Get username from local session Telethon - python-3.x

Question

I'm using telethon library to crawl some telegram channels. While crawling, i need to resolve many join links, usernames and channel ids. To resolve these items, i used method client.get_entity() but after a while telegram servers banned my crawler for resolving too many usernames. I searched around and found from this issue, i should use get_input_entity() instead of get_entity(). Actually telethon saves entities inside a local SQLite file and whenever a call to get_input_entity() is made, it first searches the local SQLite database, if no match found it then sends request to telegram servers. So far so good but i have two problems with this approach:
get_input_entity() just returns two attributes: ID and hash but there are other columns like username, phone and name in the SQLite database. I need a method to not just return ID and hash, but to return other columns too.
I need to control the number of resolve requests sent to telegram server but get_input_entity() sends request to telegram servers whenever founds no match in the local database. The problem is that i can't control this method when to request telegram servers. Actually i need a boolean argument for this method indicating whether or not the method should send a request to telegram servers when no match in the local database is found.
I read some of the telethon source codes, mainly get_input_entity() and wrote my own version of get_input_entity():
def my_own_get_input_entity(self, target, with_info: bool = False):
if self._client:
if target in ('me', 'self'):
return types.InputPeerSelf()
def get_info():
nonlocal self, result
res_id = 0
if isinstance(result, InputPeerChannel):
res_id = result.channel_id
elif isinstance(result, InputPeerChat):
res_id = result.chat_id
elif isinstance(result, InputPeerUser):
res_id = result.user_id
return self._sqlite_session._execute(
'select username, name from entities where id = ?', res_id
)
try:
result = self._client.session.get_input_entity(target)
info = get_info() if with_info else None
return result, info
except ValueError:
record_current_time()
try:
# when we are here, we are actually going to
# send request to telegram servers
if not check_if_appropriate_time_elapsed_from_last_telegram_request():
return None
result = self._client.get_input_entity(target)
info = get_info() if with_info else None
return result, info
except ChannelPrivateError:
pass
except ValueError:
pass
except Exception:
pass
But my code is somehow performance problematic because it makes redundant queries to SQLite database. For example, if the target is actually an entity inside the local database and with_info is True, it first queries the local database in line self._client.session.get_input_entity(target) and checks if with_info is True, then queries the database again to get username and name columns. In another situation, if target is not found inside the local database, calling self._client.get_input_entity(target) makes a redundant call to local database.
Knowing these performance issues, i delved deeper in telethon source codes but as i don't know much about asyncio, i couldn't write any better code than above.
Any ideas how to solve the problems?

Answer 1

client.session.get_input_entity will make no API call (it can't), and fails if there is no match in the local database, which is probably the behaviour you want.
You can, for now, access the client.session._conn private attribute. It's a sqlite3.Connection object so you can use that to make all the queries you want. Note that this is prone to breaking since you're accessing a private member although no changes are expected soon. Ideally, you should subclass the session file to suit your needs. See Session Files in the documentation.