fix empty null value db insert

backend/src/utilities/database.py

@@ -91,10 +91,15 @@ def _derive_flow_id(payload: Dict[str, Any]) -> Optional[str]:
 
 
 def _attach_derived_fields(payload: Dict[str, Any]) -> None:
-    if payload.get("flow_id") in (None, ""):
-        flow_id = _derive_flow_id(payload)
-        if flow_id is not None:
+    flow_id = _derive_flow_id(payload)
+    if flow_id is not None:
+        current_flow_id = payload.get("flow_id")
+        if current_flow_id in (None, ""):
             payload["flow_id"] = flow_id
+        else:
+            session_id = payload.get("capture_session_id")
+            if session_id not in (None, "") and current_flow_id == flow_id.split(":", 1)[1]:
+                payload["flow_id"] = flow_id
 
     if payload.get("raw_present") is None:
         payload["raw_present"] = payload.get("raw") is not None
@@ -172,6 +177,9 @@ class DatabasePool:
         if self._pool is None:
             await self.init_pool()
 
+        _normalize_json_fields(pkt_info)
+        _attach_derived_fields(pkt_info)
+
         dpi_metadata = pkt_info.get("dpi_metadata")
         telemetry_metadata = pkt_info.get("telemetry_metadata")