Flutter plugin reporting NSURLErrorCancelled when using certificate pinning on iOS

[jcornelius]

When using the Dart ssl_pinning_plugin check() method to validate certificates for a DNS, it creates a connection to retrieve the certificate info and then terminates the connection which results in the Dynatrace Flutter plugin reporting an error of -999 NSURLErrorCancelled on iOS. 

 

I cannot find a way to exclude that from being reported as an error and as such is causing all the user sessions for iOS to have high error rates and a poor Apdex rating.  We are able to exclude common response codes like 4xx or 5xx from being reported in Dynatrace but I do not see a way to exclude this particular error.  Is there something that can be configured either in Dynatrace or in the Dart code to exclude this?

[Patrick_H · Accepted solution]

On Dynatrace cluster side everything that is a HTTP code can be excluded from treating it as error, but this does not apply to other error responses, so anything that is not a 3-digit number in the HTTP response codes range is treated as an error (negative numbers, strings,...) and currently cannot be ignored.
FYI @thomas_billi  do we have an improvement for that situation planned?

[thomas_billi]

It's definitely a limitation that we are aware of. We do not yet know how we will address it.

[paul_kapeller]

more customizable exclusion rules are planned with OpenPipeline and the new Platform once we ingest RUM data via OpenPipeline.

[eddbarrientos19]

Good evening

Is there any update on how to exclude a "-999NSURLErrorCancelled" error as it is not an HTTP code.

I have a client who is presenting the same error and they are looking to exclude it