Support getting any entity by just their positive ID

telethon/sessions/memory.py

@@ -1,9 +1,8 @@
 from enum import Enum
 
-from .. import utils
 from .abstract import Session
+from .. import utils
 from ..tl import TLObject
-
 from ..tl.types import (
     PeerUser, PeerChat, PeerChannel,
     InputPeerUser, InputPeerChat, InputPeerChannel,
@@ -148,10 +147,19 @@ class MemorySession(Session):
         except StopIteration:
             pass
 
-    def get_entity_rows_by_id(self, id):
+    def get_entity_rows_by_id(self, id, exact=True):
         try:
+            if exact:
                 return next((id, hash) for found_id, hash, _, _, _
                             in self._entities if found_id == id)
+            else:
+                ids = (
+                    utils.get_peer_id(PeerUser(id)),
+                    utils.get_peer_id(PeerChat(id)),
+                    utils.get_peer_id(PeerChannel(id))
+                )
+                return next((id, hash) for found_id, hash, _, _, _
+                            in self._entities if found_id in ids)
         except StopIteration:
             pass
 
@@ -167,6 +175,9 @@ class MemorySession(Session):
             # Not a TLObject or can't be cast into InputPeer
             if isinstance(key, TLObject):
                 key = utils.get_peer_id(key)
+                exact = True
+            else:
+                exact = False
 
         result = None
         if isinstance(key, str):
@@ -178,8 +189,8 @@ class MemorySession(Session):
                 if username:
                     result = self.get_entity_rows_by_username(username)
 
-        if isinstance(key, int):
+        elif isinstance(key, int):
-            result = self.get_entity_rows_by_id(key)
+            result = self.get_entity_rows_by_id(key, exact)
 
         if not result and isinstance(key, str):
             result = self.get_entity_rows_by_name(key)

telethon/sessions/sqlalchemy.py

@@ -4,12 +4,13 @@ try:
     import sqlalchemy as sql
 except ImportError:
     sql = None
-    pass
-
-from ..crypto import AuthKey
-from ..tl.types import InputPhoto, InputDocument
 
 from .memory import MemorySession, _SentFileType
+from .. import utils
+from ..crypto import AuthKey
+from ..tl.types import (
+    InputPhoto, InputDocument, PeerUser, PeerChat, PeerChannel
+)
 
 LATEST_VERSION = 1
 
@@ -201,8 +202,18 @@ class AlchemySession(MemorySession):
                              self.Entity.name == key).one_or_none()
         return row.id, row.hash if row else None
 
-    def get_entity_rows_by_id(self, key):
+    def get_entity_rows_by_id(self, key, exact=True):
-        row = self._db_query(self.Entity, self.Entity.id == key).one_or_none()
+        if exact:
+            query = self._db_query(self.Entity, self.Entity.id == key)
+        else:
+            ids = (
+                utils.get_peer_id(PeerUser(key)),
+                utils.get_peer_id(PeerChat(key)),
+                utils.get_peer_id(PeerChannel(key))
+            )
+            query = self._db_query(self.Entity, self.Entity.id in ids)
+
+        row = query.one_or_none()
         return row.id, row.hash if row else None
 
     def get_file(self, md5_digest, file_size, cls):

telethon/sessions/sqlite.py

@@ -6,9 +6,10 @@ from os.path import isfile as file_exists
 from threading import Lock, RLock
 
 from .memory import MemorySession, _SentFileType
+from .. import utils
 from ..crypto import AuthKey
 from ..tl.types import (
-    InputPhoto, InputDocument
+    InputPhoto, InputDocument, PeerUser, PeerChat, PeerChannel
 )
 
 EXTENSION = '.session'
@@ -282,9 +283,19 @@ class SQLiteSession(MemorySession):
         return self._fetchone_entity(
             'select id, hash from entities where name=?', (name,))
 
-    def get_entity_rows_by_id(self, id):
+    def get_entity_rows_by_id(self, id, exact=True):
+        if exact:
             return self._fetchone_entity(
                 'select id, hash from entities where id=?', (id,))
+        else:
+            ids = (
+                utils.get_peer_id(PeerUser(id)),
+                utils.get_peer_id(PeerChat(id)),
+                utils.get_peer_id(PeerChannel(id))
+            )
+            return self._fetchone_entity(
+                'select id, hash from entities where id in (?,?,?)', ids
+            )
 
     # File processing
 

telethon/telegram_client.py

@@ -2272,23 +2272,21 @@ class TelegramClient(TelegramBareClient):
                 return InputPeerSelf()
             return utils.get_input_peer(self._get_entity_from_string(peer))
 
-        if isinstance(peer, int):
+        if not isinstance(peer, int):
-            peer, kind = utils.resolve_id(peer)
-            peer = kind(peer)
-
             try:
-            is_peer = peer.SUBCLASS_OF_ID == 0x2d45687  # crc32(b'Peer')
+                if peer.SUBCLASS_OF_ID != 0x2d45687:  # crc32(b'Peer')
-            if not is_peer:
                     return utils.get_input_peer(peer)
             except (AttributeError, TypeError):
-            is_peer = False
+                peer = None
 
-        if not is_peer:
+        if not peer:
             raise TypeError(
                 'Cannot turn "{}" into an input entity.'.format(peer)
             )
 
-        # Not found, look in the dialogs with the hope to find it.
+        # Add the mark to the peers if the user passed a Peer (not an int)
+        # Look in the dialogs with the hope to find it.
+        mark = not isinstance(peer, int)
         target_id = utils.get_peer_id(peer)
         req = GetDialogsRequest(
             offset_date=None,
@@ -2299,12 +2297,20 @@ class TelegramClient(TelegramBareClient):
         while True:
             result = self(req)
             entities = {}
+            if mark:
                 for x in itertools.chain(result.users, result.chats):
                     x_id = utils.get_peer_id(x)
                     if x_id == target_id:
                         return utils.get_input_peer(x)
                     else:
                         entities[x_id] = x
+            else:
+                for x in itertools.chain(result.users, result.chats):
+                    if x.id == target_id:
+                        return utils.get_input_peer(x)
+                    else:
+                        entities[utils.get_peer_id(x)] = x
+
             if len(result.dialogs) < req.limit:
                 break