Create a load testing EPP client (#2415)

* Create a load testing EPP client.

This code is mostly based off of what was used for a past EPP load testing client that can be found in Google3 at https://source.corp.google.com/piper///depot/google3/experimental/users/jianglai/proxy/java/google/registry/proxy/client/

I modified the old client to be open-source friendly and use Gradle.

For now, this only performs a login and logout command, I will further expand on this in later PRs to add other EPP commands so that we can truly load test the system.

* Small changes

* Remove unnecessary build dep

* Add gradle build tasks

* Small fixes

* Add an instances setUp and cleanUp script

* More modifications to instance setup scripts

* change to ubuntu instance

* Add comment to make ssh work

config/presubmits.py

@@ -100,12 +100,12 @@ PRESUBMITS = {
                    {"node_modules/"}, REQUIRED):
         "Source files must end in a newline.",
 
-    # System.(out|err).println should only appear in tools/
+    # System.(out|err).println should only appear in tools/ or load-testing/
     PresubmitCheck(
         r".*\bSystem\.(out|err)\.print", "java", {
             "StackdriverDashboardBuilder.java", "/tools/", "/example/",
-            "RegistryTestServerMain.java", "TestServerExtension.java",
-            "FlowDocumentationTool.java"
+            "/load-testing/", "RegistryTestServerMain.java",
+            "TestServerExtension.java", "FlowDocumentationTool.java"
         }):
         "System.(out|err).println is only allowed in tools/ packages. Please "
         "use a logger instead.",

load-testing/build.gradle

@@ -0,0 +1,54 @@
+// Copyright 2024 The Nomulus Authors. 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.
+
+apply plugin: 'java'
+
+createUberJar('buildLoadTestClient', 'loadTest', 'google.registry.client.EppClient')
+
+dependencies {
+    def deps = rootProject.dependencyMap
+    implementation deps['joda-time:joda-time']
+    implementation deps['io.netty:netty-buffer']
+    implementation deps['io.netty:netty-codec']
+    implementation deps['io.netty:netty-codec-http']
+    implementation deps['io.netty:netty-common']
+    implementation deps['io.netty:netty-handler']
+    implementation deps['io.netty:netty-transport']
+    implementation deps['com.google.guava:guava']
+    implementation deps['org.bouncycastle:bcpg-jdk18on']
+    implementation deps['org.bouncycastle:bcpkix-jdk18on']
+    implementation deps['org.bouncycastle:bcprov-jdk18on']
+    implementation deps['org.jcommander:jcommander']
+    implementation deps['com.google.flogger:flogger']
+    runtimeOnly deps['com.google.flogger:flogger-system-backend']
+}
+
+task makeStagingDirectory {
+    mkdir layout.buildDirectory.dir('stage')
+}
+
+task copyFilesToStaging(dependsOn: makeStagingDirectory, type: Copy) {
+    from layout.buildDirectory.file('libs/loadTest.jar'), "${projectDir}/certificate.pem", "${projectDir}/key.pem"
+    into layout.buildDirectory.dir('stage')
+}
+
+task deployLoadTestsToInstances (dependsOn: copyFilesToStaging, type: Exec) {
+    executable "sh"
+    workingDir "${projectDir}/"
+    args "-c", "./deploy.sh"
+}
+
+test {
+    useJUnitPlatform()
+}

load-testing/deploy.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+# Copyright 2024 The Nomulus Authors. 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.
+
+HOSTS=$(gcloud compute instances list | awk '/^loadtest/ { print $5 }')
+for host in $HOSTS; do rsync -avz ./build/stage/ $host:test-client/; done

load-testing/instanceCleanUp.sh

@@ -0,0 +1,19 @@
+#!/bin/bash
+# Copyright 2024 The Nomulus Authors. 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.
+
+# Find and delete the instances used for load testing
+
+gcloud compute instances list --filter="name ~ loadtest.*" --zones us-east4-a \
+--format="value(name)" | xargs gcloud compute instances delete --zone us-east4-a

