fixed server support for request pipelining

rbcs-api/build.gradle

@@ -5,9 +5,12 @@ plugins {
 }
 
 dependencies {
+    implementation catalog.slf4j.api
+    implementation project(':rbcs-common')
     api catalog.netty.common
     api catalog.netty.buffer
     api catalog.netty.handler
+    api catalog.netty.codec.http
 }
 
 publishing {

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

@@ -1,10 +1,15 @@
 module net.woggioni.rbcs.api {
     requires static lombok;
-    requires java.xml;
-    requires io.netty.buffer;
     requires io.netty.handler;
-    requires io.netty.transport;
     requires io.netty.common;
+    requires net.woggioni.rbcs.common;
+    requires io.netty.transport;
+    requires io.netty.codec.http;
+    requires io.netty.buffer;
+    requires org.slf4j;
+    requires java.xml;
+
+
     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/CacheHandler.java

@@ -0,0 +1,57 @@
+package net.woggioni.rbcs.api;
+
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelInboundHandlerAdapter;
+import io.netty.handler.codec.http.LastHttpContent;
+import io.netty.util.ReferenceCounted;
+import lombok.extern.slf4j.Slf4j;
+import net.woggioni.rbcs.api.message.CacheMessage;
+
+@Slf4j
+public abstract class CacheHandler extends ChannelInboundHandlerAdapter {
+    private boolean requestFinished = false;
+
+    abstract protected void channelRead0(ChannelHandlerContext ctx, CacheMessage msg);
+
+    @Override
+    public void channelRead(ChannelHandlerContext ctx, Object msg) {
+        if(!requestFinished && msg instanceof CacheMessage) {
+            if(msg instanceof CacheMessage.LastCacheContent || msg instanceof CacheMessage.CacheGetRequest) requestFinished = true;
+            try {
+                channelRead0(ctx, (CacheMessage) msg);
+            } finally {
+                if(msg instanceof ReferenceCounted rc) rc.release();
+            }
+        } else {
+            ctx.fireChannelRead(msg);
+        }
+    }
+
+    protected void sendMessageAndFlush(ChannelHandlerContext ctx, Object msg) {
+        sendMessage(ctx, msg, true);
+    }
+
+    protected void sendMessage(ChannelHandlerContext ctx, Object msg) {
+        sendMessage(ctx, msg, false);
+    }
+
+    private void sendMessage(ChannelHandlerContext ctx, Object msg, boolean flush) {
+        ctx.write(msg);
+        if(
+                msg instanceof CacheMessage.LastCacheContent ||
+                msg instanceof CacheMessage.CachePutResponse ||
+                msg instanceof CacheMessage.CacheValueNotFoundResponse ||
+                msg instanceof LastHttpContent
+        ) {
+            ctx.flush();
+            ctx.pipeline().remove(this);
+        } else if(flush) {
+            ctx.flush();
+        }
+    }
+
+    @Override
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+        super.exceptionCaught(ctx, cause);
+    }
+}

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

@@ -1,13 +1,12 @@
 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 AsyncCloseable {
-    ChannelHandler newHandler(
+    CacheHandler newHandler(
             Configuration configuration,
             EventLoopGroup eventLoopGroup,
             ChannelFactory<SocketChannel> socketChannelFactory,

rbcs-client/src/main/kotlin/net/woggioni/rbcs/client/Configuration.kt

@@ -38,11 +38,12 @@ data class Configuration(
         val readIdleTimeout: Duration,
         val writeIdleTimeout: Duration,
         val idleTimeout: Duration,
+        val requestPipelining : Boolean,
     )
 
     data class Profile(
         val serverURI: URI,
-        val connection: Connection?,
+        val connection: Connection,
         val authentication: Authentication?,
         val connectionTimeout: Duration?,
         val maxConnections: Int,

rbcs-client/src/main/kotlin/net/woggioni/rbcs/client/RemoteBuildCacheClient.kt

@@ -318,6 +318,9 @@ class RemoteBuildCacheClient(private val profile: Configuration.Profile) : AutoC
                         ) {
                             pipeline.remove(this)
                             responseFuture.complete(response)
+                            if(!profile.connection.requestPipelining) {
+                                pool.release(channel)
+                            }
                         }
 
                         override fun exceptionCaught(ctx: ChannelHandlerContext, cause: Throwable) {
@@ -332,6 +335,9 @@ class RemoteBuildCacheClient(private val profile: Configuration.Profile) : AutoC
 
                         override fun channelInactive(ctx: ChannelHandlerContext) {
                             responseFuture.completeExceptionally(IOException("The remote server closed the connection"))
+                            if(!profile.connection.requestPipelining) {
+                                pool.release(channel)
+                            }
                             super.channelInactive(ctx)
                         }
 
