fix: Chat failed notifications are not sent when the provider returns an error status (#32198)

Notification targets subscribed to Chat failed stayed silent when the provider answered a chat with an error status, such as a 500, or could not be reached at all. Those failures show up as an error in the chat, but only a few uncommon failures were announced to the targets. Now these failures notify Chat failed targets too, with the error text and a link to the chat.

Fixes #32003

backend/open_webui/main.py

@@ -253,6 +253,7 @@ from open_webui.utils.middleware import (
     build_chat_response_context,
     process_chat_payload,
     process_chat_response,
+    publish_chat_failed_event,
 )
 from open_webui.utils.misc import get_response_error_detail, merge_model_params
 from open_webui.utils.model_ids import strip_provider_model_prefix
@@ -1707,6 +1708,11 @@ async def chat_completion(
                                 )
                         except Exception:
                             log.exception('Failed to emit chat error')
+
+                        try:
+                            await publish_chat_failed_event(request, user, metadata, str(error_detail))
+                        except Exception:
+                            log.exception('Failed to publish chat failed event')
         finally:
             # Clean up MCP clients.  Each client is isolated so one
             # failure doesn't skip the rest.

backend/open_webui/utils/middleware.py

@@ -237,6 +237,30 @@ async def publish_chat_finished_event(
         await event_emitter({'type': 'chat:list', 'data': {'chat_id': chat_id, 'folder_id': folder_id}})
 
 
+async def publish_chat_failed_event(request: Request, user: UserModel, metadata: dict, error: str):
+    chat_id = metadata.get('chat_id')
+    if getattr(request.state, 'internal', False) is True or not is_saved_chat_id(chat_id):
+        return
+
+    webui_url = await Config.get('webui.url')
+    await publish_event(
+        request,
+        EVENTS.CHAT_FAILED,
+        actor=user,
+        subject_id=chat_id,
+        subject_type='chat',
+        data={
+            'user_id': user.id,
+            'chat_id': chat_id,
+            'message_id': metadata.get('message_id'),
+            'model_id': metadata.get('model_id'),
+            'url': f'{webui_url}/c/{chat_id}' if webui_url else f'/c/{chat_id}',
+            'message': error,
+        },
+        message='Chat failed',
+    )
+
+
 # We believe in one maker of all models, seen and unseen,
 # and in the reasoning which proceeds from the architect.
 # We look for the resurrection of dead processes and the
@@ -4361,25 +4385,7 @@ async def non_streaming_chat_response_handler(response, ctx):
             response = build_response_object(response, merge_events_into_response(response_data, events))
         except Exception as e:
             log.debug('Error occurred while processing request: %s', e)
-            chat_id = metadata.get('chat_id')
-            if getattr(request.state, 'internal', False) is not True and chat_id and is_saved_chat_id(chat_id):
-                webui_url = await Config.get('webui.url')
-                await publish_event(
-                    request,
-                    EVENTS.CHAT_FAILED,
-                    actor=user,
-                    subject_id=chat_id,
-                    subject_type='chat',
-                    data={
-                        'user_id': user.id,
-                        'chat_id': chat_id,
-                        'message_id': metadata.get('message_id'),
-                        'model_id': metadata.get('model_id'),
-                        'url': f'{webui_url}/c/{chat_id}' if webui_url else f'/c/{chat_id}',
-                        'message': str(e),
-                    },
-                    message='Chat failed',
-                )
+            await publish_chat_failed_event(request, user, metadata, str(e))
             pass
 
         return response