From 738717ef5201354092c6e8c4ea1e691d3913cab7 Mon Sep 17 00:00:00 2001
From: Gian Merlino <gianmerlino@gmail.com>
Date: Mon, 14 Apr 2025 23:01:48 -0700
Subject: [PATCH 1/7] k8s: Update fabric8 to 6.13.1, switch to Vert.x http
 client.

fabric8 6.x uses the OkHttp client by default, which itself uses an
unbounded-size cached pool, with 60s timeout, for making requests.
In production with large task counts, this leads to lots of thread churn.

The Vert.x client is the default in fabric8 7.x, and is better behaved.
By default it uses a worker pool of 20 threads (see javadoc for VertxOptions).

This patch uses fabric8 6.13.1 rather than some later version, because
higher versions are not compatible with Jackson 2.12.
---
 .../kubernetes-overlord-extensions/pom.xml    | 28 +++++++++++++++----
 .../common/DruidKubernetesClient.java         | 21 ++++++--------
 .../KubernetesTaskRunnerFactoryTest.java      |  3 +-
 .../DruidPeonClientIntegrationTest.java       |  3 +-
 4 files changed, 36 insertions(+), 19 deletions(-)

diff --git a/extensions-core/kubernetes-overlord-extensions/pom.xml b/extensions-core/kubernetes-overlord-extensions/pom.xml
index eb2fc63f8b2f..ba2e213f6d3b 100644
--- a/extensions-core/kubernetes-overlord-extensions/pom.xml
+++ b/extensions-core/kubernetes-overlord-extensions/pom.xml
@@ -34,6 +34,13 @@
     <relativePath>../../pom.xml</relativePath>
   </parent>
 
+  <properties>
+    <!-- fabric8 6.13.2+ is incompatible with jackson 2.12
+       ~ due to fix for https://github.com/fabric8io/kubernetes-client/issues/6110.
+       ~ GoIntegerDeserializer uses a _parseInteger method that does not exist in 2.12 (introduced in 2.14) -->
+    <fabric8.version>6.13.1</fabric8.version>
+  </properties>
+
   <dependencyManagement>
       <dependencies>
             <!-- snakeyaml explicitly pinned to version 1.33 as it is
@@ -111,7 +118,7 @@
     <dependency>
       <groupId>io.fabric8</groupId>
       <artifactId>kubernetes-model-core</artifactId>
-      <version>6.7.2</version>
+      <version>${fabric8.version}</version>
     </dependency>
     <dependency>
       <groupId>jakarta.validation</groupId>
@@ -121,18 +128,29 @@
     <dependency>
       <groupId>io.fabric8</groupId>
       <artifactId>kubernetes-model-batch</artifactId>
-      <version>6.7.2</version>
+      <version>${fabric8.version}</version>
     </dependency>
     <dependency>
       <groupId>io.fabric8</groupId>
       <artifactId>kubernetes-client-api</artifactId>
-      <version>6.7.2</version>
+      <version>${fabric8.version}</version>
     </dependency>
     <dependency>
       <groupId>io.fabric8</groupId>
       <artifactId>kubernetes-client</artifactId>
-      <version>6.7.2</version>
+      <version>${fabric8.version}</version>
       <scope>runtime</scope>
+      <exclusions>
+        <exclusion>
+          <groupId>io.fabric8</groupId>
+          <artifactId>kubernetes-httpclient-okhttp</artifactId>
+        </exclusion>
+      </exclusions>
+    </dependency>
+    <dependency>
+      <groupId>io.fabric8</groupId>
+      <artifactId>kubernetes-httpclient-vertx</artifactId>
+      <version>${fabric8.version}</version>
     </dependency>
     <dependency>
       <groupId>javax.ws.rs</groupId>
@@ -169,7 +187,7 @@
     <dependency>
       <groupId>io.fabric8</groupId>
       <artifactId>kubernetes-server-mock</artifactId>
-      <version>6.4.1</version>
+      <version>${fabric8.version}</version>
       <scope>test</scope>
     </dependency>
     <dependency>
diff --git a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesClient.java b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesClient.java
index f1f81bed8d8d..9106cab321c0 100644
--- a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesClient.java
+++ b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesClient.java
@@ -20,25 +20,20 @@
 package org.apache.druid.k8s.overlord.common;
 