@@ -352,6 +358,9 @@ class RemoteBuildCacheClient(private val profile: Configuration.Profile) : AutoC
                                 if (this === pipeline.last()) {
                                     ctx.close()
                                 }
+                                if(!profile.connection.requestPipelining) {
+                                    pool.release(channel)
+                                }
                             } else {
                                 super.userEventTriggered(ctx, evt)
                             }
@@ -401,8 +410,9 @@ class RemoteBuildCacheClient(private val profile: Configuration.Profile) : AutoC
                             val ex = it.cause()
                             log.warn(ex.message, ex)
                         }
-
+                        if(profile.connection.requestPipelining) {
-                        pool.release(channel)
+                            pool.release(channel)
+                        }
                     }
                 } else {
                     responseFuture.completeExceptionally(channelFuture.cause())

rbcs-client/src/main/kotlin/net/woggioni/rbcs/client/impl/Parser.kt

@@ -30,7 +30,12 @@ object Parser {
                         ?: throw ConfigurationException("base-url attribute is required")
                     var authentication: Configuration.Authentication? = null
                     var retryPolicy: Configuration.RetryPolicy? = null
-                    var connection : Configuration.Connection? = null
+                    var connection : Configuration.Connection = Configuration.Connection(
+                        Duration.ofSeconds(60),
+                        Duration.ofSeconds(60),
+                        Duration.ofSeconds(30),
+                        false
+                    )
                     var trustStore : Configuration.TrustStore? = null
                     for (gchild in child.asIterable()) {
                         when (gchild.localName) {
@@ -97,10 +102,13 @@ object Parser {
                                     ?.let(Duration::parse) ?: Duration.of(60, ChronoUnit.SECONDS)
                                 val writeIdleTimeout = gchild.renderAttribute("write-idle-timeout")
                                     ?.let(Duration::parse) ?: Duration.of(60, ChronoUnit.SECONDS)
+                                val requestPipelining = gchild.renderAttribute("request-pipelining")
+                                    ?.let(String::toBoolean) ?: false
                                 connection = Configuration.Connection(
                                     readIdleTimeout,
                                     writeIdleTimeout,
                                     idleTimeout,
+                                    requestPipelining
                                 )
                             }
 

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

@@ -123,6 +123,13 @@
                 </xs:documentation>
             </xs:annotation>
         </xs:attribute>
+        <xs:attribute name="request-pipelining" type="xs:boolean" use="optional" default="false">
+            <xs:annotation>
+                <xs:documentation>
+                    Enables HTTP/1.1 request pipelining
+                </xs:documentation>
+            </xs:annotation>
+        </xs:attribute>
     </xs:complexType>
 
     <xs:complexType name="noAuthType">

rbcs-common/build.gradle

@@ -6,7 +6,7 @@ plugins {
 }
 
 dependencies {
-    implementation project(':rbcs-api')
+    implementation catalog.netty.transport
     implementation catalog.slf4j.api
     implementation catalog.jwo
     implementation catalog.netty.buffer

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

@@ -6,6 +6,7 @@ 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.CacheHandler
 import net.woggioni.rbcs.api.CacheHandlerFactory
 import net.woggioni.rbcs.api.Configuration
 import net.woggioni.rbcs.common.HostAndPort
@@ -51,7 +52,7 @@ data class MemcacheCacheConfiguration(
             eventLoop: EventLoopGroup,
             socketChannelFactory: ChannelFactory<SocketChannel>,
             datagramChannelFactory: ChannelFactory<DatagramChannel>,
-        ): ChannelHandler {
+        ): CacheHandler {
             return MemcacheCacheHandler(
                 MemcacheClient(
                     this@MemcacheCacheConfiguration.servers,

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

@@ -4,7 +4,6 @@ import io.netty.buffer.ByteBuf
 import io.netty.buffer.ByteBufAllocator
 import io.netty.buffer.CompositeByteBuf
 import io.netty.channel.ChannelHandlerContext
-import io.netty.channel.SimpleChannelInboundHandler
 import io.netty.handler.codec.memcache.DefaultLastMemcacheContent
 import io.netty.handler.codec.memcache.DefaultMemcacheContent
 import io.netty.handler.codec.memcache.LastMemcacheContent
@@ -13,6 +12,7 @@ import io.netty.handler.codec.memcache.binary.BinaryMemcacheOpcodes
 import io.netty.handler.codec.memcache.binary.BinaryMemcacheResponse
 import io.netty.handler.codec.memcache.binary.BinaryMemcacheResponseStatus
 import io.netty.handler.codec.memcache.binary.DefaultBinaryMemcacheRequest
+import net.woggioni.rbcs.api.CacheHandler
 import net.woggioni.rbcs.api.CacheValueMetadata
 import net.woggioni.rbcs.api.exception.ContentTooLargeException
 import net.woggioni.rbcs.api.message.CacheMessage
@@ -58,7 +58,7 @@ class MemcacheCacheHandler(
     private val compressionLevel: Int,
     private val chunkSize: Int,
     private val maxAge: Duration
-) : SimpleChannelInboundHandler<CacheMessage>() {
+) : CacheHandler() {
     companion object {
         private val log = createLogger<MemcacheCacheHandler>()
 
