From af4efb40b3c3d216dc86d09586ac67be91310eca Mon Sep 17 00:00:00 2001
From: Thibault Duplessis <t@lichess.org>
Date: Fri, 26 Nov 2021 17:37:45 +0100
Subject: [PATCH] cloud eval live setting

---
 app/controllers/Dev.scala                     |  3 ++-
 modules/evalCache/src/main/Env.scala          |  7 ++++++
 .../evalCache/src/main/EvalCacheUpgrade.scala | 22 ++++++++++---------
 3 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/app/controllers/Dev.scala b/app/controllers/Dev.scala
index 2f6d4460b0..fff8b67fe9 100644
--- a/app/controllers/Dev.scala
+++ b/app/controllers/Dev.scala
@@ -27,7 +27,8 @@ final class Dev(env: Env) extends LilaController(env) {
     env.noDelaySecretSetting,
     env.featuredTeamsSetting,
     env.prizeTournamentMakers,
-    env.pieceImageExternal
+    env.pieceImageExternal,
+    env.evalCache.enable
   )
 
   def settings =
diff --git a/modules/evalCache/src/main/Env.scala b/modules/evalCache/src/main/Env.scala
index 6ea164e8f4..97c5df1c7f 100644
--- a/modules/evalCache/src/main/Env.scala
+++ b/modules/evalCache/src/main/Env.scala
@@ -16,6 +16,7 @@ final class Env(
     userRepo: lila.user.UserRepo,
     yoloDb: lila.db.AsyncDb @@ lila.db.YoloDb,
     cacheApi: lila.memo.CacheApi,
+    settingStore: lila.memo.SettingStore.Builder,
     scheduler: akka.actor.Scheduler
 )(implicit
     ec: scala.concurrent.ExecutionContext,
@@ -27,6 +28,12 @@ final class Env(
 
   private lazy val truster = wire[EvalCacheTruster]
 
+  lazy val enable = settingStore[Boolean](
+    "useCeval",
+    default = true,
+    text = "Enable cloud eval (disable in case of server trouble)".some
+  )
+
   private lazy val upgrade = wire[EvalCacheUpgrade]
 
   lazy val api: EvalCacheApi = wire[EvalCacheApi]
diff --git a/modules/evalCache/src/main/EvalCacheUpgrade.scala b/modules/evalCache/src/main/EvalCacheUpgrade.scala
index 1b3066d623..ce31bb558b 100644
--- a/modules/evalCache/src/main/EvalCacheUpgrade.scala
+++ b/modules/evalCache/src/main/EvalCacheUpgrade.scala
@@ -9,12 +9,13 @@ import lila.socket.Socket
 import lila.memo.ExpireCallbackMemo
 
 import scala.collection.mutable
+import lila.memo.SettingStore
 
 /* Upgrades the user's eval when a better one becomes available,
  * by remembering the last evalGet of each socket member,
  * and listening to new evals stored.
  */
-final private class EvalCacheUpgrade(scheduler: akka.actor.Scheduler)(implicit
+final private class EvalCacheUpgrade(setting: SettingStore[Boolean], scheduler: akka.actor.Scheduler)(implicit
     ec: scala.concurrent.ExecutionContext,
     mode: play.api.Mode
 ) {
@@ -26,17 +27,18 @@ final private class EvalCacheUpgrade(scheduler: akka.actor.Scheduler)(implicit
 
   private val upgradeMon = lila.mon.evalCache.upgrade
 
-  def register(sri: Socket.Sri, variant: Variant, fen: FEN, multiPv: Int, path: String)(push: Push): Unit = {
-    members get sri.value foreach { wm =>
-      unregisterEval(wm.setupId, sri)
+  def register(sri: Socket.Sri, variant: Variant, fen: FEN, multiPv: Int, path: String)(push: Push): Unit =
+    if (setting.get()) {
+      members get sri.value foreach { wm =>
+        unregisterEval(wm.setupId, sri)
+      }
+      val setupId = makeSetupId(variant, fen, multiPv)
+      members += (sri.value -> WatchingMember(push, setupId, path))
+      evals += (setupId     -> (~evals.get(setupId) + sri.value))
+      expirableSris put sri.value
     }
-    val setupId = makeSetupId(variant, fen, multiPv)
-    members += (sri.value -> WatchingMember(push, setupId, path))
-    evals += (setupId     -> (~evals.get(setupId) + sri.value))
-    expirableSris put sri.value
-  }
 
-  def onEval(input: EvalCacheEntry.Input, sri: Socket.Sri): Unit = {
+  def onEval(input: EvalCacheEntry.Input, sri: Socket.Sri): Unit = if (setting.get()) {
     (1 to input.eval.multiPv) flatMap { multiPv =>
       evals get makeSetupId(input.id.variant, input.fen, multiPv)
     } foreach { sris =>