 import io.fabric8.kubernetes.client.Config;
-import io.fabric8.kubernetes.client.ConfigBuilder;
 import io.fabric8.kubernetes.client.KubernetesClient;
 import io.fabric8.kubernetes.client.KubernetesClientBuilder;
+import io.fabric8.kubernetes.client.vertx.VertxHttpClientFactory;
 
 public class DruidKubernetesClient implements KubernetesClientApi
 {
-
-  private final Config config;
   private final KubernetesClient kubernetesClient;
 
-  public DruidKubernetesClient()
-  {
-    this(new ConfigBuilder().build());
-  }
-
-  public DruidKubernetesClient(Config config)
+  public DruidKubernetesClient(Config kubernetesClientConfig)
   {
-    this.config = config;
-    this.kubernetesClient = new KubernetesClientBuilder().withConfig(config).build();
+    this.kubernetesClient = new KubernetesClientBuilder()
+        .withHttpClientFactory(new VertxHttpClientFactory())
+        .withConfig(kubernetesClientConfig)
+        .build();
   }
 
   @Override
@@ -47,8 +42,10 @@ public <T> T executeRequest(KubernetesExecutor<T> executor) throws KubernetesRes
     return executor.executeRequest(kubernetesClient);
   }
 
-  /** This client automatically gets closed by the druid lifecycle, it should not be closed when used as it is
+  /**
+   * This client automatically gets closed by the druid lifecycle, it should not be closed when used as it is
    * meant to be reused.
+   *
    * @return re-useable KubernetesClient
    */
   @Override
diff --git a/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/KubernetesTaskRunnerFactoryTest.java b/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/KubernetesTaskRunnerFactoryTest.java
index d12aae08a55f..db7f86e852f4 100644
--- a/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/KubernetesTaskRunnerFactoryTest.java
+++ b/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/KubernetesTaskRunnerFactoryTest.java
@@ -21,6 +21,7 @@
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 import io.fabric8.kubernetes.api.model.batch.v1.Job;
+import io.fabric8.kubernetes.client.ConfigBuilder;
 import org.apache.druid.indexing.common.TestUtils;
 import org.apache.druid.indexing.common.task.Task;
 import org.apache.druid.java.util.emitter.service.ServiceEmitter;
@@ -54,7 +55,7 @@ public void setup()
         .withCapacity(1)
         .build();
     taskLogs = new NoopTaskLogs();
-    druidKubernetesClient = new DruidKubernetesClient();
+    druidKubernetesClient = new DruidKubernetesClient(new ConfigBuilder().build());
     taskAdapter = new TestTaskAdapter();
   }
 
diff --git a/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/taskadapter/DruidPeonClientIntegrationTest.java b/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/taskadapter/DruidPeonClientIntegrationTest.java
index cd865e256ee5..6c61121db299 100644
--- a/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/taskadapter/DruidPeonClientIntegrationTest.java
+++ b/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/taskadapter/DruidPeonClientIntegrationTest.java
@@ -24,6 +24,7 @@
 import io.fabric8.kubernetes.api.model.Pod;
 import io.fabric8.kubernetes.api.model.PodSpec;
 import io.fabric8.kubernetes.api.model.batch.v1.Job;
+import io.fabric8.kubernetes.client.ConfigBuilder;
 import org.apache.commons.io.FileUtils;
 import org.apache.commons.io.IOUtils;
 import org.apache.druid.indexing.common.TestUtils;
@@ -85,7 +86,7 @@ public void setup()
         new NamedType(ParallelIndexTuningConfig.class, "index_parallel"),
         new NamedType(IndexTask.IndexTuningConfig.class, "index")
     );
-    k8sClient = new DruidKubernetesClient();
+    k8sClient = new DruidKubernetesClient(new ConfigBuilder().build());
     peonClient = new KubernetesPeonClient(k8sClient, "default", false, new NoopServiceEmitter());
     druidNode = new DruidNode(
         "test",

