I am using refreshable and cookie options for session handling.

OneOff option works as expected but I am unable to get the refreshable option to work.

Setting session max-age to less than refresh max-age results in session timing (as expected).

If using directive requiredSession and session expires I get the following exception thrown (appears to be thrown by processing of directive:

LB, 13:15:43.135UTC ERROR[TheSystem-akka.actor.default-dispatcher-9] ActorSystemImpl - Error during processing of request: 'java.lang.NullPointerException (No error message supplied)'. Completing with 500 Internal Server Error response. To change default exception handling behavior, provide a custom ExceptionHandler. 
java.lang.NullPointerException: null
	at scala.concurrent.impl.Promise$Transformation.<init>(Promise.scala:382)
	at scala.concurrent.impl.Promise$DefaultPromise.flatMap(Promise.scala:140)
	at com.softwaremill.session.RefreshTokenManager.sessionFromValue(SessionManager.scala:180)
	at com.softwaremill.session.RefreshTokenManager.sessionFromValue$(SessionManager.scala:177)

I see the same behavior if I use directive optionalSession.

My understanding is that the refreshing of token (if using cookie based continuity) is done behind the scenes with no required interaction - is this correct?

Am I missing something? I assume I must be doing something wrong as I would imagine this issue would have been reported.