refactor DB health-check

src/ez_lan_manager/pages/BasePage.py

@@ -4,12 +4,18 @@ from typing import *  # type: ignore
 
 from rio import Component, event, Spacer, Card, Container, Column, Row, TextStyle, Color, Text
 
-from src.ez_lan_manager import ConfigurationService
+from src.ez_lan_manager import ConfigurationService, DatabaseService
 from src.ez_lan_manager.components.DesktopNavigation import DesktopNavigation
 
 class BasePage(Component):
     content: Component
 
+    @event.periodic(5)
+    async def check_db_conn(self) -> None:
+        is_healthy = await self.session[DatabaseService].is_healthy()
+        if not is_healthy:
+            self.session.navigate_to("./db-error")
+
     @event.on_window_size_change
     async def on_window_size_change(self):
         await self.force_refresh()

src/ez_lan_manager/pages/DbErrorPage.py

@@ -15,12 +15,12 @@ class DbErrorPage(Component):
     async def on_window_size_change(self) -> None:
         await self.force_refresh()
 
-    # @event.on_mount
-    # async def retry_db_connect(self) -> None:
-    #     await self.session.set_title(f"{self.session[ConfigurationService].get_lan_info().name} - Fehler")
-    #     while not self.session[DatabaseService].is_connected:
-    #         await sleep(2)
-    #     self.session.navigate_to("./")
+    @event.on_mount
+    async def retry_db_connect(self) -> None:
+        await self.session.set_title(f"{self.session[ConfigurationService].get_lan_info().name} - Fehler")
+        while not await self.session[DatabaseService].is_healthy():
+            await sleep(2)
+        self.session.navigate_to("./")
 
     def build(self) -> Component:
         content = Card(

src/ez_lan_manager/services/DatabaseService.py

@@ -29,6 +29,17 @@ class DatabaseService:
         self._database_config = database_config
         self._connection_pool: Optional[aiomysql.Pool] = None
 
+    async def is_healthy(self) -> bool:
+        try:
+            async with self._connection_pool.acquire() as conn:
+                async with conn.cursor() as _:
+                    return True
+        except aiomysql.OperationalError:
+            return False
+        except Exception as e:
+            logger.error(f"Failed to acquire a connection: {e}")
+            return False
+
     async def init_db_pool(self) -> bool:
         logger.info(
             f"Connecting to database '{self._database_config.db_name}' on "
@@ -42,7 +53,7 @@ class DatabaseService:
                 password=self._database_config.db_password,
                 db=self._database_config.db_name,
                 minsize=1,
-                maxsize=20
+                maxsize=40
             )
         except aiomysql.OperationalError:
             return False
@@ -215,6 +226,7 @@ class DatabaseService:
                 except aiomysql.InterfaceError:
                     pool_init_result = await self.init_db_pool()
                     if not pool_init_result:
+                        print(self._connection_pool)
                         raise NoDatabaseConnectionError
                     return await self.get_news(dt_start, dt_end)
                 except Exception as e: