Start implementing the bidirectional ping

app/Cron.scala

@@ -12,6 +12,10 @@ final class Cron(env: SystemEnv) {
   implicit val current = env.app
   implicit val timeout = Timeout(500 millis)
 
+  message(5 seconds) {
+    env.siteHub -> socket.Cleanup
+  }
+
   message(2 seconds) {
     env.reporting -> report.Update(env)
   }

app/memo/BooleanExpiryMemo.scala

@@ -16,6 +16,10 @@ abstract class BooleanExpiryMemo(timeout: Int) {
     cache.put(key, true)
   }
 
+  def putUnsafe(key: String): Unit = {
+    cache.put(key, true)
+  }
+
   def putAll(keys: Iterable[String]): IO[Unit] = io {
     keys map { cache.put(_, true) }
   }

app/site/Hub.scala

@@ -10,22 +10,34 @@ import play.api.libs.iteratee._
 final class Hub extends Actor {
 
   private var members = Map.empty[String, Member]
+  private val pinger = new Pinger
 
   def receive = {
 
+    case Ping(uid) ⇒ {
+      members get uid foreach { _.channel push Util.pong }
+    }
+
+    case Cleanup ⇒ members.keys filterNot pingers.get foreach { uid ⇒
+      self ! Quit(uid)
+    }
+
     case WithUsernames(op) ⇒ op(usernames).unsafePerformIO
 
     case Join(uid, username) ⇒ {
       val channel = new LilaEnumerator[JsValue](Nil)
       members = members + (uid -> Member(channel, username))
       sender ! Connected(channel)
+      pingers putUnsafe uid
     }
 
     case NbMembers    ⇒ notifyAll("n", JsNumber(members.size))
 
     case GetNbMembers ⇒ sender ! members.size
 
-    case Quit(uid)    ⇒ { members = members - uid }
+    case Quit(uid) ⇒ {
+      members = members - uid
+    }
   }
 
   private def notifyAll(t: String, data: JsValue) {

app/site/Socket.scala

@@ -11,7 +11,7 @@ import play.api.libs.concurrent._
 import scalaz.effects._
 
 import RichJs._
-import socket.Util
+import socket.{ Util, Ping }
 
 final class Socket(hub: ActorRef) {
 
@@ -26,9 +26,7 @@ final class Socket(hub: ActorRef) {
       case Connected(channel) ⇒
         val iteratee = Iteratee.foreach[JsValue] { e ⇒
           e str "t" match {
-            case Some("p") ⇒ {
-              channel push Util.pong
-            }
+            case Some("p") ⇒ hub ! Ping(uid)
             case _ ⇒
           }
           Unit

app/socket/PingMemo.scala

@@ -0,0 +1,5 @@
+package lila
+package socket
+
+// keys = uid
+final class PingMemo(timeout: Int) extends BooleanExpiryMemo(timeout)

app/socket/Pinger.scala

@@ -0,0 +1,11 @@
+package lila
+package socket
+
+final class Pinger {
+
+  private val uids = new memo.PingMemo(20 * 1000)
+
+  def apply(uid: String) {
+    uids putUnsafe uid
+  }
+}

app/socket/model.scala

@@ -3,3 +3,5 @@ package socket
 
 case object Close
 case object GetNbMembers
+case class Ping(uid: String)
+case object Cleanup

todo

@@ -1,2 +1,6 @@
 ping nbm
 back button
+accept rematch -> end up as spectator of the new game
+extract chess
+chat ban
+wrong number of players