@@ -98,7 +98,10 @@ class MemcacheCacheHandler(
                         acc.retain()
                         it.readObject() as CacheValueMetadata
                     }
-                    ctx.writeAndFlush(CacheValueFoundResponse(key, metadata))
+                    log.trace(ctx) {
+                        "Sending response from cache"
+                    }
+                    sendMessageAndFlush(ctx, CacheValueFoundResponse(key, metadata))
                     responseSent = true
                     acc.readerIndex(Int.SIZE_BYTES + mSize)
                 }
@@ -114,16 +117,16 @@ class MemcacheCacheHandler(
             val toSend = extractChunk(chunk, ctx.alloc())
             val msg = if(last) {
                 log.trace(ctx) {
-                    "Sending last chunk to client on channel ${ctx.channel().id().asShortText()}"
+                    "Sending last chunk to client on channel"
                 }
                 LastCacheContent(toSend)
             } else {
                 log.trace(ctx) {
-                    "Sending chunk to client on channel ${ctx.channel().id().asShortText()}"
+                    "Sending chunk to client"
                 }
                 CacheContent(toSend)
             }
-            ctx.writeAndFlush(msg)
+            sendMessageAndFlush(ctx, msg)
         }
 
         fun commit() {
@@ -259,7 +262,7 @@ class MemcacheCacheHandler(
                         log.debug(ctx) {
                             "Cache miss for key ${msg.key} on memcache"
                         }
-                        ctx.writeAndFlush(CacheValueNotFoundResponse())
+                        sendMessageAndFlush(ctx, CacheValueNotFoundResponse())
                     }
                 }
             }
@@ -290,6 +293,7 @@ class MemcacheCacheHandler(
                 setOpcode(BinaryMemcacheOpcodes.GET)
             }
             requestHandle.sendRequest(request)
+            requestHandle.sendContent(LastMemcacheContent.EMPTY_LAST_CONTENT)
         }
     }
 
@@ -305,7 +309,7 @@ class MemcacheCacheHandler(
                         log.debug(ctx) {
                             "Inserted key ${msg.key} into memcache"
                         }
-                        ctx.writeAndFlush(CachePutResponse(msg.key))
+                        sendMessageAndFlush(ctx, CachePutResponse(msg.key))
                     }
                     else -> this@MemcacheCacheHandler.exceptionCaught(ctx, MemcacheException(status))
                 }
@@ -348,6 +352,9 @@ class MemcacheCacheHandler(
             extras.writeInt(0)
             extras.writeInt(encodeExpiry(maxAge))
             val totalBodyLength = request.digest.readableBytes() + extras.readableBytes() + payloadSize
+            log.trace(ctx) {
+                "Trying to send SET request to memcache"
+            }
             request.requestController.whenComplete { requestController, ex ->
                 if(ex == null) {
                     log.trace(ctx) {

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

@@ -12,7 +12,6 @@ import io.netty.channel.ChannelPipeline
 import io.netty.channel.EventLoopGroup
 import io.netty.channel.SimpleChannelInboundHandler
 import io.netty.channel.pool.AbstractChannelPoolHandler
-import io.netty.channel.pool.ChannelPool
 import io.netty.channel.pool.FixedChannelPool
 import io.netty.channel.socket.SocketChannel
 import io.netty.handler.codec.memcache.LastMemcacheContent
@@ -24,7 +23,7 @@ import io.netty.handler.codec.memcache.binary.BinaryMemcacheResponse
 import io.netty.util.concurrent.GenericFutureListener
 import net.woggioni.rbcs.common.HostAndPort
 import net.woggioni.rbcs.common.createLogger
-import net.woggioni.rbcs.common.warn
+import net.woggioni.rbcs.common.trace
 import net.woggioni.rbcs.server.memcache.MemcacheCacheConfiguration
 import net.woggioni.rbcs.server.memcache.MemcacheCacheHandler
 import java.io.IOException
@@ -94,18 +93,6 @@ class MemcacheClient(
         pool.acquire().addListener(object : GenericFutureListener<NettyFuture<Channel>> {
             override fun operationComplete(channelFuture: NettyFuture<Channel>) {
                 if (channelFuture.isSuccess) {
-
-                    var requestSent = false
-                    var requestBodySent = false
-                    var requestFinished = false
-                    var responseReceived = false
-                    var responseBodyReceived = false
-                    var responseFinished = false
-                    var requestBodySize = 0
-                    var requestBodyBytesSent = 0
-
-
-
                     val channel = channelFuture.now
                     var connectionClosedByTheRemoteServer = true
                     val closeCallback = {
@@ -113,14 +100,7 @@ class MemcacheClient(
                             val ex = IOException("The memcache server closed the connection")
                             val completed = response.completeExceptionally(ex)
                             if(!completed) responseHandler.exceptionCaught(ex)
-                            log.warn {
-                                "RequestSent: $requestSent, RequestBodySent: $requestBodySent, " +
-                                "RequestFinished: $requestFinished, ResponseReceived: $responseReceived, " +
-                                "ResponseBodyReceived: $responseBodyReceived, ResponseFinished: $responseFinished, " +
-                                "RequestBodySize: $requestBodySize, RequestBodyBytesSent: $requestBodyBytesSent"
-                            }
                         }
-                        pool.release(channel)
                     }
                     val closeListener = ChannelFutureListener {
                         closeCallback()
@@ -140,18 +120,14 @@ class MemcacheClient(
                             when (msg) {
                                 is BinaryMemcacheResponse -> {
                                     responseHandler.responseReceived(msg)
-                                    responseReceived = true
                                 }
 
