shared event executor group between server and clients

- improved documentation
- closed memcache client's thread pools

README.md

@@ -66,11 +66,18 @@ buildCache {
         url = 'https://rbcs.example.com/'
         push = true
         allowInsecureProtocol = false
+        // The credentials block is only required if you enable 
+        // HTTP basic authentication on RBCS
+        credentials {
+            username = 'build-cache-user'
+            password = 'some-complicated-password'
+        }
     }
 }
 ```
 
-alternatively you can add this to `${GRADLE_HOME}/init.gradle`
+alternatively you can add this to `${GRADLE_HOME}/init.gradle` to configure the remote cache
+at the system level
 
 ```groovy
 gradle.settingsEvaluated { settings ->
@@ -79,14 +86,51 @@ gradle.settingsEvaluated { settings ->
             url = 'https://rbcs.example.com/'
             push = true
             allowInsecureProtocol = false
+            // The credentials block is only required if you enable 
+            // HTTP basic authentication on RBCS
+            credentials {
+                username = 'build-cache-user'
+                password = 'some-complicated-password'
+            }
         }
     }
 }
 ```
 
+add `org.gradle.caching=true` to your `<project>/gradle.properties` or run gradle with `--build-cache`.
+
+Read [Gradle documentation](https://docs.gradle.org/current/userguide/build_cache.html) for more detailed information.
+
 ### Using RBCS with Maven
 
+1. Create an `extensions.xml` in `<project>/.mvn/extensions.xml` with the following content
+  ```xml
+  <extensions xmlns="http://maven.apache.org/EXTENSIONS/1.1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+            xsi:schemaLocation="http://maven.apache.org/EXTENSIONS/1.1.0 https://maven.apache.org/xsd/core-extensions-1.0.0.xsd">
+      <extension>
+          <groupId>org.apache.maven.extensions</groupId>
+          <artifactId>maven-build-cache-extension</artifactId>
+          <version>1.2.0</version>
+      </extension>
+  </extensions>
+  ```
+2. Copy [maven-build-cache-config.xml](https://maven.apache.org/extensions/maven-build-cache-extension/maven-build-cache-config.xml) into `<project>/.mvn/` folder
+3. Edit the `cache/configuration/remote` element
+  ```xml
+    <remote enabled="true" id="rbcs">
+        <url>https://rbcs.example.com/</url>
+    </remote>
+  ```
+4. Run maven with
+  ```bash
+    mvn -Dmaven.build.cache.enabled=true -Dmaven.build.cache.debugOutput=true -Dmaven.build.cache.remote.save.enabled=true package
+  ```
+
+Alternatively you can set those properties in your `<project>/pom.xml`
+
+
 Read [here](https://maven.apache.org/extensions/maven-build-cache-extension/remote-cache.html)
+for more informations
 
 ## FAQ
 ### Why should I use a build cache?

build.gradle

@@ -14,9 +14,7 @@ allprojects { subproject ->
         if(project.currentTag.isPresent()) {
             version = project.currentTag.map { it[0] }.get()
         } else {
-            version = project.gitRevision.map { gitRevision ->
-                "${getProperty('rbcs.version')}.${gitRevision[0..10]}"
-            }.get()
+            version = "${getProperty('rbcs.version')}-SNAPSHOT"
         }
 
     repositories {
@@ -24,7 +22,6 @@ allprojects { subproject ->
             url = getProperty('gitea.maven.url')
             content {
                 includeModule 'net.woggioni', 'jwo'
-                includeModule 'net.woggioni', 'xmemcached'
                 includeGroup 'com.lys'
             }
         }

rbcs-api/build.gradle

@@ -5,6 +5,7 @@ plugins {
 }
 
 dependencies {
+    api catalog.netty.common
     api catalog.netty.buffer
     api catalog.netty.handler
 }

rbcs-api/src/main/java/module-info.java

@@ -4,6 +4,7 @@ module net.woggioni.rbcs.api {
     requires io.netty.buffer;
     requires io.netty.handler;
     requires io.netty.transport;
+    requires io.netty.common;
     exports net.woggioni.rbcs.api;
