put back try catch block for node expansion

ossdbtoolsservice/object_explorer/object_explorer_service.py

@@ -187,24 +187,27 @@ class ObjectExplorerService(object):
         if session is None:
             return
 
-        # Step 2: Start a task for expanding the node
-        key = params.node_path
-        if is_refresh:
-            task = session.refresh_tasks.get(key)
-        else:
-            task = session.expand_tasks.get(key)
+        try:
+            # Step 2: Start a task for expanding the node
+            key = params.node_path
+            if is_refresh:
+                task = session.refresh_tasks.get(key)
+            else:
+                task = session.expand_tasks.get(key)
 
-        if task is not None and task.is_alive():
-            return
+            if task is not None and task.is_alive():
+                return
 
-        new_task = threading.Thread(target=self._expand_node_thread, args=(is_refresh, request_context, params, session))
-        new_task.daemon = True
-        new_task.start()
+            new_task = threading.Thread(target=self._expand_node_thread, args=(is_refresh, request_context, params, session))
+            new_task.daemon = True
+            new_task.start()
 
-        if is_refresh:
-            session.refresh_tasks[key] = new_task
-        else:
-            session.expand_tasks[key] = new_task
+            if is_refresh:
+                session.refresh_tasks[key] = new_task
+            else:
+                session.expand_tasks[key] = new_task
+        except Exception as e:
+            self._expand_node_error(request_context, params, str(e))
 
     def _expand_node_thread(self, is_refresh: bool, request_context: RequestContext, params: ExpandParameters, session: ObjectExplorerSession, retry=False):
         try:
@@ -220,7 +223,7 @@ class ObjectExplorerService(object):
                 session.server.refresh()
                 self._expand_node_thread(is_refresh, request_context, params, session, True)
             else:
-                self._expand_node_error(request_context, params, str(e))
+                raise e
 
     def _expand_node_error(self, request_context: RequestContext, params: ExpandParameters, message: str):
         if self._service_provider.logger is not None: