Adding more instrumentation for thread counts and fixing byte count that was ignoring the preamble. Load testing to ensure the server can handle when tons of clients are junk and leave connections open.

Author: voidmain

Diff for: README.md

@@ -2,7 +2,9 @@
 
 **NOTE:** This project is in progress.
 
-The goal of this project is to build a full-featured HTTP server and client in plain Java without the use of any libraries. The client and server will use non-blocking NIO in order to provide the highest performance possible.
+The goal of this project is to build a full-featured HTTP server and client in plain Java without the use of any libraries. The client and server will use Project Loom virtual threads and blocking I/O so that the Java VM will handle all the context switching between virtual threads as they block on I/O.
+
+For more information about Project Loom and virtual threads, here is a good article to read: https://blogs.oracle.com/javamagazine/post/java-virtual-threads
 
 ## Installation
 
@@ -12,20 +14,20 @@ To add this library to your project, you can include this dependency in your Mav
 <dependency>
   <groupId>io.fusionauth</groupId>
   <artifactId>java-http</artifactId>
-  <version>0.3.4</version>
+  <version>0.4.0-RC.2</version>
 </dependency>
 ```
 
 If you are using Gradle, you can add this to your build file:
 
 ```groovy
-implementation 'io.fusionauth:java-http:0.3.4'
+implementation 'io.fusionauth:java-http:0.4.0-RC.2'
 ```
 
 If you are using Savant, you can add this to your build file:
 
 ```groovy
-dependency(id: "io.fusionauth:java-http:0.3.4")
+dependency(id: "io.fusionauth:java-http:0.4.0-RC.2")
 ```
 
 ## Examples Usages:
@@ -43,7 +45,8 @@ public class Example {
       // Handler code goes here
     };
 
-    HTTPServer server = new HTTPServer().withHandler(handler).withListener(new HTTPListenerConfiguration(4242));
+    HTTPServer server = new HTTPServer().withHandler(handler)
+                                        .withListener(new HTTPListenerConfiguration(4242));
     server.start();
     // Use server
     server.close();
@@ -64,7 +67,8 @@ public class Example {
       // Handler code goes here
     };
 
-    try (HTTPServer server = new HTTPServer().withHandler(handler).withListener(new HTTPListenerConfiguration(4242))) {
+    try (HTTPServer server = new HTTPServer().withHandler(handler)
+                                             .withListener(new HTTPListenerConfiguration(4242))) {
       server.start();
       // When this block exits, the server will be shutdown
     }
@@ -88,7 +92,6 @@ public class Example {
     };
 
     HTTPServer server = new HTTPServer().withHandler(handler)
-                                        .withNumberOfWorkerThreads(42)
                                         .withShutdownDuration(Duration.ofSeconds(10L))
                                         .withListener(new HTTPListenerConfiguration(4242));
     server.start();
@@ -204,15 +207,9 @@ The general requirements and roadmap are as follows:
 
 ## FAQ
 
-### Why no Loom?
-
-Project Loom is an exciting development which brings a lot of great new features to Java, such as fibers, continuations and more.
-
-Loom is currently available in Java 19 as a preview feature. Therefore, you can't use it without compiled code that is difficult to use in future Java releases.
-
-This project is anchored to the Java LTS releases to ensure compatibility. Loom will be evaluated once it is out of preview, and available in an LTS version of Java.  
+### Why virtual threads and not NIO?
 
-The next scheduled LTS release will be Java 21 set to release in September 2023. We are looking forward to that release and to see if we can leverage the Loom features in this project. 
+Let's face it, NIO is insanely complex to write and maintain. The first 3 versions of `java-http` used NIO with non-blocking selectors, and we encountered numerous bugs, performance issues, etc. If you compare the `0.3-maintenance` branch with `main` of this project, you'll quickly see that switching to virtual threads and standard blocking I/O made our code **MUCH** simpler.
 
 ## Helping out
 
@@ -225,8 +222,8 @@ We are looking for Java developers that are interested in helping us build the c
 ```bash
 $ mkdir ~/savant
 $ cd ~/savant
-$ wget http://savant.inversoft.org/org/savantbuild/savant-core/2.0.0-RC.6/savant-2.0.0-RC.6.tar.gz
-$ tar xvfz savant-2.0.0-RC.6.tar.gz
-$ ln -s ./savant-2.0.0-RC.6 current
+$ wget http://savant.inversoft.org/org/savantbuild/savant-core/2.0.0-RC.6/savant-2.0.0-RC.7.tar.gz
+$ tar xvfz savant-2.0.0-RC.7.tar.gz
+$ ln -s ./savant-2.0.0-RC.7 current
 $ export PATH=$PATH:~/savant/current/bin/
 ```

Diff for: build.savant

@@ -17,7 +17,7 @@ jackson5Version = "3.0.1"
 restifyVersion = "4.2.1"
 testngVersion = "7.10.2"
 
-project(group: "io.fusionauth", name: "java-http", version: "0.4.0-RC.1", licenses: ["ApacheV2_0"]) {
+project(group: "io.fusionauth", name: "java-http", version: "0.4.0-RC.2", licenses: ["ApacheV2_0"]) {
   workflow {
     fetch {
       // Dependency resolution order:

Diff for: load-tests/self/build.savant

@@ -32,7 +32,7 @@ project(group: "io.fusionauth", name: "self", version: "0.1.0", licenses: ["Apac
 
   dependencies {
     group(name: "compile") {
-      dependency(id: "io.fusionauth:java-http:0.4.0-{integration}")
+      dependency(id: "io.fusionauth:java-http:0.4.0-RC.2.{integration}")
     }
   }
 

Diff for: load-tests/self/self.iml

@@ -10,11 +10,11 @@
     <orderEntry type="module-library">
       <library>
         <CLASSES>
-          <root url="jar://$USER_HOME$/.savant/cache/io/fusionauth/java-http/0.4.0-{integration}/java-http-0.4.0-{integration}.jar!/" />
+          <root url="jar://$USER_HOME$/.savant/cache/io/fusionauth/java-http/0.4.0-RC.2.{integration}/java-http-0.4.0-RC.2.{integration}.jar!/" />
         </CLASSES>
         <JAVADOC />
         <SOURCES>
-          <root url="jar://$USER_HOME$/.savant/cache/io/fusionauth/java-http/0.4.0-{integration}/java-http-0.4.0-{integration}-src.jar!/" />
+          <root url="jar://$USER_HOME$/.savant/cache/io/fusionauth/java-http/0.4.0-RC.2.{integration}/java-http-0.4.0-RC.2.{integration}-src.jar!/" />
         </SOURCES>
       </library>
     </orderEntry>

Diff for: load-tests/self/src/main/java/io/fusionauth/http/load/Main.java

@@ -15,22 +15,19 @@
  */
 package io.fusionauth.http.load;
 
-import java.time.Duration;
-
 import io.fusionauth.http.log.Level;
 import io.fusionauth.http.log.SystemOutLoggerFactory;
-import io.fusionauth.http.server.CountingInstrumenter;
 import io.fusionauth.http.server.HTTPListenerConfiguration;
 import io.fusionauth.http.server.HTTPServer;
+import io.fusionauth.http.server.ThreadSafeCountingInstrumenter;
 
 public class Main {
   public static void main(String[] args) throws Exception {
     SystemOutLoggerFactory.FACTORY.getLogger(Object.class).setLevel(Level.Debug);
 