     exports net.woggioni.rbcs.api.exception;
     exports net.woggioni.rbcs.api.message;

rbcs-api/src/main/java/net/woggioni/rbcs/api/AsyncCloseable.java

@@ -0,0 +1,13 @@
+package net.woggioni.rbcs.api;
+
+import java.util.concurrent.CompletableFuture;
+
+public interface AsyncCloseable extends AutoCloseable {
+
+    CompletableFuture<Void> asyncClose();
+
+    @Override
+    default void close() throws Exception {
+        asyncClose().get();
+    }
+}

rbcs-api/src/main/java/net/woggioni/rbcs/api/CacheHandlerFactory.java

@@ -1,7 +1,15 @@
 package net.woggioni.rbcs.api;
 
+import io.netty.channel.ChannelFactory;
 import io.netty.channel.ChannelHandler;
+import io.netty.channel.EventLoopGroup;
+import io.netty.channel.socket.DatagramChannel;
+import io.netty.channel.socket.SocketChannel;
 
-public interface CacheHandlerFactory extends AutoCloseable {
-    ChannelHandler newHandler();
+public interface CacheHandlerFactory extends AsyncCloseable {
+    ChannelHandler newHandler(
+            EventLoopGroup eventLoopGroup,
+            ChannelFactory<SocketChannel> socketChannelFactory,
+            ChannelFactory<DatagramChannel> datagramChannelFactory
+    );
 }

rbcs-api/src/main/java/net/woggioni/rbcs/api/Configuration.java

@@ -83,17 +83,6 @@ public class Configuration {
         Group extract(X509Certificate cert);
     }
 
-    @Value
-    public static class Throttling {
-        KeyStore keyStore;
-        TrustStore trustStore;
-        boolean verifyClients;
-    }
-
-    public enum ClientCertificate {
-        REQUIRED, OPTIONAL
-    }
-
     @Value
     public static class Tls {
         KeyStore keyStore;

rbcs-cli/build.gradle

@@ -9,6 +9,7 @@ plugins {
     id 'maven-publish'
 }
 
+import net.woggioni.gradle.envelope.EnvelopePlugin
 import net.woggioni.gradle.envelope.EnvelopeJarTask
 import net.woggioni.gradle.graalvm.NativeImageConfigurationTask
 import net.woggioni.gradle.graalvm.NativeImagePlugin
@@ -16,15 +17,6 @@ import net.woggioni.gradle.graalvm.NativeImageTask
 import net.woggioni.gradle.graalvm.JlinkPlugin
 import net.woggioni.gradle.graalvm.JlinkTask
 
-Property<String> mainModuleName = objects.property(String.class)
-mainModuleName.set('net.woggioni.rbcs.cli')
-Property<String> mainClassName = objects.property(String.class)
-mainClassName.set('net.woggioni.rbcs.cli.RemoteBuildCacheServerCli')
-
-tasks.named(JavaPlugin.COMPILE_JAVA_TASK_NAME, JavaCompile) {
-    options.javaModuleMainClass = mainClassName
-}
-
 configurations {
     release {
         transitive = false
@@ -34,13 +26,6 @@ configurations {
     }
 }
 
-envelopeJar {
-    mainModule = mainModuleName
-    mainClass = mainClassName
-
-    extraClasspath = ["plugins"]
-}
-
 dependencies {
     implementation catalog.jwo
     implementation catalog.slf4j.api
@@ -54,18 +39,24 @@ dependencies {
 //    runtimeOnly catalog.slf4j.simple
 }
 
-Provider<EnvelopeJarTask> envelopeJarTaskProvider = tasks.named('envelopeJar', EnvelopeJarTask.class) {
-//    systemProperties['java.util.logging.config.class'] = 'net.woggioni.rbcs.LoggingConfig'
-//    systemProperties['log.config.source'] = 'net/woggioni/rbcs/cli/logging.properties'
-//    systemProperties['java.util.logging.config.file'] = 'classpath:net/woggioni/rbcs/cli/logging.properties'
+
+Property<String> mainModuleName = objects.property(String.class)
+mainModuleName.set('net.woggioni.rbcs.cli')
+Property<String> mainClassName = objects.property(String.class)
+mainClassName.set('net.woggioni.rbcs.cli.RemoteBuildCacheServerCli')
+
+tasks.named(JavaPlugin.COMPILE_JAVA_TASK_NAME, JavaCompile) {
+    options.javaModuleMainClass = mainClassName
+}
+
+Provider<EnvelopeJarTask> envelopeJarTaskProvider = tasks.named(EnvelopePlugin.ENVELOPE_JAR_TASK_NAME, EnvelopeJarTask.class) {
+    mainModule = mainModuleName
+    mainClass = mainClassName
+
+    extraClasspath = ["plugins"]
+
     systemProperties['logback.configurationFile'] = 'classpath:net/woggioni/rbcs/cli/logback.xml'
