fix(tracing): Bound TTID/TTFD to prevent inflated transactions

CHANGELOG.md

@@ -8,6 +8,10 @@
 
 ## Unreleased
 
+### Fixes
+
+- Bound TTID/TTFD to prevent inflated transactions ([#6210](https://github.com/getsentry/sentry-react-native/pull/6210))
+
 ### Features
 
 - Expose `pauseAppHangTracking` and `resumeAppHangTracking` APIs on iOS ([#6192](https://github.com/getsentry/sentry-react-native/pull/6192))

packages/core/src/js/tracing/integrations/timeToDisplayIntegration.ts

@@ -57,30 +57,41 @@
       });
       const ttfdSpan = await addTimeToFullDisplay({ event, rootSpanId, transactionStartTimestampSeconds, ttidSpan });
 
-      if (ttidSpan?.start_timestamp && ttidSpan?.timestamp) {
+      const ttidDurationMs =
+        ttidSpan?.start_timestamp && ttidSpan?.timestamp
+          ? (ttidSpan.timestamp - ttidSpan.start_timestamp) * 1000
+          : undefined;
+      const ttidDeadlineExceeded = ttidDurationMs !== undefined && isDeadlineExceeded(ttidDurationMs);
+
+      if (ttidDurationMs !== undefined && !ttidDeadlineExceeded) {
         event.measurements['time_to_initial_display'] = {
-          value: (ttidSpan.timestamp - ttidSpan.start_timestamp) * 1000,
+          value: ttidDurationMs,
           unit: 'millisecond',
         };
       }
 
-      if (ttfdSpan?.start_timestamp && ttfdSpan?.timestamp) {
-        const durationMs = (ttfdSpan.timestamp - ttfdSpan.start_timestamp) * 1000;
-        if (isDeadlineExceeded(durationMs)) {
+      const ttfdDurationMs =
+        ttfdSpan?.start_timestamp && ttfdSpan?.timestamp
+          ? (ttfdSpan.timestamp - ttfdSpan.start_timestamp) * 1000
+          : undefined;
+      const ttfdDeadlineExceeded = ttfdDurationMs !== undefined && isDeadlineExceeded(ttfdDurationMs);
+
+      if (ttfdDurationMs !== undefined) {
+        if (ttfdDeadlineExceeded) {
           if (event.measurements['time_to_initial_display']) {
             event.measurements['time_to_full_display'] = event.measurements['time_to_initial_display'];
           }
         } else {
           event.measurements['time_to_full_display'] = {
-            value: durationMs,
+            value: ttfdDurationMs,
             unit: 'millisecond',
           };
         }
       }
 
       const newTransactionEndTimestampSeconds = Math.max(
-        ttidSpan?.timestamp ?? -1,
-        ttfdSpan?.timestamp ?? -1,
+        (!ttidDeadlineExceeded && ttidSpan?.timestamp) ? ttidSpan.timestamp : -1,
+        (!ttfdDeadlineExceeded && ttfdSpan?.timestamp) ? ttfdSpan.timestamp : -1,
         event.timestamp ?? -1,
       );
       if (newTransactionEndTimestampSeconds !== -1) {
@@ -126,14 +137,18 @@
     });
   }
 
+  const manualDurationMs = (ttidEndTimestampSeconds - transactionStartTimestampSeconds) * 1000;
+  const manualStatus = isDeadlineExceeded(manualDurationMs) ? 'deadline_exceeded' : 'ok';
+
   if (ttidSpan?.status && ttidSpan.status !== 'ok') {
-    ttidSpan.status = 'ok';
+    ttidSpan.status = manualStatus;
     ttidSpan.timestamp = ttidEndTimestampSeconds;
     debug.log(`[${INTEGRATION_NAME}] Updated existing ttid span.`, ttidSpan);
     return ttidSpan;
   }
 
   ttidSpan = createSpanJSON({
+    status: manualStatus,
     op: UI_LOAD_INITIAL_DISPLAY,
     description: 'Time To Initial Display',
     start_timestamp: transactionStartTimestampSeconds,
@@ -180,7 +195,9 @@
   const viewNames = event.contexts?.app?.view_names;
   const screenName = Array.isArray(viewNames) ? viewNames[0] : viewNames;
 
+  const durationMs = (ttidTimestampSeconds - transactionStartTimestampSeconds) * 1000;
   const ttidSpan = createSpanJSON({
+    status: isDeadlineExceeded(durationMs) ? 'deadline_exceeded' : 'ok',
     op: UI_LOAD_INITIAL_DISPLAY,
     description: screenName ? `${screenName} initial display` : 'Time To Initial Display',
     start_timestamp: transactionStartTimestampSeconds,

packages/core/test/tracing/reactnavigation.ttid.test.tsx

@@ -433,8 +433,45 @@
       );
     });
 
