Add [localization]: connect i18n middleware to the bot

src/bot/__init__.py

@@ -1,8 +1,11 @@
 __all__ = ["start_bot"]
 
 
+from pathlib import Path
+
 from aiogram import Bot, Dispatcher
 from aiogram.fsm.storage.redis import RedisStorage
+from aiogram.utils.i18n import I18n
 from loguru import logger as loguru_logger
 from redis.asyncio.client import Redis
 from sqlalchemy.ext.asyncio import async_sessionmaker
@@ -16,6 +19,7 @@ async def start_bot(
     bot_token: str,
     redis_protocol: Redis,
     session_maker: async_sessionmaker,
+    i18n_domain: str,
 ) -> None:
     """
     Start Telegram bot.
@@ -24,6 +28,7 @@ async def start_bot(
         bot_token (str): Telegram API bot token.
         redis_client (Redis): async configured client for redis.
         session_maker (AsyncSession): async database session maker.
+        i18n_domain (str): the bot locales domain.
     """
     bot = Bot(bot_token)
 
@@ -31,13 +36,15 @@ async def start_bot(
         storage=RedisStorage(redis=redis_protocol),
     )
 
+    locales_dir = Path(".") / "src" / "locales"
+    i18n = I18n(path=locales_dir, default_locale="ru", domain=i18n_domain)
+
     connect_middlewares(
         dispatcher=dispatcher,
         session_maker=session_maker,
+        i18n=i18n,
     )
-    loguru_logger.debug(
-        "Middlewares have been successfully connected."
-    )
+    loguru_logger.debug("Middlewares have been successfully connected.")
 
     include_routers(dispatcher)
     loguru_logger.debug("Routers have been successfully included.")

src/bot/middlewares/__init__.py

@@ -2,9 +2,11 @@ __all__ = ["connect_middlewares"]
 
 
 from aiogram import Dispatcher
+from aiogram.utils.i18n import I18n
 from sqlalchemy.ext.asyncio import async_sessionmaker
 
 from .database import DatabaseSessionMiddleware
+from .i18n import I18nMiddleware
 from .registration import RegistrationMiddleware
 from .telegram_user import TelegramUserMiddleware
 
@@ -12,6 +14,7 @@ from .telegram_user import TelegramUserMiddleware
 def connect_middlewares(
     dispatcher: Dispatcher,
     session_maker: async_sessionmaker,
+    i18n: I18n,
 ) -> None:
     """
     Connecting all middleware for the dispatcher.
@@ -19,10 +22,12 @@ def connect_middlewares(
     1. DatabaseSessionMiddleware (outer): provides a session.
     2. TelegramUserMiddleware (outer): uses session to get a user.
     3. RegistrationMiddleware (outer): uses user to check status.
+    4. I18nMiddleware (inter): uses session to get user's locale code.
 
     Args:
         dispatcher (Dispatcher): bot dispatcher.
         session_maker (async_sessionmaker): database sessionmaker.
+        i18n (I18n): aiogram bot i18n object.
     """
     dispatcher.update.outer_middleware(
         DatabaseSessionMiddleware(session_maker=session_maker)
@@ -31,3 +36,5 @@ def connect_middlewares(
     dispatcher.update.outer_middleware(TelegramUserMiddleware())
 
     dispatcher.update.outer_middleware(RegistrationMiddleware())
+
+    dispatcher.update.middleware(I18nMiddleware(i18n=i18n))

src/config/settings.py

@@ -31,6 +31,10 @@ class Settings(BaseSettings):
          Enable SQLAlchemy engine echo.
          Defaults to True.
 
+        bot_i18n_domain (str):
+         The bot locales i18n domain.
+         Defaults to "messages".
+
         redis_host (str):
          Redis host name.
          Defaults to "redis"
@@ -70,6 +74,8 @@ class Settings(BaseSettings):
             f"{self.postgres_port}/{self.postgres_name}"
         )
 
+    bot_i18n_domain: str = Field(frozen=True, default="messages")
+
     redis_host: str = Field(frozen=True, default="redis")
     redis_port: int = Field(frozen=True, default=6379)
 

src/main.py

@@ -34,9 +34,7 @@ async def process_args() -> None:
 
     args = parser.parse_args()
 
-    loguru_logger.debug(
-        f"List of arguments passed to the program: {args}"
-    )
+    loguru_logger.debug(f"List of arguments passed to the program: {args}")
 
     match args.db:
         case "create":
@@ -48,9 +46,7 @@ async def process_args() -> None:
             await drop_db(engine)
             exit(0)
         case "migrate":
-            loguru_logger.debug(
-                "Attempt to make database migrations..."
-            )
+            loguru_logger.debug("Attempt to make database migrations...")
             exit(0)
 
 
@@ -71,6 +67,7 @@ async def main() -> None:
         bot_token=settings.bot_token,
         redis_protocol=redis_protocol,
         session_maker=session_maker,
+        i18n_domain=settings.bot_i18n_domain,
     )