     systemProperties['io.netty.leakDetectionLevel'] = 'DISABLED'
-
-//    systemProperties['org.slf4j.simpleLogger.showDateTime'] = 'true'
-//    systemProperties['org.slf4j.simpleLogger.defaultLogLevel'] = 'debug'
-//    systemProperties['org.slf4j.simpleLogger.log.com.google.code.yanf4j'] = 'warn'
-//    systemProperties['org.slf4j.simpleLogger.log.net.rubyeye.xmemcached'] = 'warn'
-//    systemProperties['org.slf4j.simpleLogger.dateTimeFormat'] = 'yyyy-MM-dd\'T\'HH:mm:ss.SSSZ'
 }
 
 tasks.named(NativeImagePlugin.CONFIGURE_NATIVE_IMAGE_TASK_NAME, NativeImageConfigurationTask) {

rbcs-common/src/main/kotlin/net/woggioni/rbcs/common/RBCS.kt

@@ -32,7 +32,7 @@ object RBCS {
 
     fun digest(
         data: ByteArray,
-        md: MessageDigest = MessageDigest.getInstance("MD5")
+        md: MessageDigest
     ): ByteArray {
         md.update(data)
         return md.digest()
@@ -40,7 +40,7 @@ object RBCS {
 
     fun digestString(
         data: ByteArray,
-        md: MessageDigest = MessageDigest.getInstance("MD5")
+        md: MessageDigest
     ): String {
         return JWO.bytesToHex(digest(data, md))
     }

rbcs-server-memcache/src/main/kotlin/net/woggioni/rbcs/server/memcache/MemcacheCacheConfiguration.kt

@@ -1,10 +1,20 @@
 package net.woggioni.rbcs.server.memcache
 
+import io.netty.channel.ChannelFactory
+import io.netty.channel.ChannelHandler
+import io.netty.channel.EventLoopGroup
+import io.netty.channel.pool.FixedChannelPool
+import io.netty.channel.socket.DatagramChannel
+import io.netty.channel.socket.SocketChannel
 import net.woggioni.rbcs.api.CacheHandlerFactory
 import net.woggioni.rbcs.api.Configuration
 import net.woggioni.rbcs.common.HostAndPort
 import net.woggioni.rbcs.server.memcache.client.MemcacheClient
 import java.time.Duration
+import java.util.concurrent.CompletableFuture
+import java.util.concurrent.ConcurrentHashMap
+import java.util.concurrent.atomic.AtomicInteger
+import java.util.concurrent.atomic.AtomicReference
 
 data class MemcacheCacheConfiguration(
     val servers: List<Server>,
@@ -12,7 +22,7 @@ data class MemcacheCacheConfiguration(
     val digestAlgorithm: String? = null,
     val compressionMode: CompressionMode? = null,
     val compressionLevel: Int,
-    val chunkSize : Int
+    val chunkSize: Int
 ) : Configuration.Cache {
 
     enum class CompressionMode {
@@ -23,19 +33,58 @@ data class MemcacheCacheConfiguration(
     }
 
     data class Server(
-        val endpoint : HostAndPort,
-        val connectionTimeoutMillis : Int?,
-        val maxConnections : Int
+        val endpoint: HostAndPort,
+        val connectionTimeoutMillis: Int?,
+        val maxConnections: Int
     )
 
-
     override fun materialize() = object : CacheHandlerFactory {
-        private val client = MemcacheClient(this@MemcacheCacheConfiguration.servers, chunkSize)
-        override fun close() {
-            client.close()
+
+        private val connectionPoolMap = ConcurrentHashMap<HostAndPort, FixedChannelPool>()
+
+        override fun newHandler(
+            eventLoop: EventLoopGroup,
+            socketChannelFactory: ChannelFactory<SocketChannel>,
+            datagramChannelFactory: ChannelFactory<DatagramChannel>
+        ): ChannelHandler {
+            return MemcacheCacheHandler(
+                MemcacheClient(
+                    this@MemcacheCacheConfiguration.servers,
+                    chunkSize,
+                    eventLoop,
+                    socketChannelFactory,
+                    connectionPoolMap
+                ),
+                digestAlgorithm,
+                compressionMode != null,
+                compressionLevel,
+                chunkSize,
+                maxAge
+            )
+        }
+
+        override fun asyncClose() = object : CompletableFuture<Void>() {
+            init {
+                val failure = AtomicReference<Throwable>(null)
+                val pools = connectionPoolMap.values.toList()
