Download Telegram channel media using Telethon

telethon-download-channel-media.py

from telethon.sync import TelegramClient
from telethon.tl.functions.messages import GetDialogsRequest
from telethon.tl.functions.channels import GetFullChannelRequest
from telethon.tl.types import InputPeerEmpty
from telethon.errors.rpcerrorlist import SessionPasswordNeededError
from tqdm import tqdm

api_id = '12345678'
api_hash = '123456781234567812345678'
phone_number = '+380123456789'
PASS = 'your-password-if-enabled'

# Channel ID or name
channel_id = -100

def download_media(group, cl, name):
    messages = cl.get_messages(group, limit=2000)

    for message in tqdm(messages):
        message.download_media('./' + name + '/')

client = TelegramClient('downloading_session', api_id, api_hash)

client.connect()

if not client.is_user_authorized():
    client.send_code_request(phone_number)
    try:
        client.sign_in(phone_number, input(
            'Enter the code sent to your phone: '))
    except SessionPasswordNeededError as err:
        client.sign_in(password=PASS)

print('getting dialogs')
client.get_dialogs()
print('getting dialogs done')

print('starting client')
client.start()

channel = client(GetFullChannelRequest(channel_id))
print(channel.full_chat)

print('downloading media')
download_media(channel.full_chat, client, title)