From 16dd1d65e1a5c2f6e274f5fcc1b83b0dc41def2d Mon Sep 17 00:00:00 2001
From: Gian Merlino <gianmerlino@gmail.com>
Date: Mon, 14 Apr 2025 23:03:52 -0700
Subject: [PATCH 2/7] Fix call.

---
 .../druid/k8s/overlord/KubernetesOverlordModule.java   | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/KubernetesOverlordModule.java b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/KubernetesOverlordModule.java
index 1b07a34b43c8..35967abdd9cd 100644
--- a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/KubernetesOverlordModule.java
+++ b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/KubernetesOverlordModule.java
@@ -125,16 +125,16 @@ public void configure(Binder binder)
   @LazySingleton
   public DruidKubernetesClient makeKubernetesClient(KubernetesTaskRunnerConfig kubernetesTaskRunnerConfig, Lifecycle lifecycle)
   {
-    DruidKubernetesClient client;
+    final DruidKubernetesClient client;
+    final Config config = new ConfigBuilder().build();
+
     if (kubernetesTaskRunnerConfig.isDisableClientProxy()) {
-      Config config = new ConfigBuilder().build();
       config.setHttpsProxy(null);
       config.setHttpProxy(null);
-      client = new DruidKubernetesClient(config);
-    } else {
-      client = new DruidKubernetesClient();
     }
 
+    client = new DruidKubernetesClient(config);
+
     lifecycle.addHandler(
         new Lifecycle.Handler()
         {

From ba9666af8debccc7dcc897801bf14bca00adabbc Mon Sep 17 00:00:00 2001
From: Gian Merlino <gianmerlino@gmail.com>
Date: Tue, 15 Apr 2025 00:05:27 -0700
Subject: [PATCH 3/7] Update licenses.yaml. Override thread pool configs.

---
 .../overlord/KubernetesOverlordModule.java    | 12 ++-
 .../common/DruidKubernetesClient.java         |  5 +-
 .../DruidKubernetesHttpClientConfig.java      | 53 ++++++++++++
 .../DruidKubernetesHttpClientFactory.java     | 82 +++++++++++++++++++
 .../KubernetesTaskRunnerFactoryTest.java      |  4 +-
 .../DruidPeonClientIntegrationTest.java       |  3 +-
 licenses.yaml                                 | 16 +++-
 7 files changed, 166 insertions(+), 9 deletions(-)
 create mode 100644 extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java
 create mode 100644 extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientFactory.java

diff --git a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/KubernetesOverlordModule.java b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/KubernetesOverlordModule.java
index 35967abdd9cd..6320eb7df20a 100644
--- a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/KubernetesOverlordModule.java
+++ b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/KubernetesOverlordModule.java
@@ -57,6 +57,7 @@
 import org.apache.druid.java.util.common.lifecycle.Lifecycle;
 import org.apache.druid.java.util.common.logger.Logger;
 import org.apache.druid.k8s.overlord.common.DruidKubernetesClient;
+import org.apache.druid.k8s.overlord.common.DruidKubernetesHttpClientConfig;
 import org.apache.druid.k8s.overlord.execution.KubernetesTaskExecutionConfigResource;
 import org.apache.druid.k8s.overlord.execution.KubernetesTaskRunnerDynamicConfig;
 import org.apache.druid.k8s.overlord.runnerstrategy.RunnerStrategy;
@@ -85,6 +86,7 @@ public class KubernetesOverlordModule implements DruidModule
                                                                + ".k8sAndWorker";
   private static final String RUNNERSTRATEGY_PROPERTIES_FORMAT_STRING = K8SANDWORKER_PROPERTIES_PREFIX
                                                                         + ".runnerStrategy.%s";
+  private static final String HTTPCLIENT_PROPERITES_PREFIX = K8SANDWORKER_PROPERTIES_PREFIX + ".http";
 