                                 is LastMemcacheContent -> {
-                                    responseFinished = true
                                     responseHandler.contentReceived(msg)
                                     pipeline.remove(this)
-                                    pool.release(channel)
                                 }
 
                                 is MemcacheContent -> {
-                                    responseBodyReceived = true
                                     responseHandler.contentReceived(msg)
                                 }
                             }
@@ -165,35 +141,43 @@ class MemcacheClient(
                         override fun exceptionCaught(ctx: ChannelHandlerContext, cause: Throwable) {
                             connectionClosedByTheRemoteServer = false
                             ctx.close()
-                            pool.release(channel)
                             responseHandler.exceptionCaught(cause)
                         }
                     }
 
-                    channel.pipeline()
+                    channel.pipeline().addLast(handler)
-                        .addLast("client-handler", handler)
                     response.complete(object : MemcacheRequestController {
+                        private var channelReleased = false
 
                         override fun sendRequest(request: BinaryMemcacheRequest) {
-                            requestBodySize = request.totalBodyLength() - request.keyLength() - request.extrasLength()
                             channel.writeAndFlush(request)
-                            requestSent = true
                         }
 
                         override fun sendContent(content: MemcacheContent) {
-                            val size = content.content().readableBytes()
                             channel.writeAndFlush(content).addListener {
-                                requestBodyBytesSent += size
-                                requestBodySent = true
                                 if(content is LastMemcacheContent) {
-                                    requestFinished = true
+                                    if(!channelReleased) {
+                                        pool.release(channel)
+                                        channelReleased = true
+                                        log.trace(channel) {
+                                            "Channel released"
+                                        }
+                                    }
                                 }
                             }
                         }
 
                         override fun exceptionCaught(ex: Throwable) {
+                            log.warn(ex.message, ex)
                             connectionClosedByTheRemoteServer = false
                             channel.close()
+                            if(!channelReleased) {
+                                pool.release(channel)
+                                channelReleased = true
+                                log.trace(channel) {
+                                    "Channel released"
+                                }
+                            }
                         }
                     })
                 } else {

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

@@ -298,6 +298,7 @@ class RemoteBuildCacheServer(private val cfg: Configuration) {
                     "Closed connection ${ch.id().asShortText()} with ${ch.remoteAddress()}"
                 }
             }
+            ch.config().setAutoRead(false)
             val pipeline = ch.pipeline()
             cfg.connection.also { conn ->
                 val readIdleTimeout = conn.readIdleTimeout.toMillis()

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

@@ -5,6 +5,7 @@ import io.netty.channel.ChannelHandlerContext
 import io.netty.channel.SimpleChannelInboundHandler
 import io.netty.handler.codec.http.LastHttpContent
 import io.netty.handler.stream.ChunkedNioFile
+import net.woggioni.rbcs.api.CacheHandler
 import net.woggioni.rbcs.api.message.CacheMessage
 import net.woggioni.rbcs.api.message.CacheMessage.CacheContent
 import net.woggioni.rbcs.api.message.CacheMessage.CacheGetRequest
@@ -26,7 +27,7 @@ class FileSystemCacheHandler(
     private val compressionEnabled: Boolean,
     private val compressionLevel: Int,
     private val chunkSize: Int
-) : SimpleChannelInboundHandler<CacheMessage>() {
+) : CacheHandler() {
 
