Add custom Java Flight Recorder event monitoring

emulinker/src/main/java/org/emulinker/kaillera/master/client/MasterListUpdater.kt

@@ -5,6 +5,7 @@ import kotlin.time.Duration.Companion.minutes
 import kotlin.time.Duration.Companion.seconds
 import org.emulinker.config.RuntimeFlags
 import org.emulinker.kaillera.master.StatsCollector
+import org.emulinker.monitoring.JfrEvent
 import org.emulinker.util.TaskScheduler
 
 class MasterListUpdater(
@@ -34,14 +35,26 @@ class MasterListUpdater(
           initialDelay = 10.seconds,
           period = LIST_REPORTING_INTERVAL,
         ) {
-          if (flags.touchEmulinker) emuLinkerMasterUpdateTask.reportStatus()
-          if (flags.touchKaillera) kailleraMasterUpdateTask.reportStatus()
+          val e = JfrEvent.MasterListCheckin()
+          e.begin()
+          try {
+            if (flags.touchEmulinker) emuLinkerMasterUpdateTask.reportStatus()
+            if (flags.touchKaillera) kailleraMasterUpdateTask.reportStatus()
+          } finally {
+            e.commit()
+          }
           statsCollector.clearStartedGamesList()
         }
     }
     serverCheckinJob =
       taskScheduler.scheduleRepeating(initialDelay = 10.seconds, period = CHECKIN_INTERVAL) {
-        serverCheckinTask.reportStatus()
+        val e = JfrEvent.ElkCheckin()
+        e.begin()
+        try {
+          serverCheckinTask.reportStatus()
+        } finally {
+          e.commit()
+        }
       }
   }
 

emulinker/src/main/java/org/emulinker/kaillera/master/client/ServerCheckinTask.kt

@@ -10,7 +10,6 @@ import java.net.URL
 import java.util.Locale
 import java.util.concurrent.TimeUnit.HOURS
 import kotlinx.serialization.Serializable
-import kotlinx.serialization.encodeToString
 import kotlinx.serialization.json.Json
 import org.emulinker.config.RuntimeFlags
 import org.emulinker.kaillera.master.PublicServerInformation

emulinker/src/main/java/org/emulinker/kaillera/model/KailleraUser.kt

@@ -23,6 +23,7 @@ import org.emulinker.kaillera.model.event.UserQuitEvent
 import org.emulinker.kaillera.model.event.UserQuitGameEvent
 import org.emulinker.kaillera.model.exception.*
 import org.emulinker.kaillera.model.impl.KailleraGameImpl
+import org.emulinker.monitoring.JfrEvent
 import org.emulinker.util.CircularVariableSizeByteArrayBuffer
 import org.emulinker.util.EmuLang
 import org.emulinker.util.TimeOffsetCache
@@ -45,6 +46,9 @@ class KailleraUser(
 ) {
   var inStealthMode = false
 
+  private val loginJfrEvent: JfrEvent.UserLogin =
+    JfrEvent.UserLogin(userId = id, ip = connectSocketAddress.toString()).also { it.begin() }
+
   /** Example: "Project 64k 0.13 (01 Aug 2003)" */
   var clientType: String? = null
     set(clientType) {
@@ -250,7 +254,11 @@ class KailleraUser(
   @Synchronized
   fun login(): Result<Unit> {
     updateLastActivity()
-    return server.login(this)
+    val result = server.login(this)
+    loginJfrEvent.username = name ?: ""
+    loginJfrEvent.successful = result.isSuccess
+    loginJfrEvent.commit()
+    return result
   }
 
   @Throws(ChatException::class, FloodException::class)
@@ -271,25 +279,28 @@ class KailleraUser(
   }
 
