From c6ddf6d8988af611cfe778a397d08d7aa053a0bc Mon Sep 17 00:00:00 2001
From: "sentry[bot]" <39604003+sentry[bot]@users.noreply.github.com>
Date: Fri, 10 Jul 2026 22:38:14 +0000
Subject: [PATCH] fix(detectors): Safely access queryObj for cron monitors

---
 .../app/views/detectors/components/detectorLink.tsx   |  6 +++++-
 static/app/views/detectors/list/cron.tsx              | 11 ++++++-----
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/static/app/views/detectors/components/detectorLink.tsx b/static/app/views/detectors/components/detectorLink.tsx
index 6b0cb8e091bc..d21322284a27 100644
--- a/static/app/views/detectors/components/detectorLink.tsx
+++ b/static/app/views/detectors/components/detectorLink.tsx
@@ -214,7 +214,11 @@ function UptimeDetectorDetails({detector}: {detector: UptimeDetector}) {
 }
 
 function CronDetectorDetails({detector}: {detector: CronDetector}) {
-  const config = detector.dataSources[0].queryObj.config;
+  const config = detector.dataSources[0]?.queryObj?.config;
+
+  if (!config) {
+    return null;
+  }
 
   return <DetailItem>{scheduleAsText(config)}</DetailItem>;
 }
diff --git a/static/app/views/detectors/list/cron.tsx b/static/app/views/detectors/list/cron.tsx
index 8c3be5297043..ff6b3ec04532 100644
--- a/static/app/views/detectors/list/cron.tsx
+++ b/static/app/views/detectors/list/cron.tsx
@@ -52,15 +52,16 @@ import {selectCheckInData} from 'sentry/views/insights/crons/utils/selectCheckIn
 import {useMonitorStats} from 'sentry/views/insights/crons/utils/useMonitorStats';
 
 function VisualizationCell({detector}: {detector: CronDetector}) {
-  const cronId = detector.dataSources[0].queryObj.id;
-  const cronEnvironments = detector.dataSources[0].queryObj.environments;
+  const queryObj = detector.dataSources[0]?.queryObj;
+  const cronId = queryObj?.id;
+  const cronEnvironments = queryObj?.environments;
 
   const elementRef = useRef<HTMLDivElement>(null);
   const {width: containerWidth} = useDimensions({elementRef});
   const timelineWidth = useDebouncedValue(containerWidth, 1000);
   const timeWindowConfig = useTimeWindowConfig({timelineWidth});
   const {data: monitorStats, isPending} = useMonitorStats({
-    monitors: [detector.dataSources[0].queryObj.id],
+    monitors: cronId ? [cronId] : [],
     timeWindowConfig,
   });
 
@@ -72,7 +73,7 @@ function VisualizationCell({detector}: {detector: CronDetector}) {
       height="100%"
     >
       <Stack gap="sm" width="100%" ref={elementRef}>
-        {cronEnvironments.map(environment => {
+        {cronEnvironments?.map(environment => {
           if (isPending) {
             return <CheckInPlaceholder key={environment.name} />;
           }
@@ -108,7 +109,7 @@ const ADDITIONAL_COLUMNS: MonitorListAdditionalColumn[] = [
       return (
         <SimpleTable.RowCell data-column-name="environment-label" alignSelf="start">
           <Stack gap="sm" width="100%">
-            {detector.dataSources[0].queryObj.environments.map(environment => {
+            {detector.dataSources[0]?.queryObj?.environments.map(environment => {
               return (
                 <Text density="compressed" key={environment.name}>
                   <MonitorEnvironmentLabel