     private inner class InProgressPutRequest(
         val key : String,
@@ -70,7 +71,7 @@ class FileSystemCacheHandler(
     private fun handleGetRequest(ctx: ChannelHandlerContext, msg: CacheGetRequest) {
         val key = String(Base64.getUrlEncoder().encode(processCacheKey(msg.key, digestAlgorithm)))
         cache.get(key)?.also { entryValue ->
-            ctx.writeAndFlush(CacheValueFoundResponse(msg.key, entryValue.metadata))
+            sendMessageAndFlush(ctx, CacheValueFoundResponse(msg.key, entryValue.metadata))
             entryValue.channel.let { channel ->
                 if(compressionEnabled) {
                     InflaterInputStream(Channels.newInputStream(channel)).use { stream ->
@@ -81,19 +82,19 @@ class FileSystemCacheHandler(
                             while(buf.readableBytes() < chunkSize) {
                                 val read = buf.writeBytes(stream, chunkSize)
                                 if(read < 0) {
-                                    ctx.writeAndFlush(LastCacheContent(buf))
+                                    sendMessageAndFlush(ctx, LastCacheContent(buf))
                                     break@outerLoop
                                 }
                             }
-                            ctx.writeAndFlush(CacheContent(buf))
+                            sendMessageAndFlush(ctx, CacheContent(buf))
                         }
                     }
                 } else {
-                    ctx.writeAndFlush(ChunkedNioFile(channel, entryValue.offset, entryValue.size - entryValue.offset, chunkSize))
+                    sendMessage(ctx, ChunkedNioFile(channel, entryValue.offset, entryValue.size - entryValue.offset, chunkSize))
-                    ctx.writeAndFlush(LastHttpContent.EMPTY_LAST_CONTENT)
+                    sendMessageAndFlush(ctx, LastHttpContent.EMPTY_LAST_CONTENT)
                 }
             }
-        } ?: ctx.writeAndFlush(CacheValueNotFoundResponse())
+        } ?: sendMessageAndFlush(ctx, CacheValueNotFoundResponse())
     }
 
     private fun handlePutRequest(ctx: ChannelHandlerContext, msg: CachePutRequest) {
@@ -111,7 +112,7 @@ class FileSystemCacheHandler(
             inProgressPutRequest = null
             request.write(msg.content())
             request.commit()
-            ctx.writeAndFlush(CachePutResponse(request.key))
+            sendMessageAndFlush(ctx, CachePutResponse(request.key))
         }
     }
 

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

@@ -3,6 +3,7 @@ package net.woggioni.rbcs.server.cache
 import io.netty.buffer.ByteBuf
 import io.netty.channel.ChannelHandlerContext
 import io.netty.channel.SimpleChannelInboundHandler
+import net.woggioni.rbcs.api.CacheHandler
 import net.woggioni.rbcs.api.message.CacheMessage
 import net.woggioni.rbcs.api.message.CacheMessage.CacheContent
 import net.woggioni.rbcs.api.message.CacheMessage.CacheGetRequest
@@ -13,6 +14,7 @@ import net.woggioni.rbcs.api.message.CacheMessage.CacheValueNotFoundResponse
 import net.woggioni.rbcs.api.message.CacheMessage.LastCacheContent
 import net.woggioni.rbcs.common.ByteBufOutputStream
 import net.woggioni.rbcs.common.RBCS.processCacheKey
+import net.woggioni.rbcs.common.trace
 import java.util.zip.Deflater
 import java.util.zip.DeflaterOutputStream
 import java.util.zip.InflaterOutputStream
@@ -22,7 +24,7 @@ class InMemoryCacheHandler(
     private val digestAlgorithm: String?,
     private val compressionEnabled: Boolean,
     private val compressionLevel: Int
-) : SimpleChannelInboundHandler<CacheMessage>() {
+) : CacheHandler() {
 
     private interface InProgressPutRequest : AutoCloseable {
         val request: CachePutRequest
@@ -86,7 +88,7 @@ class InMemoryCacheHandler(
 
     private fun handleGetRequest(ctx: ChannelHandlerContext, msg: CacheGetRequest) {
         cache.get(processCacheKey(msg.key, digestAlgorithm))?.let { value ->
-            ctx.writeAndFlush(CacheValueFoundResponse(msg.key, value.metadata))
+            sendMessageAndFlush(ctx, CacheValueFoundResponse(msg.key, value.metadata))
             if (compressionEnabled) {
                 val buf = ctx.alloc().heapBuffer()
                 InflaterOutputStream(ByteBufOutputStream(buf)).use {
@@ -94,11 +96,11 @@ class InMemoryCacheHandler(
                     value.content.release()
                     buf.retain()
                 }
-                ctx.writeAndFlush(LastCacheContent(buf))
+                sendMessage(ctx, LastCacheContent(buf))
             } else {
-                ctx.writeAndFlush(LastCacheContent(value.content))
+                sendMessage(ctx, LastCacheContent(value.content))
             }
-        } ?: ctx.writeAndFlush(CacheValueNotFoundResponse())
+        } ?: sendMessage(ctx, CacheValueNotFoundResponse())
     }
 
     private fun handlePutRequest(ctx: ChannelHandlerContext, msg: CachePutRequest) {
@@ -122,7 +124,7 @@ class InMemoryCacheHandler(
             inProgressRequest.close()
             val cacheKey = processCacheKey(inProgressRequest.request.key, digestAlgorithm)
             cache.put(cacheKey, CacheEntry(inProgressRequest.request.metadata, buf))
-            ctx.writeAndFlush(CachePutResponse(inProgressRequest.request.key))
+            sendMessageAndFlush(ctx, CachePutResponse(inProgressRequest.request.key))
         }
     }
 

