How to not send network errors to Sentry?

[GP4cK]

I have a flutter mobile app where users may frequently be offline or have a weak network connection. As it's an expected behaviour, I would like to not send these errors to Sentry.

Here is how I configured Sentry:

await SentryFlutter.init(
  (options) {
    options
      ..beforeSend = (event, hint) {
        final throwable = event.throwable;
        if (throwable is ClientException) return null;
        if (throwable case final ServerException e when e.originalException is ClientException) return null;
        return event;
      }
      //...
  },
)

However, I still see errors such as:

ClientException: Cronet exception: m1.mh: Exception in CronetUrlRequest: net::ERR_CONNECTION_ABORTED, ErrorCode=11, InternalErrorCode=-103, Retryable=false,

When prompting Seer, it tells me

SentryHttpClient captures and sends ClientException.

Because HttpClientBinding.instance is a SentryHttpClient, it automatically catches the ClientException thrown by the underlying HTTP client. SentryHttpClient is designed to capture these HTTP-related errors and send them to Sentry immediately, potentially bypassing the global beforeSend filter configured in SentryFlutter.init() for manually captured exceptions.

Is this true? What's the best way to ignore network errors?

[buenaflor]

hey, are you able to share a link to the Sentry event with me at [email protected]

[GP4cK]

I sent the email to [email protected]. Thanks.

[buenaflor]

Thanks.

Using beforeSend here is the correct way.

bypassing the global beforeSend filter configured in SentryFlutter.init() for manually captured exceptions.

not true, all our events triggered in the Dart/Flutter layer go through the same pipeline and invoke beforeSend

[buenaflor]

At first glance of your events I don't see anything suspicious - your beforeSend implementation also looks correct.

I took a look at your newest release and it seems this error is not reported in those. Perhaps those errors are still coming in because some users are on older versions of your app still?

[GP4cK]

I took another look and you're right, it seems to be working as intended. I'm still getting events in the latest version but it's because they were wrongly batched together or the exception wasn't matching my filter.

Ex:

ServerException: ServerException(originalException: NSErrorClientException: The Internet connection appears to be offline.

Thank you so much!