aiogram/aiogram/utils/deep_linking.py
2019-11-29 23:27:19 +03:00

101 lines
3.1 KiB
Python

"""
Deep linking
Telegram bots have a deep linking mechanism, that allows for passing additional
parameters to the bot on startup. It could be a command that launches the bot — or
an auth token to connect the user's Telegram account to their account on some
external service.
You can read detailed description in the source:
https://core.telegram.org/bots#deep-linking
We have add some utils to get deep links more handy.
Basic link example:
.. code-block:: python
from aiogram.utils.deep_linking import get_start_link
link = await get_start_link('foo') # result: 'https://t.me/MyBot?start=foo'
Encoded link example:
.. code-block:: python
from aiogram.utils.deep_linking import get_start_link, decode_payload
link = await get_start_link('foo', encode=True) # result: 'https://t.me/MyBot?start=Zm9v'
# and decode it back:
payload = decode_payload('Zm9v') # result: 'foo'
"""
async def get_start_link(payload: str, encode=False) -> str:
"""
Use this method to handy get 'start' deep link with your payload.
If you need to encode payload or pass special characters - set encode as True
:param payload: args passed with /start
:param encode: encode payload with base64url
:return: link
"""
return await _create_link('start', payload, encode)
async def get_startgroup_link(payload: str, encode=False) -> str:
"""
Use this method to handy get 'startgroup' deep link with your payload.
If you need to encode payload or pass special characters - set encode as True
:param payload: args passed with /start
:param encode: encode payload with base64url
:return: link
"""
return await _create_link('startgroup', payload, encode)
async def _create_link(link_type, payload: str, encode=False):
bot = await _get_bot_user()
payload = filter_payload(payload)
if encode:
payload = encode_payload(payload)
return f'https://t.me/{bot.username}?{link_type}={payload}'
def encode_payload(payload: str) -> str:
""" Encode payload with URL-safe base64url. """
from base64 import urlsafe_b64encode
result: bytes = urlsafe_b64encode(payload.encode())
return result.decode()
def decode_payload(payload: str) -> str:
""" Decode payload with URL-safe base64url. """
from base64 import urlsafe_b64decode
result: bytes = urlsafe_b64decode(payload + '=' * (4 - len(payload) % 4))
return result.decode()
def filter_payload(payload: str) -> str:
""" Convert payload to text and search for not allowed symbols. """
import re
# convert to string
if not isinstance(payload, str):
payload = str(payload)
# search for not allowed characters
if re.search(r'[^_A-z0-9-]', payload):
message = ('Wrong payload! Only A-Z, a-z, 0-9, _ and - are allowed. '
'We recommend to encode parameters with binary and other '
'types of content.')
raise ValueError(message)
return payload
async def _get_bot_user():
""" Get current user of bot. """
from ..bot import Bot
bot = Bot.get_current()
return await bot.me