In previous release you could specify a custom metrics reporter like so:
Properties config = new Properties();
From 0.11.0.0 onwards this is no longer possible, as you have to specify consumer.custom-key-for-metric-reporter or producer.custom-key-for-metric-reporter otherwise it's stripped out of the configuration.
So, if you wish to use a metrics reporter and to collect producer and consumer metrics, as well as kafka-streams metrics, that you would need to specify 3 distinct configs:
This appears to be a regression.