load-testing/instanceSetUp.sh

@@ -0,0 +1,39 @@
+#!/bin/bash
+# Copyright 2024 The Nomulus Authors. 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.
+
+# Create the instances - modify this number for the amount of instances you
+# would like to use for your load test
+gcloud compute instances create loadtest-{1..2} --machine-type g1-small \
+--image-family ubuntu-2204-lts --image-project ubuntu-os-cloud --zone us-east4-a
+
+sleep 10
+
+# Get all the created load tests instances
+HOSTS=$(gcloud compute instances list | awk '/^loadtest/ { print $5 }')
+
+#Install rsync and Java - Retry is needed here since ssh connection will fail until instances are fully provisioned
+for host in $HOSTS;
+  do
+    for i in {1..60}; do
+      if ssh $host 'sudo apt-get -y update &&
+                    sudo apt-get -y upgrade &&
+                    sudo apt-get -y install rsync &&
+                    sudo apt-get -y install openjdk-21-jdk'; then
+        break
+      else
+        sleep 5
+      fi
+    done
+  done

load-testing/run.sh

@@ -0,0 +1,21 @@
+#!/bin/bash
+# Copyright 2024 The Nomulus Authors. 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.
+
+HOSTS=$(gcloud compute instances list | awk '/^loadtest/ { print $5 }')
+
+for host in $HOSTS;
+  do ssh $host 'cd test-client/ &&
+    java -jar loadTest.jar --host epp.example --certificate certificate.pem -k key.pem -pw examplePassword -ft';
+  done

