telegram/ext/_handlers/stringcommandhandler.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 StringCommandHandler class."""
from typing import TYPE_CHECKING, Any, List, Optional
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, RT, HandlerCallback
if TYPE_CHECKING:
from telegram.ext import Application
class StringCommandHandler(BaseHandler[str, CCT]):
"""Handler class to handle string commands. Commands are string updates that start with
``/``. The handler will add a :obj:`list` to the
:class:`CallbackContext` named :attr:`CallbackContext.args`. It will contain a list of strings,
which is the text following the command split on single whitespace characters.
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:
command (:obj:`str`): The command this handler should listen for.
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: str, 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:
command (:obj:`str`): The command this handler should listen for.
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__ = ("command",)
def __init__(
self,
command: str,
callback: HandlerCallback[str, CCT, RT],
block: DVType[bool] = DEFAULT_TRUE,
):
super().__init__(callback, block=block)
self.command: str = command
def check_update(self, update: object) -> Optional[List[str]]:
"""Determines whether an update should be passed to this handler's :attr:`callback`.
Args:
update (:obj:`object`): The incoming update.
Returns:
List[:obj:`str`]: List containing the text command split on whitespace.
"""
if isinstance(update, str) and update.startswith("/"):
args = update[1:].split(" ")
if args[0] == self.command:
return args[1:]
return None
def collect_additional_context(
self,
context: CCT,
update: str, # noqa: ARG002
application: "Application[Any, CCT, Any, Any, Any, Any]", # noqa: ARG002
check_result: Optional[List[str]],
) -> None:
"""Add text after the command to :attr:`CallbackContext.args` as list, split on single
whitespaces.
"""
context.args = check_result