Added support of "startapp" deep links (#1648)

* Added "startapp" deep link support

* Remove link_type param, added create_startapp_link method

* Write tests for create_startapp_link method

* Refactor with black & isort

* Added CHANGELOG

CHANGES/1648.feature.rst

@@ -0,0 +1,2 @@
+Added new method to utils/deep_linking.py module to creating "startapp" deep links, see also 
+https://core.telegram.org/api/links#main-mini-app-links

aiogram/utils/deep_linking.py

@@ -3,6 +3,7 @@ from __future__ import annotations
 __all__ = [
     "create_start_link",
     "create_startgroup_link",
+    "create_startapp_link",
     "create_deep_link",
     "create_telegram_link",
     "encode_payload",
@@ -77,9 +78,37 @@ async def create_startgroup_link(
     )
 
 
+async def create_startapp_link(
+    bot: Bot,
+    payload: str,
+    encode: bool = False,
+    encoder: Optional[Callable[[bytes], bytes]] = None,
+) -> str:
+    """
+    Create 'startapp' deep link with your payload.
+
+    If you need to encode payload or pass special characters -
+        set encode as True
+
+    :param bot: bot instance
+    :param payload: args passed with /start
+    :param encode: encode payload with base64url or custom encoder
+    :param encoder: custom encoder callable
+    :return: link
+    """
+    username = (await bot.me()).username
+    return create_deep_link(
+        username=cast(str, username),
+        link_type="startapp",
+        payload=payload,
+        encode=encode,
+        encoder=encoder,
+    )
+
+
 def create_deep_link(
     username: str,
-    link_type: Literal["start", "startgroup"],
+    link_type: Literal["start", "startgroup", "startapp"],
     payload: str,
     encode: bool = False,
     encoder: Optional[Callable[[bytes], bytes]] = None,

tests/test_utils/test_deep_linking.py

@@ -1,6 +1,10 @@
 import pytest
 
-from aiogram.utils.deep_linking import create_start_link, create_startgroup_link
+from aiogram.utils.deep_linking import (
+    create_start_link,
+    create_startapp_link,
+    create_startgroup_link,
+)
 from aiogram.utils.payload import decode_payload, encode_payload
 from tests.mocked_bot import MockedBot
 
@@ -44,6 +48,10 @@ class TestDeepLinking:
         link = await create_startgroup_link(bot, payload)
         assert link == f"https://t.me/tbot?startgroup={payload}"
 
+    async def test_get_startapp_link(self, bot: MockedBot, payload: str):
+        link = await create_startapp_link(bot, payload)
+        assert link == f"https://t.me/tbot?startapp={payload}"
+
     async def test_filter_encode_and_decode(self, payload: str):
         encoded = encode_payload(payload)
         decoded = decode_payload(encoded)
@@ -85,6 +93,15 @@ class TestDeepLinking:
 
         assert link == f"https://t.me/tbot?start={encoded_payload}"
 
+    async def test_get_startapp_link_with_encoding(self, bot: MockedBot, wrong_payload: str):
+        # define link
+        link = await create_startapp_link(bot, wrong_payload, encode=True)
+
+        # define reference link
+        encoded_payload = encode_payload(wrong_payload)
+
+        assert link == f"https://t.me/tbot?startapp={encoded_payload}"
+
     async def test_64_len_payload(self, bot: MockedBot):
         payload = "p" * 64
         link = await create_start_link(bot, payload)