Thanks for the PR @rondagostino I wonder how we missed that in the initial implementation. Turns out `OAuthBearerSaslClient#retrieveCustomExtensions()` will return null if the `SaslExtensionsCallback` is not populated, meaning the initial changes in [KAFKA-7169](https://issues.apache.org/jira/browse/KAFKA-7169) were not backwards-compatible due to this bug.
I'm just not sure if we should even check for `null`. I think the approach of never returning `null` extensions might be better via updating `SaslExtensionsCallback` [ Full content available at: https://github.com/apache/kafka/pull/5552 ] This message was relayed via gitbox.apache.org for [email protected]
