# Pyrogram - Telegram MTProto API Client Library for Python

# Copyright (C) 2017-2021 Dan <https://github.com/delivrance>

#

# This file is part of Pyrogram.

#

# Pyrogram is free software: you can redistribute it and/or modify

# it under the terms of the GNU Lesser General Public License as published

# by the Free Software Foundation, either version 3 of the License, or

# (at your option) any later version.

#

# Pyrogram 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 General Public License for more details.

#

# You should have received a copy of the GNU Lesser General Public License

# along with Pyrogram. If not, see <http://www.gnu.org/licenses/>.

from typing import Union

from pyrogram import raw

from pyrogram.scaffold import Scaffold

class GetChatMembersCount(Scaffold):

async def get_chat_members_count(

self,

chat_id: Union[int, str]

) -> int:

"""Get the number of members in a chat.

Parameters:

chat_id (``int`` | ``str``):

Unique identifier (int) or username (str) of the target chat.

Returns:

``int``: On success, the chat members count is returned.

Raises:

ValueError: In case a chat id belongs to user.

Example:

.. code-block:: python

count = app.get_chat_members_count("pyrogramchat")

print(count)

"""

peer = await self.resolve_peer(chat_id)

if isinstance(peer, raw.types.InputPeerChat):

r = await self.send(

raw.functions.messages.GetChats(

id=[peer.chat_id]

)

)

return r.chats[0].participants_count

elif isinstance(peer, raw.types.InputPeerChannel):

r = await self.send(

raw.functions.channels.GetFullChannel(

channel=peer

)

)

return r.full_chat.participants_count

else:

raise ValueError(f'The chat_id "{chat_id}" belongs to a user')