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/event/RequestCompletedEvent.kt

@@ -1,4 +0,0 @@
-package net.woggioni.rbcs.server.event
-
-class RequestCompletedEvent {
-}

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/handler/CacheContentHandler.kt

@@ -1,79 +0,0 @@
-package net.woggioni.rbcs.server.handler
-
-import io.netty.channel.ChannelHandler
-import io.netty.channel.ChannelHandler.Sharable
-import io.netty.channel.ChannelHandlerContext
-import io.netty.channel.ChannelOutboundHandler
-import io.netty.channel.ChannelPromise
-import io.netty.channel.SimpleChannelInboundHandler
-import io.netty.handler.codec.http.HttpContent
-import io.netty.handler.codec.http.LastHttpContent
-import net.woggioni.rbcs.api.message.CacheMessage.CacheValueNotFoundResponse
-import net.woggioni.rbcs.api.message.CacheMessage.CacheContent
-import net.woggioni.rbcs.api.message.CacheMessage.CachePutResponse
-import net.woggioni.rbcs.api.message.CacheMessage.LastCacheContent
-import java.net.SocketAddress
-
-class CacheContentHandler(private val pairedHandler : ChannelHandler) : SimpleChannelInboundHandler<HttpContent>(), ChannelOutboundHandler {
-    private var requestFinished = false
-
-    override fun channelRead0(ctx: ChannelHandlerContext, msg: HttpContent) {
-        if(requestFinished) {
-            ctx.fireChannelRead(msg.retain())
-        } else {
-            when (msg) {
-                is LastHttpContent -> {
-                    ctx.fireChannelRead(LastCacheContent(msg.content().retain()))
-                    requestFinished = true
-                }
-                else -> ctx.fireChannelRead(CacheContent(msg.content().retain()))
-            }
-        }
-    }
-
-    override fun exceptionCaught(ctx: ChannelHandlerContext, cause: Throwable) {
-        super.exceptionCaught(ctx, cause)
-    }
-
-
-    override fun bind(ctx: ChannelHandlerContext, localAddress: SocketAddress, promise: ChannelPromise) {
-        ctx.bind(localAddress, promise)
-    }
-
-    override fun connect(
-        ctx: ChannelHandlerContext,
-        remoteAddress: SocketAddress,
-        localAddress: SocketAddress,
-        promise: ChannelPromise
-    ) {
-        ctx.connect(remoteAddress, localAddress, promise)
-    }
-
-    override fun disconnect(ctx: ChannelHandlerContext, promise: ChannelPromise) {
-        ctx.disconnect(promise)
-    }
-
-    override fun close(ctx: ChannelHandlerContext, promise: ChannelPromise) {
-        ctx.close(promise)
-    }
-
-    override fun deregister(ctx: ChannelHandlerContext, promise: ChannelPromise) {
-        ctx.deregister(promise)
-    }
-
-    override fun read(ctx: ChannelHandlerContext) {
-        ctx.read()
-    }
-
-    override fun flush(ctx: ChannelHandlerContext) {
-        ctx.flush()
-    }
-
-    override fun write(ctx: ChannelHandlerContext, msg: Any, promise: ChannelPromise) {
-        ctx.write(msg, promise)
-        if(msg is LastCacheContent || msg is CachePutResponse || msg is CacheValueNotFoundResponse || msg is LastHttpContent) {
-            ctx.pipeline().remove(pairedHandler)
-            ctx.pipeline().remove(this)
-        }
-    }
-}

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/handler/ResponseCapHandler.kt

@@ -1,56 +0,0 @@
-package net.woggioni.rbcs.server.handler
-
-import io.netty.channel.ChannelHandlerContext
-import io.netty.channel.ChannelInboundHandlerAdapter
-import io.netty.channel.ChannelOutboundHandler
-import io.netty.channel.ChannelPromise
-import net.woggioni.rbcs.server.event.RequestCompletedEvent
-import java.net.SocketAddress
-
-class ResponseCapHandler : ChannelInboundHandlerAdapter(), ChannelOutboundHandler {
-    val bufferedMessages = mutableListOf<Any>()
-
-    override fun bind(ctx: ChannelHandlerContext, localAddress: SocketAddress, promise: ChannelPromise) {
-        ctx.bind(localAddress, promise)
-    }
-
-    override fun connect(
-        ctx: ChannelHandlerContext,
-        remoteAddress: SocketAddress,
-        localAddress: SocketAddress,
-        promise: ChannelPromise
-    ) {
-        ctx.connect(remoteAddress, localAddress, promise)
-    }
-
-    override fun disconnect(ctx: ChannelHandlerContext, promise: ChannelPromise) {
-        ctx.disconnect(promise)
-    }
-
-    override fun close(ctx: ChannelHandlerContext, promise: ChannelPromise) {
-        ctx.close(promise)
-    }
-
-    override fun deregister(ctx: ChannelHandlerContext, promise: ChannelPromise) {
-        ctx.deregister(promise)
-    }
-
-    override fun read(ctx: ChannelHandlerContext) {
-        ctx.read()
-    }
-
-    override fun write(ctx: ChannelHandlerContext, msg: Any, promise: ChannelPromise) {
-        bufferedMessages.add(msg)
-    }
-
-    override fun flush(ctx: ChannelHandlerContext) {
-    }
-
-    override fun userEventTriggered(ctx: ChannelHandlerContext, evt: Any) {
-        if(evt is RequestCompletedEvent) {
-            for(msg in bufferedMessages) ctx.write(msg)
-            ctx.flush()
-            ctx.pipeline().remove(this)
-        }
-    }
-}