+                val npools = pools.size
+                val finished = AtomicInteger(0)
+                pools.forEach { pool ->
+                    pool.closeAsync().addListener {
+                        if (!it.isSuccess) {
+                            failure.compareAndSet(null, it.cause())
+                        }
+                        if(finished.incrementAndGet() == npools) {
+                            when(val ex = failure.get()) {
+                                null -> complete(null)
+                                else -> completeExceptionally(ex)
+                            }
+                        }
+                    }
+                }
+            }
         }
 
-        override fun newHandler() = MemcacheCacheHandler(client, digestAlgorithm, compressionMode != null, compressionLevel, chunkSize, maxAge)
     }
 
     override fun getNamespaceURI() = "urn:net.woggioni.rbcs.server.memcache"

rbcs-server-memcache/src/main/kotlin/net/woggioni/rbcs/server/memcache/client/MemcacheClient.kt

@@ -4,16 +4,17 @@ package net.woggioni.rbcs.server.memcache.client
 import io.netty.bootstrap.Bootstrap
 import io.netty.buffer.ByteBuf
 import io.netty.channel.Channel
+import io.netty.channel.ChannelFactory
 import io.netty.channel.ChannelFutureListener
 import io.netty.channel.ChannelHandlerContext
 import io.netty.channel.ChannelOption
 import io.netty.channel.ChannelPipeline
+import io.netty.channel.EventLoopGroup
 import io.netty.channel.SimpleChannelInboundHandler
-import io.netty.channel.nio.NioEventLoopGroup
 import io.netty.channel.pool.AbstractChannelPoolHandler
 import io.netty.channel.pool.ChannelPool
 import io.netty.channel.pool.FixedChannelPool
-import io.netty.channel.socket.nio.NioSocketChannel
+import io.netty.channel.socket.SocketChannel
 import io.netty.handler.codec.memcache.LastMemcacheContent
 import io.netty.handler.codec.memcache.MemcacheContent
 import io.netty.handler.codec.memcache.MemcacheObject
@@ -33,23 +34,22 @@ import java.util.concurrent.ConcurrentHashMap
 import io.netty.util.concurrent.Future as NettyFuture
 
 
-class MemcacheClient(private val servers: List<MemcacheCacheConfiguration.Server>, private val chunkSize : Int) : AutoCloseable {
+class MemcacheClient(
+    private val servers: List<MemcacheCacheConfiguration.Server>,
+    private val chunkSize : Int,
+    private val group: EventLoopGroup,
+    private val channelFactory: ChannelFactory<SocketChannel>,
+    private val connectionPool: ConcurrentHashMap<HostAndPort, FixedChannelPool>
+) : AutoCloseable {
 
     private companion object {
         private val log = createLogger<MemcacheCacheHandler>()
     }
 
-    private val group: NioEventLoopGroup
-    private val connectionPool: MutableMap<HostAndPort, ChannelPool> = ConcurrentHashMap()
-
-    init {
-        group = NioEventLoopGroup()
-    }
-
     private fun newConnectionPool(server: MemcacheCacheConfiguration.Server): FixedChannelPool {
         val bootstrap = Bootstrap().apply {
             group(group)
-            channel(NioSocketChannel::class.java)
+            channelFactory(channelFactory)
             option(ChannelOption.SO_KEEPALIVE, true)
             remoteAddress(InetSocketAddress(server.endpoint.host, server.endpoint.port))
             server.connectionTimeoutMillis?.let {

rbcs-server-memcache/src/main/resources/net/woggioni/rbcs/server/memcache/schema/rbcs-memcache.xsd

@@ -21,7 +21,7 @@
                 </xs:sequence>
                 <xs:attribute name="max-age" type="xs:duration" default="P1D"/>
                 <xs:attribute name="chunk-size" type="rbcs:byteSizeType" default="0x10000"/>
-                <xs:attribute name="digest" type="xs:token" />
+                <xs:attribute name="digest" type="xs:token"/>
                 <xs:attribute name="compression-mode" type="rbcs-memcache:compressionType"/>
                 <xs:attribute name="compression-level" type="rbcs:compressionLevelType" default="-1"/>
