Add possibility to include router via string

Makefile

@@ -104,7 +104,7 @@ test:
 .PHONY: test-coverage
 test-coverage:
 	mkdir -p reports/tests/
-	$(py) pytest --cov=aiogram --cov-config .coveragerc --html=reports/tests/index.html tests/
+	$(py) pytest --cov=aiogram --cov-config .coveragerc --html=reports/tests/index.html -p no:warnings tests/
 	$(py) coverage html -d reports/coverage
 
 # =================================================================================================

aiogram/dispatcher/router.py

@@ -1,8 +1,9 @@
 from __future__ import annotations
 
-from typing import Any, Dict, List, Optional
+from typing import Any, Dict, List, Optional, Union
 
 from ..api.types import Chat, Update, User
+from ..utils.imports import import_module
 from .event.observer import EventObserver, SkipHandler, TelegramEventObserver
 from .filters import BUILTIN_FILTERS
 
@@ -76,7 +77,13 @@ class Router:
 
         self._parent_router = router
 
-    def include_router(self, router: Router) -> Router:
+    def include_router(self, router: Union[Router, str]) -> Router:
+        if isinstance(router, str):
+            router = import_module(router)
+        if not isinstance(router, Router):
+            raise ValueError(
+                f"router should be instance of Router not {type(router).__class__.__name__}"
+            )
         router.parent_router = self
         self.sub_routers.append(router)
         return router

aiogram/utils/imports.py

@@ -0,0 +1,23 @@
+import importlib
+from typing import Any
+
+
+def import_module(target: str) -> Any:
+    if not isinstance(target, str):
+        raise ValueError(f"Target should be string not {type(target).__class__.__name__}")
+
+    module_name, _, attr_name = target.partition(":")
+    if not module_name or not attr_name:
+        raise ValueError(f'Import string "{target}" must be in format "<module>:<attribute>"')
+
+    try:
+        module = importlib.import_module(module_name)
+    except ImportError:
+        raise ValueError(f'Could not import module "{module_name}".')
+
+    try:
+        attribute = getattr(module, attr_name)
+    except AttributeError:
+        raise ValueError(f'Module "{module_name}" has no attribute "{attr_name}"')
+
+    return attribute

handlers.py

@@ -0,0 +1,13 @@
+from typing import Any
+
+from aiogram import Router
+from aiogram.api.methods import SendMessage
+from aiogram.dispatcher.handler.message import MessageHandler
+
+router = Router()
+
+
+@router.message_handler(commands=["test"])
+class MyHandler(MessageHandler):
+    async def handle(self) -> Any:
+        return SendMessage(chat_id=self.chat.id, text="<b>PASS</b>")

tests/test_dispatcher/test_router.py

@@ -20,6 +20,8 @@ from aiogram.api.types import (
 from aiogram.dispatcher.event.observer import SkipHandler
 from aiogram.dispatcher.router import Router
 
+importable_router = Router()
+
 
 class TestRouter:
     def test_including_routers(self):
@@ -50,6 +52,15 @@ class TestRouter:
         assert router3.parent_router is router2
         assert router3.sub_routers == []
 
+    def test_include_router_by_string(self):
+        router = Router()
+        router.include_router("tests.test_dispatcher.test_router:importable_router")
+
+    def test_include_router_by_string_bad_type(self):
+        router = Router()
+        with pytest.raises(ValueError, match=r"router should be instance of Router"):
+            router.include_router("tests.test_dispatcher.test_router:TestRouter")
+
     def test_observers_config(self):
         router = Router()
         assert router.update_handler.handlers

tests/test_utils/test_imports.py

@@ -0,0 +1,29 @@
+import pytest
+
+import aiogram
+from aiogram.utils.imports import import_module
+
+
+class TestImports:
+    def test_bad_type(self):
+        with pytest.raises(ValueError, match=r"Target should be string not"):
+            import_module(42)
+
+    @pytest.mark.parametrize("value", ["module", "module:", ":attribute"])
+    def test_bad_format(self, value):
+        with pytest.raises(ValueError, match='must be in format "<module>:<attribute>"'):
+            import_module(value)
+
+    @pytest.mark.parametrize("value", ["module", "aiogram.KABOOM", "aiogram.KABOOM.TEST"])
+    def test_bad_value(self, value):
+        with pytest.raises(ValueError, match="Could not import module"):
+            import_module(f"{value}:attribute")
+
+    def test_has_no_attribute(self):
+        with pytest.raises(ValueError, match="has no attribute"):
+            import_module("aiogram:KABOOM")
+
+    def test_imported(self):
+        value = import_module("aiogram:__version__")
+        isinstance(value, str)
+        assert value == aiogram.__version__