rbcs-server/src/main/kotlin/net/woggioni/rbcs/server/handler/ServerHandler.kt

@@ -8,6 +8,7 @@ import io.netty.handler.codec.http.DefaultFullHttpResponse
 import io.netty.handler.codec.http.DefaultHttpContent
 import io.netty.handler.codec.http.DefaultHttpResponse
 import io.netty.handler.codec.http.DefaultLastHttpContent
+import io.netty.handler.codec.http.HttpContent
 import io.netty.handler.codec.http.HttpHeaderNames
 import io.netty.handler.codec.http.HttpHeaderValues
 import io.netty.handler.codec.http.HttpHeaders
@@ -17,7 +18,6 @@ import io.netty.handler.codec.http.HttpResponseStatus
 import io.netty.handler.codec.http.HttpUtil
 import io.netty.handler.codec.http.HttpVersion
 import io.netty.handler.codec.http.LastHttpContent
-import net.woggioni.rbcs.api.CacheHandlerFactory
 import net.woggioni.rbcs.api.CacheValueMetadata
 import net.woggioni.rbcs.api.message.CacheMessage
 import net.woggioni.rbcs.api.message.CacheMessage.CacheContent
@@ -30,10 +30,8 @@ import net.woggioni.rbcs.api.message.CacheMessage.LastCacheContent
 import net.woggioni.rbcs.common.createLogger
 import net.woggioni.rbcs.common.debug
 import net.woggioni.rbcs.common.warn
-import net.woggioni.rbcs.server.event.RequestCompletedEvent
 import net.woggioni.rbcs.server.exception.ExceptionHandler
 import java.nio.file.Path
-import java.util.Locale
 
 class ServerHandler(private val serverPrefix: Path, private val cacheHandlerSupplier : () -> ChannelHandler) :
     ChannelDuplexHandler() {
@@ -47,6 +45,15 @@ class ServerHandler(private val serverPrefix: Path, private val cacheHandlerSupp
     private var keepAlive = true
     private var pipelinedRequests = 0
 
+    private fun newRequest() {
+        pipelinedRequests += 1
+    }
+
+    private fun requestCompleted(ctx : ChannelHandlerContext) {
+        pipelinedRequests -= 1
+        if(pipelinedRequests == 0) ctx.read()
+    }
+
     private fun resetRequestMetadata() {
         httpVersion = HttpVersion.HTTP_1_1
         keepAlive = true
@@ -65,22 +72,44 @@ class ServerHandler(private val serverPrefix: Path, private val cacheHandlerSupp
         }
     }
 
+    private var cacheRequestInProgress : Boolean = false
+
+    override fun handlerAdded(ctx: ChannelHandlerContext) {
+        ctx.read()
+    }
 
     override fun channelRead(ctx: ChannelHandlerContext, msg: Any) {
         when (msg) {
             is HttpRequest -> handleRequest(ctx, msg)
+            is HttpContent -> {
+                if(cacheRequestInProgress) {
+                    if(msg is LastHttpContent) {
+                        super.channelRead(ctx, LastCacheContent(msg.content().retain()))
+                        cacheRequestInProgress = false
+                    } else {
+                        super.channelRead(ctx, CacheContent(msg.content().retain()))
+                    }
+                    msg.release()
+                } else {
+                    super.channelRead(ctx, msg)
+                }
+            }
             else -> super.channelRead(ctx, msg)
         }
     }
 