             </xs:extension>

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/RemoteBuildCacheServer.kt

@@ -3,6 +3,7 @@ package net.woggioni.rbcs.server
 import io.netty.bootstrap.ServerBootstrap
 import io.netty.buffer.ByteBuf
 import io.netty.channel.Channel
+import io.netty.channel.ChannelFactory
 import io.netty.channel.ChannelFuture
 import io.netty.channel.ChannelHandler.Sharable
 import io.netty.channel.ChannelHandlerContext
@@ -11,7 +12,12 @@ import io.netty.channel.ChannelInitializer
 import io.netty.channel.ChannelOption
 import io.netty.channel.ChannelPromise
 import io.netty.channel.nio.NioEventLoopGroup
+import io.netty.channel.socket.DatagramChannel
+import io.netty.channel.socket.ServerSocketChannel
+import io.netty.channel.socket.SocketChannel
+import io.netty.channel.socket.nio.NioDatagramChannel
 import io.netty.channel.socket.nio.NioServerSocketChannel
+import io.netty.channel.socket.nio.NioSocketChannel
 import io.netty.handler.codec.compression.CompressionOptions
 import io.netty.handler.codec.http.DefaultHttpContent
 import io.netty.handler.codec.http.HttpContentCompressor
@@ -31,6 +37,7 @@ import io.netty.util.concurrent.DefaultEventExecutorGroup
 import io.netty.util.concurrent.EventExecutorGroup
 import net.woggioni.jwo.JWO
 import net.woggioni.jwo.Tuple2
+import net.woggioni.rbcs.api.AsyncCloseable
 import net.woggioni.rbcs.api.Configuration
 import net.woggioni.rbcs.api.exception.ConfigurationException
 import net.woggioni.rbcs.common.PasswordSecurity.decodePasswordHash
@@ -200,8 +207,10 @@ class RemoteBuildCacheServer(private val cfg: Configuration) {
 
     private class ServerInitializer(
         private val cfg: Configuration,
+        private val channelFactory : ChannelFactory<SocketChannel>,
+        private val datagramChannelFactory : ChannelFactory<DatagramChannel>,
         private val eventExecutorGroup: EventExecutorGroup
-    ) : ChannelInitializer<Channel>(), AutoCloseable {
+    ) : ChannelInitializer<Channel>(), AsyncCloseable {
 
         companion object {
             private fun createSslCtx(tls: Configuration.Tls): SslContext {
@@ -368,21 +377,20 @@ class RemoteBuildCacheServer(private val cfg: Configuration) {
                 ServerHandler(prefix)
             }
             pipeline.addLast(eventExecutorGroup, ServerHandler.NAME, serverHandler)
-            pipeline.addLast(cacheHandlerFactory.newHandler())
+
+            pipeline.addLast(cacheHandlerFactory.newHandler(ch.eventLoop(), channelFactory, datagramChannelFactory))
             pipeline.addLast(TraceHandler)
             pipeline.addLast(ExceptionHandler)
         }
 
-        override fun close() {
-            cacheHandlerFactory.close()
-        }
+        override fun asyncClose() = cacheHandlerFactory.asyncClose()
     }
 
     class ServerHandle(
         closeFuture: ChannelFuture,
         private val bossGroup: EventExecutorGroup,
         private val executorGroups: Iterable<EventExecutorGroup>,
-        private val serverInitializer: AutoCloseable,
+        private val serverInitializer: AsyncCloseable,
     ) : Future<Void> by from(closeFuture, executorGroups, serverInitializer) {
 
         companion object {
@@ -391,13 +399,28 @@ class RemoteBuildCacheServer(private val cfg: Configuration) {
             private fun from(
                 closeFuture: ChannelFuture,
                 executorGroups: Iterable<EventExecutorGroup>,
-                serverInitializer: AutoCloseable
+                serverInitializer: AsyncCloseable
             ): CompletableFuture<Void> {
                 val result = CompletableFuture<Void>()
                 closeFuture.addListener {
                     val errors = mutableListOf<Throwable>()
                     val deadline = Instant.now().plusSeconds(20)
+                    try {
+                        serverInitializer.close()
+                    } catch (ex: Throwable) {
+                        log.error(ex.message, ex)
