Fix (beta): retry celery ping and report warning on no response (#13012)

src-ui/src/app/components/common/system-status-dialog/system-status-dialog.component.html

@@ -131,7 +131,9 @@
                   @if (status.tasks.celery_status === 'OK') {
                     <i-bs name="check-circle-fill" class="text-primary ms-2 lh-1"></i-bs>
                   } @else {
-                    <i-bs name="exclamation-triangle-fill" class="text-danger ms-2 lh-1"></i-bs>
+                    <i-bs name="exclamation-triangle-fill" class="ms-2 lh-1"
+                    [class.text-danger]="status.tasks.celery_status === SystemStatusItemStatus.ERROR"
+                    [class.text-warning]="status.tasks.celery_status === SystemStatusItemStatus.WARNING"></i-bs>
                   }
                 </button>
                 <ng-template #celeryStatus>

src/documents/tests/test_api_status.py

@@ -216,6 +216,77 @@ class TestSystemStatus(APITestCase):
         self.assertEqual(response.status_code, status.HTTP_200_OK)
         self.assertEqual(response.data["tasks"]["celery_status"], "OK")
 
+    @mock.patch("celery.app.control.Inspect.ping")
+    def test_system_status_celery_ping_none(self, mock_ping) -> None:
+        """
+        GIVEN:
+            - Celery ping returns no worker responses
+        WHEN:
+            - The user requests the system status
+        THEN:
+            - The response contains a warning celery status
+        """
+        mock_ping.return_value = None
+        self.client.force_login(self.user)
+        response = self.client.get(self.ENDPOINT)
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        self.assertEqual(response.data["tasks"]["celery_status"], "WARNING")
+        self.assertEqual(
+            response.data["tasks"]["celery_error"],
+            "No celery workers responded to ping. This may be temporary.",
+        )
+
+    @mock.patch("celery.app.control.Inspect.ping")
+    def test_system_status_celery_ping_unexpected_responses(self, mock_ping) -> None:
+        """
+        GIVEN:
+            - Celery ping returns an unexpected worker response
+        WHEN:
+            - The user requests the system status
+        THEN:
+            - The response contains a warning celery status
+        """
+        self.client.force_login(self.user)
+        for ping_response in (
+            {"hostname": {"ok": "not-pong"}},
+            {"hostname": {}},
+            {"hostname": "pong"},
+        ):
+            with self.subTest(ping_response=ping_response):
+                mock_ping.return_value = ping_response
+                response = self.client.get(self.ENDPOINT)
+                self.assertEqual(response.status_code, status.HTTP_200_OK)
+                self.assertEqual(response.data["tasks"]["celery_status"], "WARNING")
+                self.assertEqual(response.data["tasks"]["celery_url"], "hostname")
+                self.assertEqual(
+                    response.data["tasks"]["celery_error"],
+                    "Celery worker responded unexpectedly.",
+                )
+
+    @mock.patch("documents.views.sleep")
+    @mock.patch("celery.app.control.Inspect.ping")
+    def test_system_status_celery_ping_retry_success(
+        self,
+        mock_ping,
+        mock_sleep,
+    ) -> None:
+        """
+        GIVEN:
+            - Celery ping fails once but succeeds on retry
+        WHEN:
+            - The user requests the system status
+        THEN:
+            - The response contains an OK celery status
+        """
+        mock_ping.side_effect = [None, {"hostname": {"ok": "pong"}}]
+        self.client.force_login(self.user)
+        response = self.client.get(self.ENDPOINT)
+        self.assertEqual(response.status_code, status.HTTP_200_OK)
+        self.assertEqual(response.data["tasks"]["celery_status"], "OK")
+        self.assertIsNone(response.data["tasks"]["celery_error"])
+        self.assertEqual(mock_ping.call_count, 2)
+        mock_sleep.assert_called_once_with(0.25)
+
     @mock.patch("documents.search.get_backend")
     def test_system_status_index_ok(self, mock_get_backend) -> None:
         """

src/documents/views.py

@@ -12,6 +12,7 @@ from datetime import timedelta
 from http import HTTPStatus
 from pathlib import Path
 from time import mktime
+from time import sleep
 from typing import TYPE_CHECKING
 from typing import Any
 from typing import Literal
@@ -4990,11 +4991,29 @@ class SystemStatusView(PassUserMixin):
         celery_error = None
         celery_url = None
         try:
-            celery_ping = celery_app.control.inspect().ping()
-            celery_url = next(iter(celery_ping.keys()))
-            first_worker_ping = celery_ping[celery_url]
-            if first_worker_ping["ok"] == "pong":
-                celery_active = "OK"
+            celery_ping = None
+            for ping_attempt in range(3):
+                celery_ping = celery_app.control.inspect().ping()
+                if celery_ping:
+                    break
+                if ping_attempt < 2:
+                    sleep(0.25)
+
+            if not celery_ping:
+                celery_active = "WARNING"
+                celery_error = (
+                    "No celery workers responded to ping. This may be temporary."
+                )
+            else:
+                celery_url, first_worker_ping = next(iter(celery_ping.items()))
+                if (
+                    isinstance(first_worker_ping, dict)
+                    and first_worker_ping.get("ok") == "pong"
+                ):
+                    celery_active = "OK"
+                else:
+                    celery_active = "WARNING"
+                    celery_error = "Celery worker responded unexpectedly."
         except Exception as e:
             celery_active = "ERROR"
             logger.exception(