+    override fun channelReadComplete(ctx: ChannelHandlerContext) {
+        super.channelReadComplete(ctx)
+        if(cacheRequestInProgress) {
+            ctx.read()
+        }
+    }
 
     override fun write(ctx: ChannelHandlerContext, msg: Any, promise: ChannelPromise?) {
         if (msg is CacheMessage) {
             try {
                 when (msg) {
                     is CachePutResponse -> {
-                        pipelinedRequests -= 1
-                        ctx.fireUserEventTriggered(RequestCompletedEvent())
                         val response = DefaultFullHttpResponse(httpVersion, HttpResponseStatus.CREATED)
                         val keyBytes = msg.key.toByteArray(Charsets.UTF_8)
                         response.headers().apply {
@@ -92,16 +121,18 @@ class ServerHandler(private val serverPrefix: Path, private val cacheHandlerSupp
                         val buf = ctx.alloc().buffer(keyBytes.size).apply {
                             writeBytes(keyBytes)
                         }
-                        ctx.writeAndFlush(DefaultLastHttpContent(buf))
+                        ctx.writeAndFlush(DefaultLastHttpContent(buf)).also {
+                            requestCompleted(ctx)
+                        }
                     }
 
                     is CacheValueNotFoundResponse -> {
-                        pipelinedRequests -= 1
-                        ctx.fireUserEventTriggered(RequestCompletedEvent())
                         val response = DefaultFullHttpResponse(httpVersion, HttpResponseStatus.NOT_FOUND)
                         response.headers()[HttpHeaderNames.CONTENT_LENGTH] = 0
                         setKeepAliveHeader(response.headers())
-                        ctx.writeAndFlush(response)
+                        ctx.writeAndFlush(response).also {
+                            requestCompleted(ctx)
+                        }
                     }
 
                     is CacheValueFoundResponse -> {
@@ -118,9 +149,9 @@ class ServerHandler(private val serverPrefix: Path, private val cacheHandlerSupp
                     }
 
                     is LastCacheContent -> {
-                        pipelinedRequests -= 1
+                        ctx.writeAndFlush(DefaultLastHttpContent(msg.content())).also {
-                        ctx.fireUserEventTriggered(RequestCompletedEvent())
+                            requestCompleted(ctx)
-                        ctx.writeAndFlush(DefaultLastHttpContent(msg.content()))
+                        }
                     }
 
                     is CacheContent -> {
@@ -140,9 +171,8 @@ class ServerHandler(private val serverPrefix: Path, private val cacheHandlerSupp
                 resetRequestMetadata()
             }
         } else if(msg is LastHttpContent) {
-            pipelinedRequests -= 1
-            ctx.fireUserEventTriggered(RequestCompletedEvent())
             ctx.write(msg, promise)
+            requestCompleted(ctx)
         } else super.write(ctx, msg, promise)
     }
 
@@ -153,15 +183,12 @@ class ServerHandler(private val serverPrefix: Path, private val cacheHandlerSupp
         if (method === HttpMethod.GET) {
             val path = Path.of(msg.uri()).normalize()
             if (path.startsWith(serverPrefix)) {
+                cacheRequestInProgress = true
                 val relativePath = serverPrefix.relativize(path)
-                val key = relativePath.toString()
+                val key : String = relativePath.toString()
-                if(pipelinedRequests > 0) {
+                newRequest()
-                    ctx.pipeline().addBefore(ExceptionHandler.NAME, null, ResponseCapHandler())
-                }
                 val cacheHandler = cacheHandlerSupplier()
-                ctx.pipeline().addBefore(ExceptionHandler.NAME, null, CacheContentHandler(cacheHandler))
                 ctx.pipeline().addBefore(ExceptionHandler.NAME, null, cacheHandler)
-                pipelinedRequests += 1
                 key.let(::CacheGetRequest)
                     .let(ctx::fireChannelRead)
                     ?: ctx.channel().write(CacheValueNotFoundResponse())
@@ -176,18 +203,15 @@ class ServerHandler(private val serverPrefix: Path, private val cacheHandlerSupp
         } else if (method === HttpMethod.PUT) {
             val path = Path.of(msg.uri()).normalize()
             if (path.startsWith(serverPrefix)) {
+                cacheRequestInProgress = true
                 val relativePath = serverPrefix.relativize(path)
                 val key = relativePath.toString()
                 log.debug(ctx) {
                     "Added value for key '$key' to build cache"
                 }
-                if(pipelinedRequests > 0) {
+                newRequest()
-                    ctx.pipeline().addBefore(ExceptionHandler.NAME, null, ResponseCapHandler())
-                }
                 val cacheHandler = cacheHandlerSupplier()
-                ctx.pipeline().addBefore(ExceptionHandler.NAME, null, CacheContentHandler(cacheHandler))
                 ctx.pipeline().addBefore(ExceptionHandler.NAME, null, cacheHandler)
-                pipelinedRequests += 1
 
                 path.fileName?.toString()
                     ?.let {
@@ -205,11 +229,8 @@ class ServerHandler(private val serverPrefix: Path, private val cacheHandlerSupp
                 ctx.writeAndFlush(response)
             }
         } else if (method == HttpMethod.TRACE) {
-            if(pipelinedRequests > 0) {
+            newRequest()
-                ctx.pipeline().addBefore(ExceptionHandler.NAME, null, ResponseCapHandler())
-            }
             ctx.pipeline().addBefore(ExceptionHandler.NAME, null, TraceHandler)
-            pipelinedRequests += 1
             super.channelRead(ctx, msg)
         } else {
             log.warn(ctx) {