+    test('should mark ttid as deadline_exceeded and not extend transaction when ttid exceeds 30s', () => {
+      jest.runOnlyPendingTimers(); // Flush app start transaction
+
+      mockedNavigation.navigateToNewScreen();
+      const activeSpanId = spanToJSON(getActiveSpan()).span_id;
+      const transactionStartTimestamp = spanToJSON(getActiveSpan()).start_timestamp;
+
+      // Simulate a stale TTID 60 seconds after the transaction start
+      mockRecordedTimeToDisplay({
+        ttidNavigation: {
+          [activeSpanId]: transactionStartTimestamp + 60,
+        },
+      });
+      jest.runOnlyPendingTimers(); // Flush ttid transaction
+
+      const transaction = getLastTransaction(transportSendMock);
+      expect(transaction).toEqual(
+        expect.objectContaining<TransactionEvent>({
+          type: 'transaction',
+          spans: expect.arrayContaining([
+            expect.objectContaining<Partial<SpanJSON>>({
+              op: 'ui.load.initial_display',
+              status: 'deadline_exceeded',
+            }),
+          ]),
+        }),
+      );
+      expect(transaction.measurements).toBeOneOf([
+        undefined,
+        expect.not.objectContaining<Required<TransactionEvent>['measurements']>({
+          time_to_initial_display: expect.any(Object),
+        }),
+      ]);
+      // Transaction timestamp should NOT be extended to the stale TTID
+      expect(transaction.timestamp - transaction.start_timestamp).toBeLessThan(30);
+    });
+
     test('should not sample empty back navigation transactions with navigation processing', () => {
       jest.runOnlyPendingTimers(); // Flush app start transaction
 
       mockedNavigation.navigateToNewScreen();
       mockAutomaticTimeToDisplay();

packages/core/test/tracing/timetodisplay.test.tsx

@@ -292,6 +292,77 @@
     );
   });
 
+  test('deadline exceeded full display does not extend transaction timestamp', async () => {
+    let transactionStartTimestamp: number;
+
+    startSpanManual(
+      {
+        name: 'Root Manual Span',
+        startTime: secondAgoTimestampMs(),
+      },
+      (activeSpan: Span | undefined) => {
+        transactionStartTimestamp = spanToJSON(activeSpan).start_timestamp;
+        startTimeToInitialDisplaySpan();
+        startTimeToFullDisplaySpan();
+
+        render(<TimeToInitialDisplay record={true} />);
+        render(<TimeToFullDisplay record={true} />);
+
+        mockRecordedTimeToDisplay({
+          ttid: {
+            [spanToJSON(activeSpan).span_id]: nowInSeconds(),
+          },
+          ttfd: {
+            [spanToJSON(activeSpan).span_id]: nowInSeconds() + 60,
+          },
+        });
+
+        activeSpan?.end();
+      },
+    );
+
+    await jest.runOnlyPendingTimersAsync();
+    await client.flush();
+
+    const event = client.event!;
+    expect(event.timestamp! - transactionStartTimestamp!).toBeLessThan(30);
+  });
+
+  test('deadline exceeded manual initial display does not extend transaction timestamp', async () => {
+    let transactionStartTimestamp: number;
+
+    startSpanManual(
+      {
+        name: 'Root Manual Span',
+        startTime: secondAgoTimestampMs(),
+      },
+      (activeSpan: Span | undefined) => {
+        transactionStartTimestamp = spanToJSON(activeSpan).start_timestamp;
+        startTimeToInitialDisplaySpan();
+
+        render(<TimeToInitialDisplay record={true} />);
+
+        mockRecordedTimeToDisplay({
+          ttid: {
+            [spanToJSON(activeSpan).span_id]: nowInSeconds() + 60,
+          },
+        });
+
+        activeSpan?.end();
+      },
+    );
+
+    await jest.runOnlyPendingTimersAsync();
+    await client.flush();
+
+    const event = client.event!;
+    expectNoInitialDisplayMeasurementOnSpan(event);
+    expect(event.timestamp! - transactionStartTimestamp!).toBeLessThan(30);
+
+    const ttidSpan = event.spans!.find(s => s.op === 'ui.load.initial_display');
+    expect(ttidSpan?.status).toBe('deadline_exceeded');
+  });
+
   test('full display which ended before initial display is extended to initial display end', async () => {
     const fullDisplayEndTimestampMs = secondInFutureTimestampMs();
     const initialDisplayEndTimestampMs = secondInFutureTimestampMs() + 500;