load-testing/src/main/java/google/registry/client/EppClient.java

@@ -0,0 +1,353 @@
+// Copyright 2024 The Nomulus Authors. 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 google.registry.client;
+
+import static com.google.common.io.Resources.getResource;
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static org.joda.time.DateTimeZone.UTC;
+
+import com.beust.jcommander.IStringConverter;
+import com.beust.jcommander.JCommander;
+import com.beust.jcommander.Parameter;
+import com.beust.jcommander.Parameters;
+import com.google.common.collect.ImmutableList;
+import com.google.common.io.Files;
+import com.google.common.io.Resources;
+import io.netty.bootstrap.Bootstrap;
+import io.netty.channel.Channel;
+import io.netty.channel.ChannelFuture;
+import io.netty.channel.ChannelInitializer;
+import io.netty.channel.EventLoopGroup;
+import io.netty.channel.nio.NioEventLoopGroup;
+import io.netty.channel.socket.SocketChannel;
+import io.netty.channel.socket.nio.NioSocketChannel;
+import io.netty.handler.codec.LengthFieldBasedFrameDecoder;
+import io.netty.handler.codec.LengthFieldPrepender;
+import io.netty.handler.logging.LogLevel;
+import io.netty.handler.logging.LoggingHandler;
+import io.netty.handler.ssl.SslContextBuilder;
+import io.netty.handler.ssl.util.InsecureTrustManagerFactory;
+import io.netty.util.AttributeKey;
+import io.netty.util.concurrent.Promise;
+import java.io.ByteArrayInputStream;
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.security.KeyPair;
+import java.security.Security;
+import java.security.cert.CertificateException;
+import java.security.cert.X509Certificate;
+import java.time.Duration;
+import java.time.ZoneOffset;
+import java.time.ZonedDateTime;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+import org.bouncycastle.cert.X509CertificateHolder;
+import org.bouncycastle.cert.jcajce.JcaX509CertificateConverter;
+import org.bouncycastle.jce.provider.BouncyCastleProvider;
+import org.bouncycastle.openssl.PEMKeyPair;
+import org.bouncycastle.openssl.PEMParser;
+import org.bouncycastle.openssl.jcajce.JcaPEMKeyConverter;
+import org.joda.time.DateTime;
+
+/** A simple EPP client that can be used for load testing. */
+@Parameters(separators = " =")
+@SuppressWarnings("FutureReturnValueIgnored")
+public class EppClient implements Runnable {
+
+  static {
+    Security.addProvider(new BouncyCastleProvider());
+  }
+
+  private static final String LOGIN_FILE = "login.xml";
+  private static final String LOGOUT_FILE = "logout.xml";
+  static final AttributeKey<ArrayList<ZonedDateTime>> REQUEST_SENT =
+      AttributeKey.valueOf("REQUEST_SENT");
+  static final AttributeKey<ArrayList<ZonedDateTime>> RESPONSE_RECEIVED =
+      AttributeKey.valueOf("RESPONSE_RECEIVED");
+  static final AttributeKey<Integer> CHANNEL_NUMBER = AttributeKey.valueOf("CHANNEL_NUMBER");
+  static final AttributeKey<Path> LOGGING_LOCATION = AttributeKey.valueOf("LOGGING_LOCATION");
+  static final AttributeKey<Boolean> FORCE_TERMINATE = AttributeKey.valueOf("FORCE_TERMINATE");
+  static final AttributeKey<ExecutorService> LOGGING_EXECUTOR =
+      AttributeKey.valueOf("LOGGING_EXECUTOR");
+  static final AttributeKey<Iterator<byte[]>> INPUT_ITERATOR =
+      AttributeKey.valueOf("INPUT_ITERATOR");
+  static final AttributeKey<Promise<Void>> LOGGING_REQUEST_COMPLETE =
+      AttributeKey.valueOf("LOGGING_REQUEST_COMPLETE");
+  private static final int PORT = 700;
+  private static final int TIMEOUT_SECONDS = 600;
+
+  public static class InetAddressConverter implements IStringConverter<InetAddress> {
+
+    @Override
+    public InetAddress convert(String host) {
+      try {
+        return InetAddress.getByName(host);
+      } catch (UnknownHostException e) {
+        throw new IllegalArgumentException(host, e);
+      }
+    }
+  }
+
+  @Parameter(
+      names = {"--help"},
+      description = "Print this help message.",
+      help = true)
+  private boolean help = false;
+
+  @Parameter(
+      names = {"--host", "-h"},
+      description = "Epp server hostname/IP to connect to.",
+      converter = InetAddressConverter.class,
+      required = true)
+  private InetAddress host = null;
+
+  @Parameter(
+      names = {"--certificate"},
+      description = "Certificate pem file.",
+      required = true)
+  private String certFileName = null;
+
+  @Parameter(
+      names = {"--key", "-k"},
