Skip "Handled" error

[Syed-RI]

Trying to prevent Sentry sending errors that are handled in a try catch

try
{
..... throws exception
}
catch (Exception ex)
{
 ILogger.LogException(ex, "MyHandledException")
}

will something like below work?

// Add this to the SDK initialization callback
options.SetBeforeSend((sentryEvent, hint) =>
{

   if (HasTerminalException(sentryEvent.Exception, sentryEvent.SentryExceptions))
   {
       System.Diagnostics.Trace.WriteLine(
           $"[TRACE]: Sentry event is being sent: {sentryEvent.EventId} - {sentryEvent.Message}");

       return sentryEvent;
   }

   System.Diagnostics.Trace.WriteLine(
       $"[TRACE]: Sentry event is being dropped: {sentryEvent.EventId} - {sentryEvent.Message}");

   return null;

   bool HasTerminalException(Exception? ex, IEnumerable<SentryException>? ses)
   {
       // The exception is considered terminal if it is marked unhandled,
       // UNLESS it comes from the UnobservedTaskExceptionIntegration

       if (ex?.Data[Mechanism.HandledKey] is false)
       {
           return ex.Data[Mechanism.MechanismKey] as string != "UnobservedTaskException";
       }

       return ses?.Any(e => e.Mechanism is { Handled: false } mechanism &&
                            mechanism.Type != "UnobservedTaskException") ?? false;
   }
});

Or there is a better way?

[jamescrosswell]

@Syed-RI

TLDR;

From what I can tell, you never want Exceptions that get logged via ILogger to be turned into events that get to Sentry. The easiest way to do that is just to set options.MinimumEventLevel = LogLevel.None when initialising Sentry... if you do that, nothing you log via the ILogger interface will be captured as an Event in Sentry.

Long explanation

Mechanism.Handled is generally only set to false for exceptions that you don't catch and which the Sentry SDK catches automatically (e.g. via the AppDomainUnhandledExceptionIntegration).

Exceptions that are captured from your own code, via SentrySdk.CaptureException or ILogger (where the log level is higher than SentryLoggingOption.MinimumEventLevel) will almost always have handled set to true.

I think you could check for unhandled exceptions with something like:

        sentryEvent.SentryExceptions?.Any(e => e.Mechanism is { Handled: false }) ?? false;

However filtering all handled exceptions would prevent something like the following from being captured:

  try {
    throw new Exception();
  }
  catch (Exception e) {
    SentrySdk.CaptureException(e);
  }

I don't think you want to do that.

[Syed-RI]

I settle with the first option. Just to clarify, setting options.MinimumEventLevel = LogLevel.None will still catch and report crashes in the Sentry portal?

[jamescrosswell]

setting options.MinimumEventLevel = LogLevel.None will still catch and report crashes in the Sentry portal?

Yes any exceptions captured either by the Sentry SDK (e.g. unhandled exceptions) or explicitly using the Sentry API (e.g. SentrySdk.CaptureException) will still be captured and sent to Sentry. It just means that no exceptions/events will be generated for logs (regardless of the log level).