send empty frames for ping; keep bot player alive in the game socket

app/controllers/Bot.scala

@@ -14,7 +14,7 @@ object Bot extends LilaController {
     WithMyBotGame(id, me) { pov =>
       RequireHttp11(req) {
         lila.game.GameRepo.withInitialFen(pov.game) map { wf =>
-          Ok.chunked(Env.bot.gameStateStream(wf))
+          Ok.chunked(Env.bot.gameStateStream(me, wf, pov.color))
         }
       }
     }

modules/api/src/main/EventStream.scala

@@ -22,7 +22,7 @@ final class EventStream(
 
     var stream: Option[ActorRef] = None
 
-    val enumerator = Concurrent.unicast[JsObject](
+    val enumerator = Concurrent.unicast[Option[JsObject]](
       onStart = channel => {
         val actor = system.actorOf(Props(new Actor {
 
@@ -34,9 +34,11 @@ final class EventStream(
 
             case SetOnline =>
               setOnline(me.id)
-              context.system.scheduler.scheduleOnce(6 second, self, SetOnline)
-              // gotta send a message to check if the client has disconnected
-              channel push Json.obj("up" -> true)
+              context.system.scheduler.scheduleOnce(6 second) {
+                // gotta send a message to check if the client has disconnected
+                channel push None
+                self ! SetOnline
+              }
 
             case UserStartGame(userId, game) if userId == me.id => pushGameStart(game)
 
@@ -46,12 +48,12 @@ final class EventStream(
           def pushGameStart(game: Game) = channel push Json.obj(
             "type" -> "gameStart",
             "game" -> Json.obj("id" -> game.id)
-          )
+          ).some
 
           def pushChallenge(c: lila.challenge.Challenge) = channel push Json.obj(
             "type" -> "challenge",
             "challenge" -> challengeJsonView(none)(c)
-          )
+          ).some
         }))
         system.lilaBus.subscribe(actor, Symbol(s"userStartGame:${me.id}"), 'challenge)
         stream = actor.some
@@ -59,6 +61,6 @@ final class EventStream(
       onComplete = onComplete(stream, system)
     )
 
-    enumerator &> stringify
+    enumerator &> stringifyOrEmpty
   }
 }

modules/bot/src/main/Env.scala

@@ -5,12 +5,17 @@ import akka.actor._
 final class Env(
     system: ActorSystem,
     hub: lila.hub.Env,
+    onlineUserIds: lila.memo.ExpireSetMemo,
     lightUserApi: lila.user.LightUserApi
 ) {
 
   lazy val jsonView = new BotJsonView(lightUserApi)
 
-  lazy val gameStateStream = new GameStateStream(system, jsonView)
+  lazy val gameStateStream = new GameStateStream(
+    system,
+    jsonView,
+    hub.socket.round
+  )
 
   lazy val player = new BotPlayer(
     roundMap = hub.actor.roundMap
@@ -22,6 +27,7 @@ object Env {
   lazy val current: Env = "bot" boot new Env(
     system = lila.common.PlayApp.system,
     hub = lila.hub.Env.current,
+    onlineUserIds = lila.user.Env.current.onlineUserIdMemo,
     lightUserApi = lila.user.Env.current.lightUserApi
   )
 }

modules/bot/src/main/GameStateStream.scala

@@ -1,5 +1,6 @@
 package lila.bot
 
+import scala.concurrent.duration._
 import akka.actor._
 import play.api.libs.iteratee._
 import play.api.libs.json._
@@ -9,39 +10,51 @@ import chess.format.FEN
 import lila.game.actorApi.{ FinishGame, AbortedBy }
 import lila.game.{ Game, GameRepo }
 import lila.hub.actorApi.round.MoveEvent
+import lila.hub.actorApi.map.Tell
+import lila.socket.actorApi.BotPing
 import lila.user.User
 
 final class GameStateStream(
     system: ActorSystem,
-    jsonView: BotJsonView
+    jsonView: BotJsonView,
+    roundSocketHub: ActorSelection
 ) {
 
   import lila.common.HttpStream._
 
-  def apply(init: Game.WithInitialFen): Enumerator[String] = {
+  def apply(me: User, init: Game.WithInitialFen, as: chess.Color): Enumerator[String] = {
 
     val id = init.game.id
 
     var stream: Option[ActorRef] = None
 
-    val enumerator = Concurrent.unicast[JsObject](
+    val enumerator = Concurrent.unicast[Option[JsObject]](
       onStart = channel => {
         val actor = system.actorOf(Props(new Actor {
 
           jsonView gameFull init foreach { json =>
             // prepend the full game JSON at the start of the stream
-            channel push json
+            channel push json.some
             // close stream if game is over
             if (init.game.finished) channel.eofAndEnd()
           }
+          self ! SetOnline
 
           def receive = {
             case g: Game if g.id == id => pushState(g)
             case FinishGame(g, _, _) if g.id == id => terminate
             case AbortedBy(pov) if pov.gameId == id => terminate
+
+            case SetOnline =>
+              roundSocketHub ! Tell(init.game.id, BotPing(as))
+              context.system.scheduler.scheduleOnce(6 second) {
+                // gotta send a message to check if the client has disconnected
+                channel push None
+                self ! SetOnline
+              }
           }
 
-          def pushState(g: Game) = jsonView gameState Game.WithInitialFen(g, init.fen) map channel.push
+          def pushState(g: Game) = jsonView gameState Game.WithInitialFen(g, init.fen) map some map channel.push
           def terminate = channel.eofAndEnd()
         }))
         system.lilaBus.subscribe(actor, Symbol(s"moveGame:$id"), 'finishGame, 'abortGame)
@@ -50,6 +63,6 @@ final class GameStateStream(
       onComplete = onComplete(stream, system)
     )
 
-    enumerator &> stringify
+    enumerator &> stringifyOrEmpty
   }
 }

modules/common/src/main/HttpStream.scala

@@ -11,6 +11,12 @@ object HttpStream {
       Json.stringify(js) + "\n"
     }
 
+  val stringifyOrEmpty =
+    Enumeratee.map[Option[JsObject]].apply[String] {
+      case None => "\n"
+      case Some(js) => Json.stringify(js) + "\n"
+    }
+
   def onComplete(stream: Option[ActorRef], system: ActorSystem) =
     stream foreach { actor =>
       system.lilaBus.unsubscribe(actor)

modules/round/src/main/Socket.scala

@@ -141,6 +141,8 @@ private[round] final class Socket(
         (history getEventsSince v).fold(resyncNow(member))(batch(member, _))
       }
 
+    case BotPing(color) => playerDo(color.pp("bot ping"), _.ping)
+
     case Bye(color) => playerDo(color, _.setBye)
 
     case Broom =>

modules/socket/src/main/actorApi.scala

@@ -11,6 +11,7 @@ case class Connected[M <: SocketMember](
 )
 case class Sync(uid: String, friends: List[String])
 case class Ping(uid: String, version: Option[Int], lagCentis: Option[Centis])
+case class BotPing(color: chess.Color)
 
 object Ping {
   def apply(uid: Socket.Uid, o: JsObject): Ping =