feat: user Vert.x as the default HttpClient implementation

Signed-off-by: Marc Nuri <marc@marcnuri.com>

Author: manusa

.github/workflows/e2e-httpclient-tests.yml

@@ -39,7 +39,7 @@ jobs:
       fail-fast: false
       matrix:
         kubernetes: [v1.28.1,v1.27.5]
-        httpclient: [jdk,jetty,vertx]
+        httpclient: [jdk,jetty,okhttp]
     steps:
       - name: Checkout
         uses: actions/checkout@v4

CHANGELOG.md

@@ -43,6 +43,7 @@
 * Fix #6158: Removed deprecated methods from `io.fabric8.kubernetes.client.utils.IOHelpers` class
 * Fix #6159: Removed deprecated `io.fabric8.kubernetes.client.utils.Utils.getPluralFromKind` method
 * Fix #6361: Renamed SettableBeanPropertyDelegate to SettableBeanPropertyDelegating
+* Fix #6470: Switched default HTTP client from OkHttp to Vert.x (`kubernetes-httpclient-vertx`)
 * Fix #6603: Removed deprecated `io.fabric8.openshift.api.model.runtime.RawExtension` class
 * Fix #6605: Removed deprecated `ApiVersionUtil` classes in extension modules
 * Fix #6609: Removed deprecated `io.fabric8.crd.generator.CRDInfo.getVersion` method

chaos-tests/pom.xml

@@ -49,13 +49,13 @@
       <exclusions>
         <exclusion>
           <groupId>io.fabric8</groupId>
-          <artifactId>kubernetes-httpclient-okhttp</artifactId>
+          <artifactId>kubernetes-httpclient-vertx</artifactId>
         </exclusion>
       </exclusions>
     </dependency>
     <dependency>
       <groupId>io.fabric8</groupId>
-      <artifactId>kubernetes-httpclient-okhttp</artifactId>
+      <artifactId>kubernetes-httpclient-vertx</artifactId>
       <scope>test</scope>
     </dependency>
 

doc/FAQ.md

@@ -2,6 +2,7 @@
 
 ## Contents
 - [Java baseline set to Java 11](#java-11)
+- [Vert.x as default HttpClient implementation](#vertx-httpclient)
 - [Bouncy Castle is no longer needed](#bouncy-castle)
 - [Config changes](#config-changes)
   - [Support for multiple kubeconfig files](#config-changes-multiple-kubeconfig)
@@ -41,6 +42,14 @@ Starting from version 7.0.0, you will need a Java 11+ runtime (using the latest
 It's been more than 10 years since Java 8 was released, and it's no longer supported by most vendors.
 We made our best effort to keep the client compatible with Java 8 for as long as possible, but it's time to move on.
 
+## Vert.x as default HttpClient implementation <a href="#vertx-httpclient" id="vertx-httpclient"/>
+
+OkHttp has been replaced by Vert.x as the default HttpClient implementation.
+As of version 7.0.0, the Fabric8 Kubernetes Client `io.fabric8:kubernetes-client` and `io.fabric8:openshift-client` include a transitive dependency to the `io.fabric8:kubernetes-httpclient-vertx` module.
+
+If you want to continue using OkHttp as the HttpClient, you can do so by adding the `io.fabric8:kubernetes-httpclient-okhttp` module as a dependency.
+It is also recommended (although not mandatory) to add an exclusion for the `io.fabric8:kubernetes-httpclient-vertx` module to avoid having both implementations in the classpath.
+
 ## Bouncy Castle is no longer needed <a href="#bouncy-castle" id="bouncy-castle"/>
 
 The Bouncy Castle library is no longer needed as a dependency.

doc/MIGRATION-v7.md

@@ -67,7 +67,7 @@
     </dependency>
     <dependency>
       <groupId>io.fabric8</groupId>
-      <artifactId>kubernetes-httpclient-okhttp</artifactId>
+      <artifactId>kubernetes-httpclient-vertx</artifactId>
       <scope>runtime</scope>
     </dependency>
 
@@ -205,7 +205,7 @@
             </goals>
             <configuration>
               <excludeDependencies>
-                kubernetes-httpclient-okhttp
+                kubernetes-httpclient-vertx
               </excludeDependencies>
               <instructions>
                 <Bundle-Name>${project.name}</Bundle-Name>