+                        errors.addLast(ex)
+                    }
 
+                    serverInitializer.asyncClose().whenComplete { _, ex ->
+                        if(ex != null) {
+                            log.error(ex.message, ex)
+                            errors.addLast(ex)
+                        }
+
+                        executorGroups.map {
+                            it.shutdownGracefully()
+                        }
 
                         for (executorGroup in executorGroups) {
                             val future = executorGroup.terminationFuture()
@@ -417,18 +440,14 @@ class RemoteBuildCacheServer(private val cfg: Configuration) {
                                 errors.addLast(ex)
                             }
                         }
-                    try {
-                        serverInitializer.close()
-                    } catch (ex: Throwable) {
-                        log.error(ex.message, ex)
-                        errors.addLast(ex)
-                    }
+
                         if(errors.isEmpty()) {
                             result.complete(null)
                         } else {
                             result.completeExceptionally(errors.first())
                         }
                     }
+                }
 
                 return result.thenAccept {
                     log.info {
@@ -441,16 +460,15 @@ class RemoteBuildCacheServer(private val cfg: Configuration) {
 
         fun sendShutdownSignal() {
             bossGroup.shutdownGracefully()
-            executorGroups.map {
-                it.shutdownGracefully()
-            }
         }
     }
 
     fun run(): ServerHandle {
         // Create the multithreaded event loops for the server
         val bossGroup = NioEventLoopGroup(1)
-        val serverSocketChannel = NioServerSocketChannel::class.java
+        val channelFactory = ChannelFactory<SocketChannel> { NioSocketChannel() }
+        val datagramChannelFactory = ChannelFactory<DatagramChannel> { NioDatagramChannel() }
+        val serverChannelFactory = ChannelFactory<ServerSocketChannel> { NioServerSocketChannel() }
         val workerGroup = NioEventLoopGroup(0)
         val eventExecutorGroup = run {
             val threadFactory = if (cfg.eventExecutor.isUseVirtualThreads) {
@@ -460,11 +478,11 @@ class RemoteBuildCacheServer(private val cfg: Configuration) {
             }
             DefaultEventExecutorGroup(Runtime.getRuntime().availableProcessors(), threadFactory)
         }
-        val serverInitializer = ServerInitializer(cfg, eventExecutorGroup)
+        val serverInitializer = ServerInitializer(cfg, channelFactory, datagramChannelFactory, workerGroup)
         val bootstrap = ServerBootstrap().apply {
             // Configure the server
             group(bossGroup, workerGroup)
-            channel(serverSocketChannel)
+            channelFactory(serverChannelFactory)
             childHandler(serverInitializer)
             option(ChannelOption.SO_BACKLOG, cfg.incomingConnectionsBacklogSize)
             childOption(ChannelOption.SO_KEEPALIVE, true)

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/cache/FileSystemCache.kt

@@ -1,6 +1,7 @@
 package net.woggioni.rbcs.server.cache
 
 import net.woggioni.jwo.JWO
+import net.woggioni.rbcs.api.AsyncCloseable
 import net.woggioni.rbcs.api.CacheValueMetadata
 import net.woggioni.rbcs.common.createLogger
 import java.io.ByteArrayOutputStream
@@ -18,11 +19,12 @@ import java.nio.file.StandardOpenOption
 import java.nio.file.attribute.BasicFileAttributes
 import java.time.Duration
 import java.time.Instant
+import java.util.concurrent.CompletableFuture
 
 class FileSystemCache(
     val root: Path,
     val maxAge: Duration
-) : AutoCloseable {
+) : AsyncCloseable {
 
     class EntryValue(val metadata: CacheValueMetadata, val channel : FileChannel, val offset : Long, val size : Long) : Serializable
 
