Hi there, I am having problems aggregating metrics for our monitoring system, because some JMX beans use dots in its names (e.g. kafka.server:type=BrokerTopicMetrics,name=MessagesInPerSec, "topic" just uses the plain topic name as is).
Other JMX beans replace dots by underscores, like the one added in the PR. What is the problem when using dots in the topic name there? At least in our case, everything seems to work fine, even though our topics do contain dots. However, the current behavior is different between these metrics which makes combining the metrics hard. Please also see https://github.com/apache/kafka/pull/4362#discussion_r203949516. Thanks, Mathias
