Overridden version of xitrum.hazelcast.Session store to limit a user to a single session

Session.scala

package test.hazelcast

import com.hazelcast.core.IMap
import xitrum.hazelcast.{Hz, Session ⇒ HazelcastSession}

/** Overridden version of xitrum.hazelcast.Session store to limit a user to a
  * single session.
  */
class Session extends HazelcastSession {
  private[this] lazy val store = Hz.instance.getMap("xitrum/session").asInstanceOf[IMap[String, Map[String, Any]]]

  override def put(sessionId: String, immutableMap: Map[String, Any]): Unit = {
    store.set(sessionId, immutableMap)

    // Store current session id for the user
    immutableMap.get("username").map { username ⇒
      Option(store.get(username.asInstanceOf[String])).map { usermap ⇒
        usermap.get("username").map { sessionIdPrev ⇒
          if (sessionIdPrev.asInstanceOf[String] != sessionId) store.remove(usermap.getOrElse("username", ""))
        }
      }
      store.put(username.asInstanceOf[String], Map("username" → sessionId))
    }
  }

  override def remove(sessionId: String): Unit = {
    // First remove username -> sessionId mapping if available
    Option(store.get(sessionId)).map(_.get("username").map(username ⇒ store.remove(username.asInstanceOf[String])))
    store.remove(sessionId)
  }
}