@@ -112,10 +114,19 @@ class FileSystemCache(
         return FileSink(metadata, file, tmpFile)
     }
 
-    private val garbageCollector = Thread.ofVirtual().name("file-system-cache-gc").start {
+    private val closeFuture = object : CompletableFuture<Void>() {
+        init {
+            Thread.ofVirtual().name("file-system-cache-gc").start {
+                try {
                     while (running) {
                         gc()
                     }
+                    complete(null)
+                } catch (ex : Throwable) {
+                    completeExceptionally(ex)
+                }
+            }
+        }
     }
 
     private fun gc() {
@@ -151,8 +162,8 @@ class FileSystemCache(
         return result
     }
 
-    override fun close() {
+    override fun asyncClose() : CompletableFuture<Void> {
         running = false
-        garbageCollector.join()
+        return closeFuture
     }
 }

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/cache/FileSystemCacheConfiguration.kt

@@ -1,5 +1,9 @@
 package net.woggioni.rbcs.server.cache
 
+import io.netty.channel.ChannelFactory
+import io.netty.channel.EventLoopGroup
+import io.netty.channel.socket.DatagramChannel
+import io.netty.channel.socket.SocketChannel
 import net.woggioni.jwo.Application
 import net.woggioni.rbcs.api.CacheHandlerFactory
 import net.woggioni.rbcs.api.Configuration
@@ -19,11 +23,13 @@ data class FileSystemCacheConfiguration(
     override fun materialize() = object : CacheHandlerFactory {
         private val cache = FileSystemCache(root ?: Application.builder("rbcs").build().computeCacheDirectory(), maxAge)
 
-        override fun close() {
-            cache.close()
-        }
+        override fun asyncClose() = cache.asyncClose()
 
-        override fun newHandler() = FileSystemCacheHandler(cache, digestAlgorithm, compressionEnabled, compressionLevel, chunkSize)
+        override fun newHandler(
+            eventLoop: EventLoopGroup,
+            socketChannelFactory: ChannelFactory<SocketChannel>,
+            datagramChannelFactory: ChannelFactory<DatagramChannel>
+        ) = FileSystemCacheHandler(cache, digestAlgorithm, compressionEnabled, compressionLevel, chunkSize)
     }
 
     override fun getNamespaceURI() = RBCS.RBCS_NAMESPACE_URI

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/cache/FileSystemCacheProvider.kt

@@ -30,7 +30,7 @@ class FileSystemCacheProvider : CacheProvider<FileSystemCacheConfiguration> {
         val compressionLevel = el.renderAttribute("compression-level")
             ?.let(String::toInt)
             ?: Deflater.DEFAULT_COMPRESSION
-        val digestAlgorithm = el.renderAttribute("digest") ?: "MD5"
+        val digestAlgorithm = el.renderAttribute("digest")
         val chunkSize = el.renderAttribute("chunk-size")
             ?.let(Integer::decode)
             ?: 0x10000

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/cache/InMemoryCache.kt

@@ -1,10 +1,12 @@
 package net.woggioni.rbcs.server.cache
 
 import io.netty.buffer.ByteBuf
+import net.woggioni.rbcs.api.AsyncCloseable
 import net.woggioni.rbcs.api.CacheValueMetadata
 import net.woggioni.rbcs.common.createLogger
 import java.time.Duration
 import java.time.Instant
+import java.util.concurrent.CompletableFuture
 import java.util.concurrent.ConcurrentHashMap
 import java.util.concurrent.PriorityBlockingQueue
 import java.util.concurrent.TimeUnit
@@ -26,7 +28,7 @@ class CacheEntry(
 class InMemoryCache(
     private val maxAge: Duration,
     private val maxSize: Long
-) : AutoCloseable {
+) : AsyncCloseable {
 
     companion object {
         private val log = createLogger<InMemoryCache>()
@@ -45,7 +47,10 @@ class InMemoryCache(
     @Volatile
     private var running = true
 
-    private val garbageCollector = Thread.ofVirtual().name("in-memory-cache-gc").start {
+    private val closeFuture = object : CompletableFuture<Void>() {
+        init {
+            Thread.ofVirtual().name("in-memory-cache-gc").start {
