# Copyright (C) 2015-2022
# 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 StringRegexHandler class."""
import re
from typing import TYPE_CHECKING, Match, Optional, Pattern, TypeVar, Union
from telegram._utils.types import DVInput
from telegram.ext import Handler
from telegram.ext._utils.types import CCT, HandlerCallback
from telegram._utils.defaultvalue import DEFAULT_TRUE
if TYPE_CHECKING:
from telegram.ext import Application
RT = TypeVar('RT')
class StringRegexHandler(Handler[str, CCT]):
"""Handler class to handle string updates based on a regex which checks the update content.
Read the documentation of the :mod:`re` module for more information. The :func:`re.match`
function is used to determine if an update should be handled by this handler.
Note:
This handler is not used to handle Telegram :class:`telegram.Update`, but strings manually
put in the queue. For example to send messages with the bot using command line or API.
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:
pattern (:obj:`str` | :func:`re.Pattern <re.compile>`): The regex pattern.
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`.
Attributes:
pattern (:obj:`str` | :func:`re.Pattern <re.compile>`): The regex pattern.
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__ = ('pattern',)
def __init__(
self,
pattern: Union[str, Pattern],
callback: HandlerCallback[str, CCT, RT],
block: DVInput[bool] = DEFAULT_TRUE,
):
super().__init__(callback, block=block)
if isinstance(pattern, str):
pattern = re.compile(pattern)
self.pattern = pattern
def check_update(self, update: object) -> Optional[Match]:
"""Determines whether an update should be passed to this handler's :attr:`callback`.
Args:
update (:obj:`object`): The incoming update.
Returns:
:obj:`None` | :obj:`re.match`
"""
if isinstance(update, str):
match = re.match(self.pattern, update)
if match:
return match
return None
def collect_additional_context(
self,
context: CCT,
update: str,
application: 'Application',
check_result: Optional[Match],
) -> None:
"""Add the result of ``re.match(pattern, update)`` to :attr:`CallbackContext.matches` as
list with one element.
"""
if self.pattern and check_result:
context.matches = [check_result]