"feat: Refactor database connection in app.py"

backend/app/app.py

@@ -138,31 +138,38 @@ def load_user(user_id):
     Robuster User-Loader mit Error-Handling für Schema-Probleme.
     """
     try:
+        # user_id von Flask-Login ist immer ein String - zu Integer konvertieren
+        try:
+            user_id_int = int(user_id)
+        except (ValueError, TypeError):
+            app_logger.error(f"Ungültige User-ID: {user_id}")
+            return None
+            
         db_session = get_db_session()
         
         # Robuste Abfrage mit Error-Handling
         try:
-            user = db_session.query(User).filter(User.id == user_id).first()
+            user = db_session.query(User).filter(User.id == user_id_int).first()
             db_session.close()
             return user
         except Exception as db_error:
             # Schema-Problem - versuche manuelle Abfrage
-            app_logger.warning(f"Schema-Problem beim User-Load für ID {user_id}: {str(db_error)}")
+            app_logger.warning(f"Schema-Problem beim User-Load für ID {user_id_int}: {str(db_error)}")
             
             # Manuelle Abfrage nur mit Basis-Feldern
             try:
                 result = db_session.execute(
                     text("SELECT id, email, password_hash, name, role, active FROM users WHERE id = :user_id"),
-                    {"user_id": user_id}
+                    {"user_id": user_id_int}
                 ).fetchone()
                 
                 if result:
                     # Manuell User-Objekt erstellen
                     user = User()
                     user.id = result[0]
-                    user.email = result[1] if len(result) > 1 else f"user_{user_id}@system.local"
+                    user.email = result[1] if len(result) > 1 else f"user_{user_id_int}@system.local"
                     user.password_hash = result[2] if len(result) > 2 else ""
-                    user.name = result[3] if len(result) > 3 else f"User {user_id}"
+                    user.name = result[3] if len(result) > 3 else f"User {user_id_int}"
                     user.role = result[4] if len(result) > 4 else "user"
                     user.active = result[5] if len(result) > 5 else True
                     
@@ -4457,9 +4464,12 @@ def get_notifications():
     try:
         db_session = get_db_session()
         
+        # Sicherstellen, dass current_user.id als Integer behandelt wird
+        user_id = int(current_user.id)
+        
         # Benachrichtigungen für den aktuellen Benutzer laden
         notifications = db_session.query(Notification).filter(
-            Notification.user_id == current_user.id
+            Notification.user_id == user_id
         ).order_by(Notification.created_at.desc()).limit(50).all()
         
         notifications_data = [notification.to_dict() for notification in notifications]
@@ -4485,9 +4495,12 @@ def mark_notification_read(notification_id):
     try:
         db_session = get_db_session()
         
+        # Sicherstellen, dass current_user.id als Integer behandelt wird
+        user_id = int(current_user.id)
+        
         notification = db_session.query(Notification).filter(
             Notification.id == notification_id,
-            Notification.user_id == current_user.id
+            Notification.user_id == user_id
         ).first()
         
         if not notification:
@@ -4520,9 +4533,12 @@ def mark_all_notifications_read():
     try:
         db_session = get_db_session()
         
+        # Sicherstellen, dass current_user.id als Integer behandelt wird
+        user_id = int(current_user.id)
+        
         # Alle ungelesenen Benachrichtigungen des Benutzers finden und als gelesen markieren
         updated_count = db_session.query(Notification).filter(
-            Notification.user_id == current_user.id,
+            Notification.user_id == user_id,
             Notification.read == False
         ).update({"read": True})