+      description = "Private key pem file.",
+      required = true)
+  private String keyFileName = null;
+
+  @Parameter(
+      names = {"--connections", "-cn"},
+      description = "Number of connections that are made to the EPP server.")
+  private int connections = 1;
+
+  @Parameter(
+      names = {"--client", "-c"},
+      description = "Registrar client id.")
+  private String client = "proxy";
+
+  @Parameter(
+      names = {"--password", "-pw"},
+      description = "Registrar password.")
+  private String password = "abcde12345";
+
+  @Parameter(
+      names = {"--force_terminate", "-ft"},
+      description = "Whether to explicitly close the connection after receiving a logout response.")
+  private boolean forceTerminate = false;
+
+  public static void main(String[] args) {
+    EppClient eppClient = new EppClient();
+    JCommander jCommander = new JCommander(eppClient);
+    jCommander.parse(args);
+    if (eppClient.help) {
+      jCommander.usage();
+      return;
+    }
+    eppClient.run();
+  }
+
+  private ImmutableList<String> makeInputList(ZonedDateTime now) {
+    ImmutableList.Builder<String> templatesList = ImmutableList.builder();
+    ImmutableList.Builder<String> inputList = ImmutableList.builder();
+    templatesList.add(readStringFromFile(LOGIN_FILE));
+    templatesList.add(readStringFromFile(LOGOUT_FILE));
+    for (String template : templatesList.build()) {
+      inputList.add(
+          template
+              .replace("@@CLIENT@@", client)
+              .replace("@@PASSWORD@@", password)
+              .replace("@@NOW@@", now.toString()));
+    }
+    return inputList.build();
+  }
+
+  private static String readStringFromFile(String filename) {
+    try {
+      return Resources.toString(getResource(EppClient.class, "resources/" + filename), UTF_8);
+    } catch (IOException e) {
+      throw new IllegalArgumentException("Cannot read from file: resources/" + filename);
+    }
+  }
+
+  private static KeyPair getKeyPair(String filename) throws IOException {
+    byte[] keyBytes = Files.asCharSource(new File(filename), UTF_8).read().getBytes(UTF_8);
+    try {
+      PEMKeyPair pemPair =
+          (PEMKeyPair)
+              new PEMParser(new InputStreamReader(new ByteArrayInputStream(keyBytes), UTF_8))
+                  .readObject();
+      return new JcaPEMKeyConverter().setProvider("BC").getKeyPair(pemPair);
+    } catch (IOException e) {
+      throw new RuntimeException(e);
+    }
+  }
+
+  private static X509Certificate getCertificate(String filename) throws IOException {
+    byte[] certificateBytes = Files.asCharSource(new File(filename), UTF_8).read().getBytes(UTF_8);
+    try {
+      X509CertificateHolder certificateHolder =
+          (X509CertificateHolder)
+              new PEMParser(
+                      new InputStreamReader(new ByteArrayInputStream(certificateBytes), UTF_8))
+                  .readObject();
+      return new JcaX509CertificateConverter().setProvider("BC").getCertificate(certificateHolder);
+    } catch (IOException | CertificateException e) {
+      throw new RuntimeException(e);
+    }
+  }
+
+  private ChannelInitializer<SocketChannel> makeChannelInitializer(
+      String outputFolder, ImmutableList<ExecutorService> loggingExecutors) throws IOException {
+    return new ChannelInitializer<>() {
+
+      private final ImmutableList<String> inputList =
+          makeInputList(ZonedDateTime.now(ZoneOffset.UTC));
+      private final KeyPair key = getKeyPair(keyFileName);
+      private final X509Certificate cert = getCertificate(certFileName);
+      private final LoggingHandler loggingHandler = new LoggingHandler(LogLevel.INFO);
+      private final EppClientHandler eppClientHandler = new EppClientHandler();
+
+      @Override
+      protected void initChannel(SocketChannel ch) throws Exception {
+        ch.attr(REQUEST_SENT).set(new ArrayList<>());
+        ch.attr(RESPONSE_RECEIVED).set(new ArrayList<>());
+        Path loggingLocation =
+            Paths.get(String.format("%s/%d.log", outputFolder, ch.attr(CHANNEL_NUMBER).get()));
+        ch.attr(LOGGING_LOCATION).set(loggingLocation);
+        ch.attr(FORCE_TERMINATE).set(forceTerminate);
+        ch.attr(LOGGING_EXECUTOR)
+            .set(loggingExecutors.get(ch.attr(CHANNEL_NUMBER).get() % loggingExecutors.size()));
+
+        ch.attr(INPUT_ITERATOR)