   @Override
   public void configure(Binder binder)
@@ -119,11 +121,17 @@ public void configure(Binder binder)
     configureTaskLogs(binder);
 
     Jerseys.addResource(binder, KubernetesTaskExecutionConfigResource.class);
+
+    JsonConfigProvider.bind(binder, HTTPCLIENT_PROPERITES_PREFIX, DruidKubernetesHttpClientConfig.class);
   }
 
   @Provides
   @LazySingleton
-  public DruidKubernetesClient makeKubernetesClient(KubernetesTaskRunnerConfig kubernetesTaskRunnerConfig, Lifecycle lifecycle)
+  public DruidKubernetesClient makeKubernetesClient(
+      KubernetesTaskRunnerConfig kubernetesTaskRunnerConfig,
+      DruidKubernetesHttpClientConfig httpClientConfig,
+      Lifecycle lifecycle
+  )
   {
     final DruidKubernetesClient client;
     final Config config = new ConfigBuilder().build();
@@ -133,7 +141,7 @@ public DruidKubernetesClient makeKubernetesClient(KubernetesTaskRunnerConfig kub
       config.setHttpProxy(null);
     }
 
-    client = new DruidKubernetesClient(config);
+    client = new DruidKubernetesClient(httpClientConfig, config);
 
     lifecycle.addHandler(
         new Lifecycle.Handler()
diff --git a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesClient.java b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesClient.java
index 9106cab321c0..9c1940bb1f44 100644
--- a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesClient.java
+++ b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesClient.java
@@ -22,16 +22,15 @@
 import io.fabric8.kubernetes.client.Config;
 import io.fabric8.kubernetes.client.KubernetesClient;
 import io.fabric8.kubernetes.client.KubernetesClientBuilder;
-import io.fabric8.kubernetes.client.vertx.VertxHttpClientFactory;
 
 public class DruidKubernetesClient implements KubernetesClientApi
 {
   private final KubernetesClient kubernetesClient;
 
