#238 Deep linking feature

[Olegt0rr]

Description

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:

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:

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 after receiving
payload = decode_payload('Zm9v')  # result: 'foo'

It's also works with get_startgroup_link util.

Fixes #238

Type of change

• Documentation (typos, code examples or any documentation update)
• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

• test_deep_linking.TestDeepLinking