Fix graceful shutdown

settings.sample.yaml

@@ -23,7 +23,7 @@
 # The size in mebibytes of the cache
 # You can use megabytes instead in a pinch,
 # but just know the two are **NOT** the same.
-max_cache_size_in_mebibytes: 1024
+max_cache_size_in_mebibytes: 0
 
 # Optional settings for fancy geoip analytics
 metrics_settings:

src/main/kotlin/mdnet/Main.kt

@@ -32,7 +32,11 @@ object Main {
 
     @JvmStatic
     fun main(args: Array<String>) {
+        try {
             CommandLine(ClientArgs()).execute(*args)
+        } catch (e: Throwable) {
+            LOGGER.error(e) { "Critical Error " }
+        }
     }
 
     fun dieWithError(e: Throwable): Nothing {

src/main/kotlin/mdnet/MangaDexClient.kt

@@ -175,8 +175,14 @@ class MangaDexClient(private val settingsFile: File, databaseFile: File, cacheFo
 
             storage.maxSize = (newSettings.maxCacheSizeInMebibytes * 1024 * 1024 * 0.95).toLong()
 
+            if (imageServer != null) {
                 stopImageServer()
+            }
+            try {
                 startImageServer()
+            } catch (e: Exception) {
+                LOGGER.warn(e) { "Error starting the image server" }
+            }
         } catch (e: UnrecognizedPropertyException) {
             LOGGER.warn { "Settings file is invalid: '$e.propertyName' is not a valid setting" }
         } catch (e: JsonProcessingException) {
@@ -189,8 +195,8 @@ class MangaDexClient(private val settingsFile: File, databaseFile: File, cacheFo
     }
 
     private fun validateSettings(settings: ClientSettings) {
-        if (settings.maxCacheSizeInMebibytes < 1024) {
-            throw ClientSettingsException("Config Error: Invalid max cache size, must be >= 1024 MiB (1GiB)")
+        if (settings.maxCacheSizeInMebibytes < 20480) {
+            throw ClientSettingsException("Config Error: Invalid max cache size, must be >= 20480 MiB (20 GiB)")
         }
 
         fun isSecretValid(clientSecret: String): Boolean {

src/main/kotlin/mdnet/ServerManager.kt

@@ -58,7 +58,7 @@ object Shutdown : State()
 data class GracefulStop(
     val lastRunning: Running,
     val counts: Int = 0,
-    val nextState: State = Uninitialized,
+    val nextState: State,
     val action: () -> Unit = {}
 ) : State()
 
@@ -193,7 +193,7 @@ class ServerManager(
                         if (settings.serverSettings.maxMebibytesPerHour != 0L && settings.serverSettings.maxMebibytesPerHour * 1024 * 1024 /* MiB to bytes */ < currentBytesSent) {
                             LOGGER.info { "Stopping image server as hourly bandwidth limit reached" }
 
-                            this.state = GracefulStop(lastRunning = state)
+                            this.state = GracefulStop(lastRunning = state, nextState = Uninitialized)
                         } else {
                             pingControl()
                         }
@@ -245,7 +245,7 @@ class ServerManager(
             if (!state.settings.logicalEqual(newSettings)) {
                 LOGGER.info { "Doing internal restart of HTTP server to refresh settings" }
 
-                this.state = GracefulStop(lastRunning = state) {
+                this.state = GracefulStop(lastRunning = state, nextState = Uninitialized) {
                     loginAndStartServer()
                 }
             }

src/main/kotlin/mdnet/netty/ApplicationNetty.kt

@@ -77,9 +77,9 @@ sealed class NettyTransport(threads: Int) {
     )
 
     fun shutdownGracefully() {
-        bossGroup.shutdownGracefully()
-        workerGroup.shutdownGracefully()
-        executor.shutdownGracefully()
+        bossGroup.shutdownGracefully().sync()
+        workerGroup.shutdownGracefully().sync()
+        executor.shutdownGracefully().sync()
     }
 
     private class NioTransport(threads: Int) : NettyTransport(threads) {
@@ -111,6 +111,7 @@ sealed class NettyTransport(threads: Int) {
             LOGGER.info { "Choosing a transport using $threadsToUse threads" }
 
             if (name.startsWith("linux")) {
+                if (!SystemPropertyUtil.get("no-iouring").toBoolean()) {
                     if (IOUring.isAvailable()) {
                         LOGGER.info { "Using IOUring transport" }
                         return IOUringTransport(threadsToUse)
@@ -119,7 +120,9 @@ sealed class NettyTransport(threads: Int) {
                             "IOUring transport not available"
                         }
                     }
+                }
 
+                if (!SystemPropertyUtil.get("no-epoll").toBoolean()) {
                     if (Epoll.isAvailable()) {
                         LOGGER.info { "Using Epoll transport" }
                         return EpollTransport(threadsToUse)
@@ -129,6 +132,7 @@ sealed class NettyTransport(threads: Int) {
                         }
                     }
                 }
+            }
 
             LOGGER.info { "Using Nio transport" }
             return NioTransport(threadsToUse)
@@ -144,9 +148,7 @@ class Netty(
     override fun toServer(httpHandler: HttpHandler): Http4kServer = object : Http4kServer {
         private val transport = NettyTransport.bestForPlatform(serverSettings.threads)
 
-        private lateinit var closeFuture: ChannelFuture
-        private lateinit var address: InetSocketAddress
-
+        private lateinit var channel: Channel
         private val burstLimiter = object : GlobalTrafficShapingHandler(
             transport.workerGroup, serverSettings.maxKilobitsPerSecond * 1000L / 8L, 0, 100
         ) {
@@ -209,14 +211,12 @@ class Netty(
                 .option(ChannelOption.SO_BACKLOG, 1000)
                 .childOption(ChannelOption.SO_KEEPALIVE, true)
 
-            val channel = bootstrap.bind(InetSocketAddress(serverSettings.hostname, serverSettings.port)).sync().channel()
-            address = channel.localAddress() as InetSocketAddress
-            closeFuture = channel.closeFuture()
+            channel = bootstrap.bind(InetSocketAddress(serverSettings.hostname, serverSettings.port)).sync().channel()
         }
 
         override fun stop() = apply {
-            closeFuture.cancel(false)
             transport.shutdownGracefully()
+            channel.closeFuture().sync()
         }
 
         override fun port(): Int = serverSettings.port