python-telegram-bot/telegram/ext/stringcommandhandler.py
2022-05-06 18:19:10 +02:00

106 lines
3.9 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 StringCommandHandler class."""
from typing import TYPE_CHECKING, Callable, List, Optional, TypeVar, Union
from telegram.utils.helpers import DefaultValue, DEFAULT_FALSE
from .handler import Handler
from .utils.types import CCT
if TYPE_CHECKING:
from telegram.ext import Dispatcher
RT = TypeVar('RT')
class StringCommandHandler(Handler[str, CCT]):
"""Handler class to handle string commands. Commands are string updates that start with ``/``.
The handler will add a ``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 :attr:`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 ``run_async`` to :obj:`True`, 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 (:obj:`callable`): The callback function for this handler. Will be called when
:attr:`check_update` has determined that an update should be processed by this handler.
Callback signature: ``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`.
run_async (:obj:`bool`): Determines whether the callback will run asynchronously.
Defaults to :obj:`False`.
Attributes:
command (:obj:`str`): The command this handler should listen for.
callback (:obj:`callable`): The callback function for this handler.
run_async (:obj:`bool`): Determines whether the callback will run asynchronously.
"""
__slots__ = ('command',)
def __init__(
self,
command: str,
callback: Callable[[str, CCT], RT],
run_async: Union[bool, DefaultValue] = DEFAULT_FALSE,
):
super().__init__(
callback,
run_async=run_async,
)
self.command = command
def check_update(self, update: object) -> Optional[List[str]]:
"""Determines whether an update should be passed to this handlers :attr:`callback`.
Args:
update (:obj:`object`): The incoming update.
Returns:
:obj:`bool`
"""
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,
dispatcher: 'Dispatcher',
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