-  public DruidKubernetesClient(Config kubernetesClientConfig)
+  public DruidKubernetesClient(DruidKubernetesHttpClientConfig httpClientConfig, Config kubernetesClientConfig)
   {
     this.kubernetesClient = new KubernetesClientBuilder()
-        .withHttpClientFactory(new VertxHttpClientFactory())
+        .withHttpClientFactory(new DruidKubernetesHttpClientFactory(httpClientConfig))
         .withConfig(kubernetesClientConfig)
         .build();
   }
diff --git a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java
new file mode 100644
index 000000000000..0fbaa793421e
--- /dev/null
+++ b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java
@@ -0,0 +1,53 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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 org.apache.druid.k8s.overlord.common;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+import io.vertx.core.VertxOptions;
+
+import javax.validation.constraints.Min;
+
+public class DruidKubernetesHttpClientConfig
+{
+  @JsonProperty
+  private int workerPoolSize = VertxOptions.DEFAULT_WORKER_POOL_SIZE;
+
+  @JsonProperty
+  @Min(1)
+  private int eventLoopPoolSize = VertxOptions.DEFAULT_EVENT_LOOP_POOL_SIZE;
+
+  @JsonProperty
+  private int internalBlockingPoolSize = VertxOptions.DEFAULT_INTERNAL_BLOCKING_POOL_SIZE;
+
+  public int getWorkerPoolSize()
+  {
+    return workerPoolSize;
+  }
+
+  public int getEventLoopPoolSize()
+  {
+    return eventLoopPoolSize;
+  }
+
+  public int getInternalBlockingPoolSize()
+  {
+    return internalBlockingPoolSize;
+  }
+}
diff --git a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientFactory.java b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientFactory.java
new file mode 100644
index 000000000000..1924eb11d819
--- /dev/null
+++ b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientFactory.java
@@ -0,0 +1,82 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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 org.apache.druid.k8s.overlord.common;
+
+import io.fabric8.kubernetes.client.http.HttpClient;
+import io.fabric8.kubernetes.client.vertx.VertxHttpClientBuilder;
+import io.fabric8.kubernetes.client.vertx.VertxHttpClientFactory;
+import io.vertx.core.Vertx;
+import io.vertx.core.VertxOptions;
+import io.vertx.core.file.FileSystemOptions;
+import io.vertx.core.spi.resolver.ResolverProvider;
+
+/**
+ * Similar to {@link VertxHttpClientFactory} but allows us to override thread pool configurations.
+ */
+public class DruidKubernetesHttpClientFactory implements HttpClient.Factory
+{
+  private final Vertx vertx;
+
+  public DruidKubernetesHttpClientFactory(final DruidKubernetesHttpClientConfig httpClientConfig)
+  {
+    this.vertx = createVertxInstance(httpClientConfig);
+  }
+
+  @Override
+  public VertxHttpClientBuilder<DruidKubernetesHttpClientFactory> newBuilder()
+  {
+    return new VertxHttpClientBuilder<>(this, vertx);
+  }
+
+  /**
+   * Adapted from fabric8 kubernetes-client 7.1.0. We bring this here so we can customize thread pool sizes
+   * and force usage of daemon threads.
+   */
+  private static Vertx createVertxInstance(final DruidKubernetesHttpClientConfig httpClientConfig)
+  {
+    // fabric8 disables the async DNS resolver while creating Vertx.
+    // I'm not sure if we really need to do this, but I'm keeping it to align behavior with upstream.
+    final String originalDnsResolverProperty = System.getProperty(ResolverProvider.DISABLE_DNS_RESOLVER_PROP_NAME);
+    Vertx vertx;
+    try {
+      System.setProperty(ResolverProvider.DISABLE_DNS_RESOLVER_PROP_NAME, "true");
+      vertx = Vertx.vertx(
+          new VertxOptions()
+              .setFileSystemOptions(
+                  new FileSystemOptions().setFileCachingEnabled(false)
+                                         .setClassPathResolvingEnabled(false)
+              )
+              .setWorkerPoolSize(httpClientConfig.getWorkerPoolSize())
+              .setEventLoopPoolSize(httpClientConfig.getEventLoopPoolSize())
+              .setInternalBlockingPoolSize(httpClientConfig.getInternalBlockingPoolSize())
+              .setUseDaemonThread(true)
+      );
+    }
+    finally {
+      if (originalDnsResolverProperty == null) {
+        System.clearProperty(ResolverProvider.DISABLE_DNS_RESOLVER_PROP_NAME);
+      } else {
+        System.setProperty(ResolverProvider.DISABLE_DNS_RESOLVER_PROP_NAME, originalDnsResolverProperty);
+      }
+    }
+
+    return vertx;
+  }
+}
diff --git a/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/KubernetesTaskRunnerFactoryTest.java b/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/KubernetesTaskRunnerFactoryTest.java
index db7f86e852f4..49720642216f 100644
--- a/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/KubernetesTaskRunnerFactoryTest.java
+++ b/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/KubernetesTaskRunnerFactoryTest.java
@@ -26,6 +26,7 @@
 import org.apache.druid.indexing.common.task.Task;
 import org.apache.druid.java.util.emitter.service.ServiceEmitter;
 import org.apache.druid.k8s.overlord.common.DruidKubernetesClient;
+import org.apache.druid.k8s.overlord.common.DruidKubernetesHttpClientConfig;
 import org.apache.druid.k8s.overlord.common.K8sTaskId;
 import org.apache.druid.k8s.overlord.taskadapter.TaskAdapter;
 import org.apache.druid.tasklogs.NoopTaskLogs;
@@ -55,7 +56,8 @@ public void setup()
         .withCapacity(1)
         .build();
     taskLogs = new NoopTaskLogs();
-    druidKubernetesClient = new DruidKubernetesClient(new ConfigBuilder().build());
+    druidKubernetesClient =
+        new DruidKubernetesClient(new DruidKubernetesHttpClientConfig(), new ConfigBuilder().build());
     taskAdapter = new TestTaskAdapter();
   }
 