+            .set(
+                inputList.stream()
+                    .map(
+                        (String str) ->
+                            str.replace(
+                                    "@@CHANNEL_NUMBER@@",
+                                    String.valueOf(ch.attr(CHANNEL_NUMBER).get()))
+                                .replace("@@CHANNEL_NUMBER_MODULO@@", String.valueOf(0))
+                                .getBytes(UTF_8))
+                    .iterator());
+
+        ch.pipeline()
+            .addLast(
+                SslContextBuilder.forClient()
+                    .keyManager(key.getPrivate(), cert)
+                    .trustManager(InsecureTrustManagerFactory.INSTANCE)
+                    .build()
+                    .newHandler(ch.alloc(), host.getHostName(), PORT));
+        ch.pipeline().addLast(new LengthFieldBasedFrameDecoder(512 * 1024, 0, 4, -4, 4));
+        ch.pipeline().addLast(new LengthFieldPrepender(4, true));
+        ch.pipeline().addLast(loggingHandler);
+        ch.pipeline().addLast(eppClientHandler);
+      }
+    };
+  }
+
+  private static String createOutputFolder(String folderName) {
+    Path folder = Paths.get(folderName);
+    if (!folder.toFile().exists()) {
+      folder.toFile().mkdirs();
+    }
+    System.out.printf("\nOutputs saved at %s\n", folder);
+    return folderName;
+  }
+
+  @Override
+  public void run() {
+    String outputFolder = createOutputFolder(String.format("load-tests/%s", DateTime.now(UTC)));
+    ImmutableList.Builder<ExecutorService> builder = ImmutableList.builderWithExpectedSize(5);
+    for (int i = 0; i < 5; ++i) {
+      builder.add(Executors.newSingleThreadExecutor());
+    }
+    final ImmutableList<ExecutorService> loggingExecutors = builder.build();
+
+    EventLoopGroup eventLoopGroup = new NioEventLoopGroup();
+
+    try {
+      Bootstrap bootstrap =
+          new Bootstrap()
+              .group(eventLoopGroup)
+              .channel(NioSocketChannel.class)
+              .handler(makeChannelInitializer(outputFolder, loggingExecutors));
+
+      List<ChannelFuture> channelFutures = new ArrayList<>();
+
+      // Three requests: hello (from the proxy), login and logout.
+      int requestPerConnection = 3;
+
+      for (int i = 0; i < connections; i++) {
+        bootstrap.attr(CHANNEL_NUMBER, i);
+        channelFutures.add(
+            bootstrap
+                .connect(host, PORT)
+                .addListener(
+                    (ChannelFuture cf) -> {
+                      if (!cf.isSuccess()) {
+                        System.out.printf("Cannot connect to %s:%s\n", host, PORT);
+                      }
+                    }));
+      }
+
+      LinkedHashSet<Integer> killedConnections = new LinkedHashSet<>();
+
+      // Wait for all channels to close.
+      for (ChannelFuture channelFuture : channelFutures) {
+        Channel channel = channelFuture.syncUninterruptibly().channel();
+        int channelNumber = channel.attr(CHANNEL_NUMBER).get();
+        if (!channel
+            .closeFuture()
+            .awaitUninterruptibly(
+                TIMEOUT_SECONDS * 1000
+                    - Duration.between(
+                            channel.attr(REQUEST_SENT).get().getFirst(),
+                            ZonedDateTime.now(ZoneOffset.UTC))
+                        .toMillis())) {
+          channel.close().syncUninterruptibly();
+          killedConnections.add(channelNumber);
+        }
+      }
+
+      System.out.println();
+      System.out.println("====== SUMMARY ======");
+      System.out.printf("Number of connections: %d\n", connections);
+      System.out.printf("Number of requests per connection: %d\n", requestPerConnection);
+      if (!killedConnections.isEmpty()) {
+        System.out.printf("Force killed connections (%d): ", killedConnections.size());
+        for (int channelNumber : killedConnections) {
+          System.out.printf("%d ", channelNumber);
+        }
+        System.out.print("\n");
+      }
+
+      eventLoopGroup.shutdownGracefully();
+
+      channelFutures.forEach(
+          channelFuture -> {
+            channelFuture.channel().attr(LOGGING_REQUEST_COMPLETE).get().syncUninterruptibly();
+          });
+      loggingExecutors.forEach(ExecutorService::shutdown);
+    } catch (IOException e) {
+      throw new RuntimeException(e);
+    }
+  }
+}

