Exceptions thrown when calling Sentry.captureException in Flutter app

[GowthamanRavichandran3]

Platform

Flutter Mobile Android, Flutter Mobile iOS

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Doctor

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! Doctor found issues in 2 categories.

Version

9.0.0

Steps to Reproduce

I am using the following code in my Flutter app to capture exceptions and send them to Sentry:
await Sentry.captureException(exception, stackTrace: stackTrace);

However, when this line executes, I encounter the following exceptions in my app:

1. TimeoutException after 0:00:03.000000: Future not completed
2. 429: Too Many Requests
3. HandshakeException: Connection terminated during handshake

What I Tried

1. Using try-catch block:

try {
  await Sentry.captureException(
    exception,
    stackTrace: stackTrace,
  );
} catch (e, sentryErrorStack) {
  debugPrint('Failed to report to Sentry: $e');
  debugPrint('Sentry error stack: $sentryErrorStack');
}

But the exceptions are not caught in the catch block.

2. Using catchError:

await Sentry.captureException(error, stackTrace: trace).catchError((e, st) {
  return const SentryId.empty();
});

Even with this, the exceptions are still thrown and logged in Sentry.

Expected Result

I want to prevent these network-related exceptions (TimeoutException, 429 Too Many Requests, HandshakeException) from being logged in Sentry or at least handle them gracefully without crashing the app.

Actual Result

The exceptions are thrown and logged in Sentry despite using try-catch and catchError.

Are you willing to submit a PR?

None

[linear]

DART-263

[buenaflor]

hey do you mean that Sentry causes these exceptions and logs them?

if yes can you send a link to one of these events to my mail at giancarlo.buenaflor@sentry.io

[GowthamanRavichandran3]

hey do you mean that Sentry causes these exceptions and logs them?

if yes can you send a link to one of these events to my mail at giancarlo.buenaflor@sentry.io

Yes, these exceptions occur when I call Sentry.captureException() in my Flutter app. It seem to be related to the network call Sentry makes to send the event (e.g., TimeoutException, 429 Too Many Requests, HandshakeException).

I’m using a self-hosted Sentry instance, so the event links are internal and not publicly accessible.

[buenaflor]

do you have stacktraces you could share?