diff --git a/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/taskadapter/DruidPeonClientIntegrationTest.java b/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/taskadapter/DruidPeonClientIntegrationTest.java
index 6c61121db299..446c2502fa11 100644
--- a/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/taskadapter/DruidPeonClientIntegrationTest.java
+++ b/extensions-core/kubernetes-overlord-extensions/src/test/java/org/apache/druid/k8s/overlord/taskadapter/DruidPeonClientIntegrationTest.java
@@ -35,6 +35,7 @@
 import org.apache.druid.indexing.common.task.batch.parallel.ParallelIndexTuningConfig;
 import org.apache.druid.k8s.overlord.KubernetesTaskRunnerConfig;
 import org.apache.druid.k8s.overlord.common.DruidKubernetesClient;
+import org.apache.druid.k8s.overlord.common.DruidKubernetesHttpClientConfig;
 import org.apache.druid.k8s.overlord.common.JobResponse;
 import org.apache.druid.k8s.overlord.common.K8sTaskId;
 import org.apache.druid.k8s.overlord.common.K8sTestUtils;
@@ -86,7 +87,7 @@ public void setup()
         new NamedType(ParallelIndexTuningConfig.class, "index_parallel"),
         new NamedType(IndexTask.IndexTuningConfig.class, "index")
     );
-    k8sClient = new DruidKubernetesClient(new ConfigBuilder().build());
+    k8sClient = new DruidKubernetesClient(new DruidKubernetesHttpClientConfig(), new ConfigBuilder().build());
     peonClient = new KubernetesPeonClient(k8sClient, "default", false, new NoopServiceEmitter());
     druidNode = new DruidNode(
         "test",
diff --git a/licenses.yaml b/licenses.yaml
index eb47a93aadaf..0927f5ac4353 100644
--- a/licenses.yaml
+++ b/licenses.yaml
@@ -855,7 +855,7 @@ name: kubernetes fabric java client
 license_category: binary
 module: extensions-core/kubernetes-overlord-extensions
 license_name: Apache License version 2.0
-version: 6.7.2
+version: 6.13.1
 libraries:
   - io.fabric8: kubernetes-client-api
   - io.fabric8: kubernetes-model-batch
@@ -882,6 +882,18 @@ libraries:
   - io.fabric8: kubernetes-model-storageclass
 ---
 
+name: vertx
+license_category: binary
+module: extensions-core/kubernetes-overlord-extensions
+license_name: Apache License version 2.0
+version: 4.5.8
+libraries:
+  - io.vertx: vertx-auth-common
+  - io.vertx: vertx-core
+  - io.vertx: vertx-web-client
+  - io.vertx: vertx-web-common
+---
+
 name: kubernetes official java client
 license_category: binary
 module: extensions/druid-kubernetes-extensions
@@ -1051,7 +1063,7 @@ name: org.snakeyaml snakeyaml-engine
 license_category: binary
 module: extensions-core/druid-kubernetes-overlord-extensions
 license_name: Apache License version 2.0
-version: 2.6
+version: 2.7
 libraries:
   - org.snakeyaml: snakeyaml-engine
 

From f8523dc0b22c9dbb51157b8f6f6f37b13a61c626 Mon Sep 17 00:00:00 2001
From: Gian Merlino <gianmerlino@gmail.com>
Date: Tue, 15 Apr 2025 00:06:23 -0700
Subject: [PATCH 4/7] Remove annotation.