+                try {
                     while (running) {
                         val el = removalQueue.poll(1, TimeUnit.SECONDS) ?: continue
                         val value = el.value
@@ -62,9 +67,15 @@ class InMemoryCache(
                             Thread.sleep(minOf(Duration.between(now, el.expiry), Duration.ofSeconds(1)))
                         }
                     }
+                    complete(null)
+                } catch (ex: Throwable) {
+                    completeExceptionally(ex)
+                }
+            }
+        }
     }
 
-    private fun removeEldest(): Long {
+    fun removeEldest(): Long {
         while (true) {
             val el = removalQueue.take()
             val value = el.value
@@ -84,9 +95,9 @@ class InMemoryCache(
         }
     }
 
-    override fun close() {
+    override fun asyncClose() : CompletableFuture<Void> {
         running = false
-        garbageCollector.join()
+        return closeFuture
     }
 
     fun get(key: ByteArray) = map[CacheKey(key)]?.run {

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/cache/InMemoryCacheConfiguration.kt

@@ -1,5 +1,10 @@
 package net.woggioni.rbcs.server.cache
 
+import io.netty.channel.ChannelFactory
+import io.netty.channel.EventLoopGroup
+import io.netty.channel.socket.DatagramChannel
+import io.netty.channel.socket.SocketChannel
+import io.netty.util.concurrent.Future
 import net.woggioni.rbcs.api.CacheHandlerFactory
 import net.woggioni.rbcs.api.Configuration
 import net.woggioni.rbcs.common.RBCS
@@ -16,11 +21,13 @@ data class InMemoryCacheConfiguration(
     override fun materialize() = object : CacheHandlerFactory {
         private val cache = InMemoryCache(maxAge, maxSize)
 
-        override fun close() {
-            cache.close()
-        }
+        override fun asyncClose() = cache.asyncClose()
 
-        override fun newHandler() = InMemoryCacheHandler(cache, digestAlgorithm, compressionEnabled, compressionLevel)
+        override fun newHandler(
+            eventLoop: EventLoopGroup,
+            socketChannelFactory: ChannelFactory<SocketChannel>,
+            datagramChannelFactory: ChannelFactory<DatagramChannel>
+        ) = InMemoryCacheHandler(cache, digestAlgorithm, compressionEnabled, compressionLevel)
     }
 
     override fun getNamespaceURI() = RBCS.RBCS_NAMESPACE_URI

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/cache/InMemoryCacheProvider.kt

@@ -30,7 +30,7 @@ class InMemoryCacheProvider : CacheProvider<InMemoryCacheConfiguration> {
         val compressionLevel = el.renderAttribute("compression-level")
             ?.let(String::toInt)
             ?: Deflater.DEFAULT_COMPRESSION
-        val digestAlgorithm = el.renderAttribute("digest") ?: "MD5"
+        val digestAlgorithm = el.renderAttribute("digest")
         val chunkSize = el.renderAttribute("chunk-size")
             ?.let(Integer::decode)
             ?: 0x10000

rbcs-server/src/main/resources/net/woggioni/rbcs/server/schema/rbcs.xsd

@@ -153,7 +153,7 @@
                         </xs:documentation>
                     </xs:annotation>
                 </xs:attribute>
-                <xs:attribute name="digest" type="xs:token" default="MD5">
+                <xs:attribute name="digest" type="xs:token">
                     <xs:annotation>
                         <xs:documentation>
                             Hashing algorithm to apply to the key. If omitted, no hashing is performed.
@@ -209,7 +209,7 @@
                         </xs:documentation>
                     </xs:annotation>
                 </xs:attribute>
-                <xs:attribute name="digest" type="xs:token" default="MD5">
+                <xs:attribute name="digest" type="xs:token" default="SHA3-224">
                     <xs:annotation>
                         <xs:documentation>
                             Hashing algorithm to apply to the key. If omitted, no hashing is performed.