     System.out.println("Starting java-http server");
-    CountingInstrumenter instrumenter = new CountingInstrumenter();
+    var instrumenter = new ThreadSafeCountingInstrumenter();
     try (HTTPServer ignore = new HTTPServer().withHandler(new LoadHandler())
-                                             .withClientTimeout(Duration.ofSeconds(100L))
                                              .withCompressByDefault(false)
                                              .withInstrumenter(instrumenter)
                                              .withListener(new HTTPListenerConfiguration(8080))
@@ -39,9 +36,10 @@ public static void main(String[] args) throws Exception {
 
       for (int i = 0; i < 1_000; i++) {
         Thread.sleep(10_000);
-        System.out.printf("Current stats. Bad requests [%s]. Bytes read [%s]. Bytes written [%s]. Chunked requests [%s]. Chunked responses [%s]. Closed connections [%s]. Connections [%s]. Started [%s].\n",
+        System.out.printf("Current stats. Bad requests [%s]. Bytes read [%s]. Bytes written [%s]. Chunked requests [%s]. Chunked responses [%s]. Closed connections [%s]. Connections [%s]. Started [%s]. Virtual threads [%s].\n",
             instrumenter.getBadRequests(), instrumenter.getBytesRead(), instrumenter.getBytesWritten(), instrumenter.getChunkedRequests(),
-            instrumenter.getChunkedResponses(), instrumenter.getClosedConnections(), instrumenter.getConnections(), instrumenter.getStartedCount());
+            instrumenter.getChunkedResponses(), instrumenter.getClosedConnections(), instrumenter.getConnections(), instrumenter.getStartedCount(),
+            instrumenter.getThreadCount());
       }
 
       System.out.println("Shutting down java-http server");

Diff for: load-tests/self/src/main/java/io/fusionauth/http/load/SocketHammer.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2024, FusionAuth, All Rights Reserved
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific
+ * language governing permissions and limitations under the License.
+ */
+package io.fusionauth.http.load;
+
+import java.io.OutputStream;
+import java.net.Socket;
+import java.util.ArrayList;
+import java.util.List;
+
+public class SocketHammer {
+  public static void main(String[] args) throws Exception {
+    List<Socket> sockets = new ArrayList<>();
+
+    for (int i = 0; i < 10_000; i++) {
+      try {
+        Socket socket = new Socket("localhost", 8080);
+        sockets.add(socket);
+        System.out.println(i);
+
+        OutputStream outputStream = socket.getOutputStream();
+        outputStream.write("GET".getBytes());
+        outputStream.flush();
+      } catch (Exception e) {
+        //Smother
+//        System.out.println("Failed");
+      }
+    }
+
+    Thread.sleep(10_000);
+    for (Socket socket : sockets) {
+      socket.close();
+    }
+
+    System.out.println("Done");
+  }
+}

Diff for: load-tests/self/src/main/script/hammer.sh

@@ -0,0 +1,39 @@
+#!/usr/bin/env bash
+
+#
+# Copyright (c) 2022, FusionAuth, All Rights Reserved
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+# either express or implied. See the License for the specific
+# language governing permissions and limitations under the License.
+#
+
+# Grab the path
+if [[ ! -d lib ]]; then
+  echo "Unable to locate library files needed to run the load tests. [lib]"
+  exit 1
+fi
+
+CLASSPATH=.
+for f in lib/*.jar; do
+  CLASSPATH=${CLASSPATH}:${f}
+done
+
+suspend=""
+if [[ $# -gt 1 && $1 == "--suspend" ]]; then
+  suspend="-agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=8000"
+  shift
+fi
+
+for i in {1..5} ; do
+  echo "${i}"
+  ~/dev/java/current21/bin/java ${suspend} -cp "${CLASSPATH}" io.fusionauth.http.load.SocketHammer &
+done

Diff for: src/main/java/io/fusionauth/http/server/CountingInstrumenter.java

@@ -16,10 +16,12 @@
 package io.fusionauth.http.server;
 
 /**
- * A simple counting instrumenter for the HTTPServer.
+ * A simple counting instrumenter for the HTTPServer. This is not thread safe, so if you need accurate data, you'll want to use the
+ * {@link ThreadSafeCountingInstrumenter}.
  *
  * @author Brian Pontarelli
  */
+@SuppressWarnings("unused")
 public class CountingInstrumenter implements Instrumenter {
   private long badRequests;
 
@@ -37,6 +39,8 @@ public class CountingInstrumenter implements Instrumenter {
 
   private long startedCount;
 
+  private long threadCount;
+
   @Override
   public void acceptedConnection() {
     connections++;
@@ -94,6 +98,10 @@ public long getStartedCount() {
     return startedCount;
   }
 
+  public long getThreadCount() {
+    return threadCount;
+  }
+
   @Override
   public void readFromClient(long bytes) {
     bytesRead += bytes;
@@ -104,6 +112,16 @@ public void serverStarted() {
     startedCount++;
   }
 
+  @Override
+  public void threadExited() {
+    threadCount--;
+  }
+
+  @Override
+  public void threadStarted() {
+    threadCount++;
+  }
+
   @Override
   public void wroteToClient(long bytes) {
     bytesWritten += bytes;

Diff for: src/main/java/io/fusionauth/http/server/Instrumenter.java

@@ -58,6 +58,16 @@ public interface Instrumenter {
    */
   void serverStarted();
 
+  /**
+   * Signals that a virtual thread has exited.
+   */
+  void threadExited();
+
+  /**
+   * Signals that a virtual thread has started.
+   */
+  void threadStarted();
+
   /**
    * Called when bytes are written to a client.
    *