From 223ec57fe4d9039836b6259458cd207d9994a262 Mon Sep 17 00:00:00 2001
From: Willem Jiang <willem.jiang@gmail.com>
Date: Fri, 28 Nov 2025 08:35:42 +0800
Subject: [PATCH] fix: the frontend error when cancle the research plan (#719)

Co-authored-by: Willem Jiang <143703838+willem-bd@users.noreply.github.com>
---
 src/server/app.py | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/server/app.py b/src/server/app.py
index 12e7eff..110d5a3 100644
--- a/src/server/app.py
+++ b/src/server/app.py
@@ -487,6 +487,11 @@ async def _stream_graph_events(
                 yield event
         
         logger.debug(f"[{safe_thread_id}] Graph event stream completed. Total events: {event_count}")
+    except asyncio.CancelledError:
+        # User cancelled/interrupted the stream - this is normal, not an error
+        logger.info(f"[{safe_thread_id}] Graph event stream cancelled by user after {event_count} events")
+        # Re-raise to signal cancellation properly without yielding an error event
+        raise
     except Exception as e:
         logger.exception(f"[{safe_thread_id}] Error during graph execution")
         yield _make_event(