I’m trying to run this first code snippet provided by the Telethon documentation. But, after multiple problems (here and here), I ended up with this modified version:
import os
import sys
from telethon.sync import TelegramClient, events
# import nest_asyncio
# nest_asyncio.apply()
session_name = "<session_name>"
api_id = <api_id>
api_hash = "<api_hash>"
os.chdir(sys.path[0])
if f"{session_name}.session" in os.listdir():
os.remove(f"{session_name}.session")
async with TelegramClient(session_name, api_id, api_hash) as client:
client.send_message('me', 'Hello, myself!')
print(client.download_profile_photo('me'))
@client.on(events.NewMessage(pattern='(?i).*Hello'))
async def handler(event):
await event.reply('Hey!')
client.run_until_disconnected()
However now I’m getting these warnings:
usr/local/lib/python3.7/site-packages/ipykernel_launcher.py:23: RuntimeWarning: coroutine 'MessageMethods.send_message' was never awaited RuntimeWarning: Enable tracemalloc to get the object allocation traceback /usr/local/lib/python3.7/site-packages/ipykernel_launcher.py:24: RuntimeWarning: coroutine 'DownloadMethods.download_profile_photo' was never awaited RuntimeWarning: Enable tracemalloc to get the object allocation traceback /usr/local/lib/python3.7/site-packages/ipykernel_launcher.py:30: RuntimeWarning: coroutine 'UpdateMethods._run_until_disconnected' was never awaited RuntimeWarning: Enable tracemalloc to get the object allocation traceback
when running the code on Jupyter. Now here are my questions:
- what those warning messages mean and how should I address them?
- what is the expected result of this code if working properly? Should I receive a message in Telegram or something? Because I don’t recive any messages other than the signin code.
- What does the
@
symbol at the beginning of the@client.on...
line mean? what does that line is supposed to do? From this line onwards I do not understand the code. Would appreciate if you could help me understand it.
2
Answers
Jupyter will run the
asyncio
event loop so that you can useasync for / with / await
outside of anasync def
. This conflicts with Telethon’s.sync
magic which you should try to avoid when using Jupyter, IPython, or similar.To fix your code:
If you want code to run anywhere (Jupyter, Python shell, normal run), just be sure to do everything inside
async def
:Just add
await
theclient.send_message('me', 'Hello, myself!')
to solve that error and print afterdownload_profile_photo
has done its work downloads an image tolocalhost
so that may be why you don’t see anything. You should read telethon documentation thoroughly and also how to use photo downloads correctlyAll the calls to the client have a delay and should always be awaited so that your code doesn’t get blocked. You should read the asyncio tutorial
The correct code would be:
The @ is a decorator and you should read the PEP related to decorators, but in short words, they execute a function before yours.
In this case
@client.on(events.NewMessage
means:When there is a new event that happens to be a message that matches the pattern specified handle it with this function called
handler