Add support for bridging or responding to private chats with relaybot

example-config.yaml

@@ -163,6 +163,9 @@ bridge:
     image_as_file_size: 10
     # Maximum size of Telegram documents in megabytes to bridge.
     max_document_size: 100
+    # Whether or not created rooms should have federation enabled.
+    # If false, created portal rooms will never be federated.
+    federate_rooms: true
 
     # Whether to bridge Telegram bot messages as m.notices or m.texts.
     bot_messages_as_notices: true
@@ -185,7 +188,6 @@ bridge:
         # You might need to increase this on high-traffic bridge instances.
         cache_queue_length: 20
 
-
     # The formats to use when sending messages to Telegram via the relay bot.
     # Text msgtypes (m.text, m.notice and m.emote) support HTML, media msgtypes don't.
     #
@@ -258,6 +260,15 @@ bridge:
 
     # Options related to the message relay Telegram bot.
     relaybot:
+        private_chat:
+            # List of users to invite to the portal when someone starts a private chat with the bot.
+            # If empty, private chats with the bot won't create a portal.
+            invite: []
+            # Whether or not to bridge state change messages in relaybot private chats.
+            state_changes: true
+            # When private_chat_invite is empty, this message is sent to users /starting the
+            # relaybot. Telegram's "markdown" is supported.
+            message: This is a Matrix bridge relaybot and does not support direct chats
         # Whether or not to allow creating portals from Telegram.
         authless_portals: true
         # Whether or not to allow Telegram group admins to use the bot commands.

mautrix_telegram/abstract_user.py

@@ -405,10 +405,15 @@ class AbstractUser(ABC):
     async def update_message(self, original_update: UpdateMessage) -> None:
         update, sender, portal = self.get_message_details(original_update)
 
-        if self.is_bot and not portal.mxid:
-            self.log.debug(f"Ignoring message received by bot in unbridged chat %s",
-                           portal.tgid_log)
-            return
+        if self.is_bot:
+            if update.is_private:
+                if not config["bridge.relaybot.private_chat.invite"]:
+                    self.log.debug(f"Ignoring private message to bot from {sender.id}")
+                    return
+            elif not portal.mxid:
+                self.log.debug(
+                    f"Ignoring message received by bot in unbridged chat {portal.tgid_log}")
+                return
 
         if self.ignore_incoming_bot_events and self.relaybot and sender.id == self.relaybot.tgid:
             self.log.debug(f"Ignoring relaybot-sent message %s to %s", update, portal.tgid_log)

mautrix_telegram/bot.py

@@ -19,7 +19,7 @@ import logging
 from telethon.tl.patched import Message, MessageService
 from telethon.tl.types import (
     ChannelParticipantAdmin, ChannelParticipantCreator, ChatForbidden, ChatParticipantAdmin,
-    ChatParticipantCreator, InputChannel, InputUser, MessageActionChatAddUser,
+    ChatParticipantCreator, InputChannel, InputUser, MessageActionChatAddUser, PeerUser,
     MessageActionChatDeleteUser, MessageEntityBotCommand, PeerChannel, PeerChat, TypePeer,
     UpdateNewChannelMessage, UpdateNewMessage, MessageActionChatMigrateTo, User)
 from telethon.tl.functions.messages import GetChatsRequest, GetFullChatRequest
@@ -204,7 +204,12 @@ class Bot(AbstractUser):
         # chat is a normal group or a supergroup/channel when using the ID.
         if isinstance(message.to_id, PeerChannel):
             return reply(f"-100{message.to_id.channel_id}")
-        return reply(str(-message.to_id.chat_id))
+        elif isinstance(message.to_id, PeerChat):
+            return reply(str(-message.to_id.chat_id))
+        elif isinstance(message.to_id, PeerUser):
+            return reply(f"Your user ID is {message.from_id}.")
+        else:
+            return reply("Failed to find chat ID.")
 
