Refactor DatabaseFactory to lazily initialize the lock and improve file record handling in BatchService

Author: Pavan-Microsoft

src/backend/common/database/database_factory.py

@@ -9,15 +9,21 @@
 
 class DatabaseFactory:
     _instance: Optional[DatabaseBase] = None
-    _lock: asyncio.Lock = asyncio.Lock()
+    _lock: Optional[asyncio.Lock] = None
     _logger = AppLogger("DatabaseFactory")
 
+    @staticmethod
+    def _get_lock() -> asyncio.Lock:
+        if DatabaseFactory._lock is None:
+            DatabaseFactory._lock = asyncio.Lock()
+        return DatabaseFactory._lock
+
     @staticmethod
     async def get_database():
         if DatabaseFactory._instance is not None:
             return DatabaseFactory._instance
 
-        async with DatabaseFactory._lock:
+        async with DatabaseFactory._get_lock():
             # Double-check after acquiring the lock
             if DatabaseFactory._instance is not None:
                 return DatabaseFactory._instance

src/backend/common/services/batch_service.py

@@ -288,7 +288,8 @@ async def upload_file_to_batch(self, batch_id: str, user_id: str, file: UploadFi
 
             # Create file entry
             file_record_obj = await self.database.add_file(batch_id, file_id, file.filename, blob_path)
-            file_record = file_record_obj.dict() if hasattr(file_record_obj, 'dict') else file_record_obj
+            file_record_dict = getattr(file_record_obj, "dict", None)
+            file_record = file_record_dict() if callable(file_record_dict) else file_record_obj
 
             await self.database.add_file_log(
                 UUID(file_id),