---
 .../k8s/overlord/common/DruidKubernetesHttpClientConfig.java     | 1 -
 1 file changed, 1 deletion(-)

diff --git a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java
index 0fbaa793421e..6e48f6595836 100644
--- a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java
+++ b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java
@@ -30,7 +30,6 @@ public class DruidKubernetesHttpClientConfig
   private int workerPoolSize = VertxOptions.DEFAULT_WORKER_POOL_SIZE;
 
   @JsonProperty
-  @Min(1)
   private int eventLoopPoolSize = VertxOptions.DEFAULT_EVENT_LOOP_POOL_SIZE;
 
   @JsonProperty

From 9abe95d677e9302525e9f633d0e0f39e3ba4deb4 Mon Sep 17 00:00:00 2001
From: Gian Merlino <gianmerlino@gmail.com>
Date: Tue, 15 Apr 2025 00:50:12 -0700
Subject: [PATCH 5/7] Fix style.

---
 .../k8s/overlord/common/DruidKubernetesHttpClientConfig.java    | 2 --
 1 file changed, 2 deletions(-)

diff --git a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java
index 6e48f6595836..b659f8e9af50 100644
--- a/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java
+++ b/extensions-core/kubernetes-overlord-extensions/src/main/java/org/apache/druid/k8s/overlord/common/DruidKubernetesHttpClientConfig.java
@@ -22,8 +22,6 @@
 import com.fasterxml.jackson.annotation.JsonProperty;
 import io.vertx.core.VertxOptions;
 
-import javax.validation.constraints.Min;
-
 public class DruidKubernetesHttpClientConfig
 {
   @JsonProperty

From d841de1d8d9db910844abb7219cbce0cfe028fa2 Mon Sep 17 00:00:00 2001
From: Gian Merlino <gianmerlino@gmail.com>
Date: Tue, 15 Apr 2025 01:26:54 -0700
Subject: [PATCH 6/7] Update licenses.yaml.

---
 licenses.yaml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/licenses.yaml b/licenses.yaml
index 0927f5ac4353..33c09795182f 100644
--- a/licenses.yaml
+++ b/licenses.yaml
@@ -880,6 +880,7 @@ libraries:
   - io.fabric8: kubernetes-model-resource
   - io.fabric8: kubernetes-model-scheduling
   - io.fabric8: kubernetes-model-storageclass
+  - io.fabric8: kubernetes-httpclient-vertx
 ---
 
 name: vertx

From 9723ec311146b327f9714ff7ebf1ea3fcfceeeae Mon Sep 17 00:00:00 2001
From: Gian Merlino <gianmerlino@gmail.com>
Date: Tue, 15 Apr 2025 03:48:32 -0700
Subject: [PATCH 7/7] Add dep.

---
 extensions-core/kubernetes-overlord-extensions/pom.xml | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/extensions-core/kubernetes-overlord-extensions/pom.xml b/extensions-core/kubernetes-overlord-extensions/pom.xml
index ba2e213f6d3b..80e61cec9ee6 100644
--- a/extensions-core/kubernetes-overlord-extensions/pom.xml
+++ b/extensions-core/kubernetes-overlord-extensions/pom.xml
@@ -152,6 +152,11 @@
       <artifactId>kubernetes-httpclient-vertx</artifactId>
       <version>${fabric8.version}</version>
     </dependency>
+    <dependency>
+      <groupId>io.vertx</groupId>
+      <artifactId>vertx-core</artifactId>
+      <version>4.5.8</version>
+    </dependency>
     <dependency>
       <groupId>javax.ws.rs</groupId>
       <artifactId>jsr311-api</artifactId>