     def match_command(self, text: str, command: str) -> bool:
         text = text.lower()
@@ -223,13 +228,20 @@ class Bot(AbstractUser):
 
     async def handle_command(self, message: Message) -> None:
         def reply(reply_text: str) -> Awaitable[Message]:
-            return self.client.send_message(message.to_id, reply_text, reply_to=message.id)
+            return self.client.send_message(message.chat_id, reply_text, reply_to=message.id)
 
         text = message.message
 
-        if self.match_command(text, "id"):
+        if self.match_command(text, "start"):
+            pcm = config["bridge.relaybot.private_chat.message"]
+            if pcm:
+                await reply(pcm)
+            return
+        elif self.match_command(text, "id"):
             await self.handle_command_id(message, reply)
             return
+        elif message.is_private:
+            return
 
         portal = po.Portal.get_by_entity(message.to_id)
 

mautrix_telegram/config.py

@@ -101,6 +101,7 @@ class Config(BaseBridgeConfig):
         copy("bridge.inline_images")
         copy("bridge.image_as_file_size")
         copy("bridge.max_document_size")
+        copy("bridge.federate_rooms")
 
         copy("bridge.bot_messages_as_notices")
         if isinstance(self["bridge.bridge_notices"], bool):
@@ -144,6 +145,9 @@ class Config(BaseBridgeConfig):
         if "bridge.relaybot" not in self:
             copy("bridge.authless_relaybot_portals", "bridge.relaybot.authless_portals")
         else:
+            copy("bridge.relaybot.private_chat.invite")
+            copy("bridge.relaybot.private_chat.state_changes")
+            copy("bridge.relaybot.private_chat.message")
             copy("bridge.relaybot.authless_portals")
             copy("bridge.relaybot.whitelist_group_admins")
             copy("bridge.relaybot.whitelist")

mautrix_telegram/matrix.py

@@ -138,7 +138,6 @@ class MatrixHandler(BaseMatrixHandler):
         portal = po.Portal.get_by_mxid(room_id)
         if user and await user.has_full_access(allow_bot=True) and portal:
             await portal.invite_telegram(inviter, user)
-            return
 
     async def handle_join(self, room_id: RoomID, user_id: UserID, event_id: EventID) -> None:
         user = await u.User.get_by_mxid(user_id).ensure_started()

mautrix_telegram/portal/base.py

@@ -147,7 +147,8 @@ class BasePortal(ABC):
 
     @property
     def has_bot(self) -> bool:
-        return bool(self.bot and self.bot.is_in_chat(self.tgid))
+        return ((bool(self.bot) and self.bot.is_in_chat(self.tgid))
+                or (self.peer_type == "user" and self.tg_receiver == self.bot.tgid))
 
     @property
     def main_intent(self) -> IntentAPI:

mautrix_telegram/portal/matrix.py

@@ -90,6 +90,8 @@ class PortalMatrix(BasePortal, MautrixBasePortal, ABC):
                                          **kwargs: Any) -> None:
         if not self.has_bot:
             return
+        elif self.peer_type == "user" and not config["bridge.relaybot.private_chat.state_changes"]:
+            return
         async with self.send_lock(self.bot.tgid):
             message = await self._get_state_change_message(event, user, **kwargs)
             if not message:

mautrix_telegram/portal/metadata.py

@@ -164,7 +164,8 @@ class PortalMetadata(BasePortal, ABC):
                 AddChatUserRequest(chat_id=self.tgid, user_id=puppet.tgid, fwd_limit=0))
         elif self.peer_type == "channel":
             await source.client(InviteToChannelRequest(channel=self.peer, users=[puppet.tgid]))
-        else:
+        # We don't care if there are invites for private chat portals with the relaybot.
+        elif not self.bot or self.tg_receiver != self.bot.tgid:
             raise ValueError("Invalid peer type for Telegram user invite")
 
     async def sync_matrix_members(self) -> None:
@@ -293,6 +294,10 @@ class PortalMetadata(BasePortal, ABC):
         if not direct:
             users, participants = await self._get_users(user, entity)
             self._participants_to_power_levels(participants, power_levels)
+        elif self.tg_receiver == self.bot.tgid:
+            invites = config["bridge.relaybot.private_chat.invite"]
+            for invite in invites:
+                power_levels.users[invite] = 100
         initial_state = [{
             "type": EventType.ROOM_POWER_LEVELS.serialize(),
             "content": power_levels.serialize(),
@@ -302,11 +307,15 @@ class PortalMetadata(BasePortal, ABC):
                 "type": "m.room.related_groups",
                 "content": {"groups": [config["appservice.community_id"]]},
             })
+        creation_content = {}
+        if not config["bridge.federate_rooms"]:
+            creation_content["m.federate"] = False
 
         room_id = await self.main_intent.create_room(alias_localpart=alias, preset=preset,
                                                      is_direct=direct, invitees=invites or [],
                                                      name=self.title, topic=self.about,
-                                                     initial_state=initial_state)
+                                                     initial_state=initial_state,
+                                                     creation_content=creation_content)
         if not room_id:
             raise Exception(f"Failed to create room")