   @Throws(CreateGameException::class, FloodException::class)
-  fun createGame(romName: String?): KailleraGame? {
-    updateLastActivity()
-    if (server.getUser(id) == null) {
-      logger.atSevere().log("%s create game failed: User don't exist!", this)
-      return null
-    }
-    if (status == UserStatus.PLAYING) {
-      logger.atWarning().log("%s create game failed: User status is Playing!", this)
-      throw CreateGameException(EmuLang.getString("KailleraUserImpl.CreateGameErrorAlreadyInGame"))
-    } else if (status == UserStatus.CONNECTING) {
-      logger.atWarning().log("%s create game failed: User status is Connecting!", this)
-      throw CreateGameException(
-        EmuLang.getString("KailleraUserImpl.CreateGameErrorNotFullyConnected")
-      )
+  fun createGame(romName: String?): KailleraGame? =
+    JfrEvent.CreateGame().record {
+      updateLastActivity()
+      if (server.getUser(id) == null) {
+        logger.atSevere().log("%s create game failed: User don't exist!", this)
+        return null
+      }
+      if (status == UserStatus.PLAYING) {
+        logger.atWarning().log("%s create game failed: User status is Playing!", this)
+        throw CreateGameException(
+          EmuLang.getString("KailleraUserImpl.CreateGameErrorAlreadyInGame")
+        )
+      } else if (status == UserStatus.CONNECTING) {
+        logger.atWarning().log("%s create game failed: User status is Connecting!", this)
+        throw CreateGameException(
+          EmuLang.getString("KailleraUserImpl.CreateGameErrorNotFullyConnected")
+        )
+      }
+      val game = server.createGame(this, romName)
+      lastCreateGameTime = System.currentTimeMillis()
+      return game
     }
-    val game = server.createGame(this, romName)
-    lastCreateGameTime = System.currentTimeMillis()
-    return game
-  }
 
   @Synchronized
   @Throws(
@@ -298,11 +309,12 @@ class KailleraUser(
     QuitGameException::class,
     CloseGameException::class,
   )
-  fun quit(message: String?) {
-    updateLastActivity()
-    server.quit(this, message)
-    loggedIn = false
-  }
+  fun quit(message: String?) =
+    JfrEvent.QuitServer().record {
+      updateLastActivity()
+      server.quit(this, message)
+      loggedIn = false
+    }
 
   fun lagAttributedToUser(): Duration =
     (totalDriftNs - (totalDriftCache.getDelayedValue() ?: 0)).nanoseconds.absoluteValue
@@ -418,16 +430,17 @@ class KailleraUser(
 
   @Synchronized
   @Throws(StartGameException::class)
-  fun startGame() {
-    resetLag()
-    updateLastActivity()
-    val game = this.game
-    if (game == null) {
-      logger.atWarning().log("%s start game failed: Not in a game", this)
-      throw StartGameException(EmuLang.getString("KailleraUserImpl.StartGameErrorNotInGame"))
+  fun startGame() =
+    JfrEvent.GameStart(gameId = id).record {
+      resetLag()
+      updateLastActivity()
+      val game = this.game
+      if (game == null) {
+        logger.atWarning().log("%s start game failed: Not in a game", this)
+        throw StartGameException(EmuLang.getString("KailleraUserImpl.StartGameErrorNotInGame"))
+      }
+      game.start(this)
     }
-    game.start(this)
-  }
 
   @Synchronized
   @Throws(UserReadyException::class)

emulinker/src/main/java/org/emulinker/monitoring/JfrEvents.kt

@@ -0,0 +1,56 @@
+package org.emulinker.monitoring
+
+import jdk.jfr.Description
+import jdk.jfr.Event
+import jdk.jfr.Label
+import jdk.jfr.Name
+
+sealed class JfrEvent : Event() {
+
+  inline fun <T> record(block: () -> T): T {
+    begin()
+    return try {
+      block()
+    } finally {
+      commit()
+    }
+  }
+
+  @Name("User Login")
+  @Description("A user joined the server")
+  class UserLogin(
+    @field:Label("User ID") var userId: Int,
+    @field:Label("User IP Address") val ip: String,
+  ) : JfrEvent() {
+
+    @Label("Username") var username: String = ""
+
+    @Label("Successful") var successful: Boolean = false
+  }
+
+  @Name("Server Lists Check-in")
+  @Description("Reported server status for public game lists")
+  class MasterListCheckin : JfrEvent()
+
+  @Name("ELK Check-in")
+  @Description("Checked in with central EmuLinker-K server")
+  class ElkCheckin : JfrEvent()
+
+  @Name("Create Game")
+  @Description("A user created a new game in the server")
+  class CreateGame : JfrEvent()
+
+  @Name("Stop Game")
+  @Description("A user created a new game in the server")
+  class StopGame : JfrEvent()
+
+  class DropGame : JfrEvent()
+
+  @Name("Game Start") class GameStart(@field:Label("Game ID") var gameId: Int) : JfrEvent()
+
+  class QuitServer : JfrEvent()
+
+  class GameChat : JfrEvent()
+
+  class ServerChat : JfrEvent()
+}