load-testing/src/main/java/google/registry/client/EppClientHandler.java

@@ -0,0 +1,153 @@
+// Copyright 2024 The Nomulus Authors. 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 google.registry.client;
+
+import static google.registry.client.EppClient.CHANNEL_NUMBER;
+import static google.registry.client.EppClient.FORCE_TERMINATE;
+import static google.registry.client.EppClient.INPUT_ITERATOR;
+import static google.registry.client.EppClient.LOGGING_EXECUTOR;
+import static google.registry.client.EppClient.LOGGING_LOCATION;
+import static google.registry.client.EppClient.LOGGING_REQUEST_COMPLETE;
+import static google.registry.client.EppClient.REQUEST_SENT;
+import static google.registry.client.EppClient.RESPONSE_RECEIVED;
+import static java.nio.file.StandardOpenOption.APPEND;
+
+import com.google.common.flogger.FluentLogger;
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.Unpooled;
+import io.netty.channel.Channel;
+import io.netty.channel.ChannelDuplexHandler;
+import io.netty.channel.ChannelHandler.Sharable;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.channel.ChannelPromise;
+import io.netty.util.ReferenceCountUtil;
+import io.netty.util.concurrent.Promise;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.time.ZoneOffset;
+import java.time.ZonedDateTime;
+
+/** Handler that sends EPP requests and receives EPP responses. */
+@SuppressWarnings("FutureReturnValueIgnored")
+@Sharable
+public class EppClientHandler extends ChannelDuplexHandler {
+
+  private static final FluentLogger logger = FluentLogger.forEnclosingClass();
+
+  static class FileWriter implements Runnable {
+
+    private final Path loggingLocation;
+    private final byte[] contents;
+    private final ZonedDateTime time;
+
+    FileWriter(Path loggingLocation, byte[] contents, ZonedDateTime time) {
+      this.loggingLocation = loggingLocation;
+      this.contents = contents;
+      this.time = time;
+    }
+
+    @Override
+    public void run() {
+      try {
+        if (!Files.exists(loggingLocation)) {
+          Files.createFile(loggingLocation);
+        }
+        Files.writeString(loggingLocation, time.toString() + "\n", APPEND);
+        Files.write(loggingLocation, contents, APPEND);
+      } catch (IOException e) {
+        throw new RuntimeException(e);
+      }
+    }
+  }
+
+  @Override
+  public void channelRegistered(ChannelHandlerContext ctx) throws Exception {
+    ZonedDateTime now = ZonedDateTime.now(ZoneOffset.UTC);
+    ctx.channel().attr(REQUEST_SENT).get().add(now);
+    ctx.channel().attr(LOGGING_REQUEST_COMPLETE).set(ctx.executor().newPromise());
+    super.channelRegistered(ctx);
+  }
+
+  @Override
+  public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
+    Promise<Void> loggingCompletePromise = ctx.channel().attr(LOGGING_REQUEST_COMPLETE).get();
+    if (!loggingCompletePromise.isDone()) {
+      loggingCompletePromise.setSuccess(null);
+    }
+    logger.atWarning().withCause(cause).log(
+        "Connection %d closed.", ctx.channel().attr(CHANNEL_NUMBER).get());
+  }
+
+  @Override
+  public void channelRead(ChannelHandlerContext ctx, Object msg) {
+    ZonedDateTime now = ZonedDateTime.now(ZoneOffset.UTC);
+    Channel ch = ctx.channel();
+    ctx.channel().attr(RESPONSE_RECEIVED).get().add(now);
+    if (msg instanceof ByteBuf buffer) {
+      byte[] contents = new byte[buffer.readableBytes()];
+      buffer.readBytes(contents);
+      ReferenceCountUtil.release(buffer);
+      if (ch.attr(LOGGING_LOCATION).get() != null) {
+        ch.attr(LOGGING_EXECUTOR)
+            .get()
+            .submit(new FileWriter(ch.attr(LOGGING_LOCATION).get(), contents, now));
+      }
+      if (ch.attr(INPUT_ITERATOR).get().hasNext()) {
+        ch.writeAndFlush(ch.attr(INPUT_ITERATOR).get().next());
+      } else {
+        ch.attr(LOGGING_REQUEST_COMPLETE).get().setSuccess(null);
+        if (ch.attr(FORCE_TERMINATE).get()) {
+          ch.close();
+        }
+      }
+    }
+  }
+
+  @Override
+  public void write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise) {
+    ZonedDateTime now = ZonedDateTime.now(ZoneOffset.UTC);
+    Channel ch = ctx.channel();
+    ctx.channel().attr(REQUEST_SENT).get().add(now);
+    if (msg instanceof byte[] outputBytes) {
+      ByteBuf buffer = Unpooled.buffer();
+      buffer.writeBytes(outputBytes);
+      ctx.write(buffer, promise);
+      if (ch.attr(LOGGING_LOCATION).get() != null) {
+        ch.attr(LOGGING_EXECUTOR)
+            .get()
+            .submit(new FileWriter(ch.attr(LOGGING_LOCATION).get(), outputBytes, now));
+      }
+    }
+  }
+
+  @Override
+  public void close(ChannelHandlerContext ctx, ChannelPromise promise) throws Exception {
+    Promise<Void> loggingCompletePromise = ctx.channel().attr(LOGGING_REQUEST_COMPLETE).get();
+    if (!loggingCompletePromise.isDone()) {
+      loggingCompletePromise.setSuccess(null);
+    }
+    super.close(ctx, promise);
+  }
+
+  @Override
+  public void channelInactive(ChannelHandlerContext ctx) throws Exception {
+    Promise<Void> loggingCompletePromise = ctx.channel().attr(LOGGING_REQUEST_COMPLETE).get();
+    if (!loggingCompletePromise.isDone()) {
+      loggingCompletePromise.setSuccess(null);
+    }
+    super.channelInactive(ctx);
+  }
+}

