feat: Switch from coroutines to virtual threads

build.gradle.kts

@@ -3,7 +3,6 @@ plugins {
     kotlin("plugin.spring") version "2.2.0"
     id("org.springframework.boot") version "3.4.4"
     id("io.spring.dependency-management") version "1.1.7"
-    id("com.google.cloud.tools.jib") version "3.4.5"
     id("com.diffplug.spotless") version "7.0.3"
 }
 
@@ -55,10 +54,3 @@ spotless {
     ktfmt("0.54").kotlinlangStyle()
   }
 }
-
-jib {
-    container {
-        // disable spring devtools
-        jvmFlags = listOf("-Dspring.devtools.restart.enabled=false")
-    }
-}

src/main/kotlin/com/pischule/memevizor/bot/BotConfiguration.kt

@@ -13,6 +13,8 @@ import com.pischule.memevizor.bot.handler.ThisCommandHandlerService
 import com.pischule.memevizor.util.getMedia
 import io.github.oshai.kotlinlogging.KotlinLogging
 import io.github.oshai.kotlinlogging.withLoggingContext
+import java.util.concurrent.ExecutorService
+import java.util.concurrent.Executors
 import org.springframework.boot.context.properties.EnableConfigurationProperties
 import org.springframework.context.annotation.Bean
 import org.springframework.context.annotation.Configuration
@@ -35,13 +37,17 @@ class BotConfiguration(
         }
     }
 
+    @Bean fun botPollingExecutor(): ExecutorService = Executors.newSingleThreadExecutor()
+
+    @Bean fun botHandlerExecutor(): ExecutorService = Executors.newVirtualThreadPerTaskExecutor()
+
     private fun Bot.Builder.setupDispatchers() = dispatch {
-        message { withLogAndErrorHandling(message) { thisCommandHandlerService.create(this) } }
+        message { handleMessage(message) { thisCommandHandlerService.create(this) } }
         photos { handleMedia() }
         video { handleMedia() }
         videoNote { handleMedia() }
         command("whoami") {
-            withLogAndErrorHandling(message) {
+            handleMessage(message) {
                 bot.sendMessage(
                         chatId = ChatId.fromId(message.chat.id),
                         text = "chatId: `${message.chat.id}`\nuserId: `${message.from?.id}`",
@@ -52,22 +58,24 @@ class BotConfiguration(
         }
     }
 
-    private suspend fun MediaHandlerEnvironment<*>.handleMedia() {
-        withLogAndErrorHandling(message) { mediaHandlerService.create(this) }
+    private fun MediaHandlerEnvironment<*>.handleMedia() {
+        handleMessage(message) { mediaHandlerService.create(this) }
     }
 
-    private suspend fun withLogAndErrorHandling(message: Message, block: suspend () -> Unit) {
-        withLoggingContext(
-            "message_id" to message.messageId.toString(),
-            "chat_id" to message.chat.id.toString(),
-            "from_user_id" to message.from?.id.toString(),
-            "from_user_username" to message.from?.username.toString(),
-            "file_id" to (message.getMedia()?.fileId),
-        ) {
-            try {
-                block.invoke()
-            } catch (e: Exception) {
-                logger.error(e) { "Error while handling message" }
+    private fun handleMessage(message: Message, block: () -> Unit) {
+        botHandlerExecutor().execute {
+            withLoggingContext(
+                "message_id" to message.messageId.toString(),
+                "chat_id" to message.chat.id.toString(),
+                "from_user_id" to message.from?.id.toString(),
+                "from_user_username" to message.from?.username.toString(),
+                "file_id" to (message.getMedia()?.fileId),
+            ) {
+                try {
+                    block.invoke()
+                } catch (e: Exception) {
+                    logger.error(e) { "Error while handling message" }
+                }
             }
         }
     }

src/main/kotlin/com/pischule/memevizor/bot/BotService.kt

@@ -4,29 +4,23 @@ import com.github.kotlintelegrambot.Bot
 import io.github.oshai.kotlinlogging.KotlinLogging
 import jakarta.annotation.PostConstruct
 import jakarta.annotation.PreDestroy
+import java.util.concurrent.ExecutorService
 import org.springframework.stereotype.Service
 
 private val logger = KotlinLogging.logger {}
 
 @Service
-class BotService(private val bot: Bot) {
-    private var pollingThread: Thread? = null
+class BotService(private val bot: Bot, private val botPollingExecutor: ExecutorService) {
 
     @PostConstruct
     fun start() {
-        pollingThread =
-            Thread { bot.startPolling() }
-                .apply {
-                    name = "telegram-bot-polling"
-                    start()
-                }
+        botPollingExecutor.submit(bot::startPolling)
         logger.info { "Bot service started" }
     }
 
     @PreDestroy
     fun stop() {
         bot.stopPolling()
-        pollingThread?.join(1000)
         logger.info { "Bot service stopped" }
     }
 }

src/main/kotlin/com/pischule/memevizor/bot/handler/MediaHandlerService.kt

@@ -12,7 +12,7 @@ private val logger = KotlinLogging.logger {}
 @Service
 class MediaHandlerService(private val botProps: BotProps) {
 
-    suspend fun create(env: MediaHandlerEnvironment<*>) {
+    fun create(env: MediaHandlerEnvironment<*>) {
         if (shouldForwardMessage(env)) {
             forwardMessage(env)
         }
@@ -24,7 +24,7 @@ class MediaHandlerService(private val botProps: BotProps) {
         return env.message.chat.id != botProps.forwardChatId
     }
 
-    private suspend fun forwardMessage(env: MediaHandlerEnvironment<*>) {
+    private fun forwardMessage(env: MediaHandlerEnvironment<*>) {
         env.bot
             .forwardMessage(
                 chatId = ChatId.fromId(botProps.forwardChatId),
@@ -37,7 +37,7 @@ class MediaHandlerService(private val botProps: BotProps) {
             )
     }
 
-    private suspend fun reactToMessage(env: MediaHandlerEnvironment<*>, emoji: String) {
+    private fun reactToMessage(env: MediaHandlerEnvironment<*>, emoji: String) {
         env.bot
             .setMessageReaction(
                 chatId = ChatId.fromId(env.message.chat.id),

src/main/kotlin/com/pischule/memevizor/bot/handler/ThisCommandHandlerService.kt

@@ -23,7 +23,7 @@ class ThisCommandHandlerService(
     private val confirmCommands = listOf("this", "!soxok")
     private val mediaFileName = "media"
 
-    suspend fun create(env: MessageHandlerEnvironment) {
+    fun create(env: MessageHandlerEnvironment) {
         if (!shouldHandleMessage(env)) return
 
         val replyToMessage = env.message.replyToMessage ?: return
@@ -54,7 +54,7 @@ class ThisCommandHandlerService(
         return isApprover && isConfirmCommand
     }
 
-    private suspend fun reactToMessage(env: MessageHandlerEnvironment, emoji: String) {
+    private fun reactToMessage(env: MessageHandlerEnvironment, emoji: String) {
         env.bot
             .setMessageReaction(
                 chatId = ChatId.fromId(env.message.chat.id),