Hi Committers, CURATOR-505 introduced circuit breaking behavior via CircuitBreakingConnectionStateListener and ConnectionStateListenerDecorator. Elastic has been using it with success but reports that the implementation can be improved. The existing implementation uses a new CircuitBreaker for each ConnectionStateListener set in a Curator client. It turns out that this is not ideal. Instead, a shared CircuitBreaker should be used per Curator client.
Unfortunately, the best way to do this is to remove the ConnectionStateListenerDecorator semantics and use a different mechanism. This Issue proposes to do this and remove ConnectionStateListenerDecorator. This is a breaking change but given the short amount of time it's been in Curator it's unlikely that it's been widely adopted. If the community considers a breaking change too harsh the older classes can be maintained for a while and marked as @Deprecated. Otherwise we can make the next release 4.3.0 (note: our semantic versioning has always been wrong - different issue) to denote a breaking change. I have a candidate PR here: https://github.com/apache/curator/pull/320 <https://github.com/apache/curator/pull/320> - the Jira issue is: https://issues.apache.org/jira/browse/CURATOR-533 <https://issues.apache.org/jira/browse/CURATOR-533> -Jordan