load-testing/src/main/java/google/registry/client/README.md

@@ -0,0 +1,73 @@
+## EPP Load Testing Client
+
+This project contains an EPP client that can be use for load testing the full 
+registry platform. All the below commands should be run from the merged root.
+
+### Setting up the test instances
+
+* If you have not done s yet, you will need to set up ssh keys in your 
+[GCE metadata](https://pantheon.corp.google.com/compute/metadata?resourceTab=sshkeys):
+
+* To create however many GCE instances you want to run on, modify the 
+`instanceSetUp.sh` file to include the correct number of instances. 
+
+* Run the instance set up script to create and configure each of the GCE 
+instances to be used for load testing:
+
+  ```shell
+  $ load-testing/instanceSetUp.sh
+  ```
+
+* Verify that the IP address of any created instances is in the allowlist of the
+  proxy registrar user.
+    * Use the below command to get the IP addresses of the created instances.
+
+        ```shell
+        $ (gcloud compute instances list | awk '/^loadtest/ { print $5 }')
+        ```
+
+    * Check the proxy registrar's current allow list
+
+      ```shell
+      $ nomulus -e sandbox get_registrar proxy | grep ipAddressAllowList
+      ```
+
+    * All of your host ip addresses should match a netmask specified in the proxy
+      allow list. If not, you'll need to redefine the list:
+
+      ```shell
+      $ nomulus -e sandbox update_registrar proxy --ip_allow_list=<new-comma-separated-allowlist>
+      ```
+
+
+### Running the client
+
+* From the merged root build the load testing client:
+  ```shell
+  $ ./nom_build :load-testing:buildLoadTestClient
+    ```
+
+* Deploy the client to the GCE instances (this will create a local staging 
+directory and deploy it to each of your previously created loadtest GCE instances): 
+  ```shell
+  $ ./nom_build :load-testing:deployLoadTestsToInstances
+    ```
+
+* Run the load test. Configurations of the load test can be made by configuring 
+this `run.sh` file locally.
+
+    ```shell
+    $ load-testing/run.sh
+    ```
+
+### Cleanup
+
+* Run the instance clean up script to delete the created instances
+
+    ```shell
+    $ load-testing/instanceCleanUp.sh
+    ```
+  
+* You may want to remove any host key fingerprints for those hosts from your ~/.ssh/known_hosts file (these IPs tend to get reused with new host keys)
+
+

load-testing/src/main/java/google/registry/client/resources/login.xml

@@ -0,0 +1,19 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
+<command>
+  <login>
+    <clID>@@CLIENT@@</clID>
+    <pw>@@PASSWORD@@</pw>
+    <options>
+      <version>1.0</version>
+      <lang>en</lang>
+    </options>
+    <svcs>
+      <objURI>urn:ietf:params:xml:ns:host-1.0</objURI>
+      <objURI>urn:ietf:params:xml:ns:domain-1.0</objURI>
+      <objURI>urn:ietf:params:xml:ns:contact-1.0</objURI>
+    </svcs>
+  </login>
+  <clTRID>epp-client-login-@@NOW@@-@@CHANNEL_NUMBER@@</clTRID>
+</command>
+</epp>

load-testing/src/main/java/google/registry/client/resources/logout.xml

@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<epp xmlns="urn:ietf:params:xml:ns:epp-1.0">
+  <command>
+    <logout/>
+    <clTRID>epp-client-logout-@@NOW@@-@@CHANNEL_NUMBER@@</clTRID>
+  </command>
+</epp>

settings.gradle

@@ -47,3 +47,4 @@ include 'services:tools'
 include 'services:pubapi'
 include 'console-webapp'
 include 'jetty'
+include 'load-testing'