kubernetes-client/pom.xml

@@ -102,7 +102,7 @@
           <exclusions>
             <exclusion>
               <groupId>io.fabric8</groupId>
-              <artifactId>kubernetes-httpclient-okhttp</artifactId>
+              <artifactId>kubernetes-httpclient-vertx</artifactId>
             </exclusion>
           </exclusions>
         </dependency>
@@ -122,7 +122,7 @@
           <exclusions>
             <exclusion>
               <groupId>io.fabric8</groupId>
-              <artifactId>kubernetes-httpclient-okhttp</artifactId>
+              <artifactId>kubernetes-httpclient-vertx</artifactId>
             </exclusion>
           </exclusions>
         </dependency>
@@ -133,7 +133,7 @@
       </dependencies>
     </profile>
     <profile>
-      <id>httpclient-vertx</id>
+      <id>httpclient-okhttp</id>
       <dependencies>
         <dependency>
           <groupId>io.fabric8</groupId>
@@ -142,13 +142,13 @@
           <exclusions>
             <exclusion>
               <groupId>io.fabric8</groupId>
-              <artifactId>kubernetes-httpclient-okhttp</artifactId>
+              <artifactId>kubernetes-httpclient-vertx</artifactId>
             </exclusion>
           </exclusions>
         </dependency>
         <dependency>
           <groupId>io.fabric8</groupId>
-          <artifactId>kubernetes-httpclient-vertx</artifactId>
+          <artifactId>kubernetes-httpclient-okhttp</artifactId>
         </dependency>
       </dependencies>
     </profile>

kubernetes-itests/pom.xml

@@ -74,6 +74,7 @@
 import java.util.function.Function;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
 import static org.awaitility.Awaitility.await;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
@@ -103,7 +104,7 @@ class DefaultSharedIndexInformerTest {
       .withKind("Animal")
       .withScope("Namespaced")
       .build();
-  private KubernetesClient client;
+  KubernetesClient client;
   private SharedInformerFactory factory;
 
   @BeforeEach
@@ -212,7 +213,7 @@ void testInformerWithNamespaceAndNameConfigured() throws InterruptedException {
             RESYNC_PERIOD);
     CountDownLatch foundExistingPod = new CountDownLatch(1);
     podInformer.addEventHandler(
-        new ResourceEventHandler<Pod>() {
+        new ResourceEventHandler<>() {
           @Override
           public void onAdd(Pod obj) {
             if (obj.getMetadata().getName().equalsIgnoreCase("pod1")) {
@@ -541,7 +542,7 @@ void testEventListeners() throws InterruptedException {
     SharedIndexInformer<Pod> podInformer = factory.sharedIndexInformerFor(Pod.class, 1000L);
     CountDownLatch failureCallbackReceived = new CountDownLatch(1);
     podInformer.addEventHandler(
-        new ResourceEventHandler<Pod>() {
+        new ResourceEventHandler<>() {
           @Override
           public void onAdd(Pod obj) {
           }
@@ -1224,22 +1225,19 @@ void testClientStopClosesInformer() throws InterruptedException {
   }
 
   @Test
-  void testClientStopClosesInformerBeforeStarting() throws InterruptedException {
+  void clientStopPreventsInformerFromStarting() {
     // Given
     setupMockServerExpectations(Animal.class, "ns1", this::getList,
         r -> new WatchEvent(getAnimal("red-panda", "Carnivora", r), "ADDED"), null, null);
-
-    // When
     SharedIndexInformer<GenericKubernetesResource> animalSharedIndexInformer = client
         .genericKubernetesResources(animalContext)
         .inNamespace("ns1")
         .runnableInformer(60 * WATCH_EVENT_EMIT_TIME);
-
     client.close();
-
-    animalSharedIndexInformer.start();
-
-    assertTrue(animalSharedIndexInformer.stopped().toCompletableFuture().isDone());
+    // When
+    assertThatIllegalStateException()
+        .isThrownBy(animalSharedIndexInformer::start)
+        .withMessage("Client is closed");
   }
 
   private KubernetesResource getAnimal(String name, String order, String resourceVersion) {

kubernetes-tests/src/test/java/io/fabric8/kubernetes/client/mock/DefaultSharedIndexInformerTest.java

@@ -46,7 +46,6 @@
 import io.fabric8.kubernetes.client.utils.InputStreamPumper;
 import io.fabric8.kubernetes.client.utils.Utils;
 import io.fabric8.mockwebserver.internal.WebSocketMessage;
-import okio.ByteString;
 import org.awaitility.Awaitility;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
@@ -830,7 +829,7 @@ void testPortForward() throws IOException {
       } while (read >= 0);
       buffer.flip();
       channel.socket().close();
-      assertEquals("Hello World", ByteString.of(buffer).utf8());
+      assertEquals("Hello World", StandardCharsets.UTF_8.decode(buffer).toString());
       assertFalse(portForward.errorOccurred());
       assertEquals(0, portForward.getClientThrowables().size());
       assertEquals(0, portForward.getServerThrowables().size());

kubernetes-tests/src/test/java/io/fabric8/kubernetes/client/mock/PodTest.java

@@ -166,6 +166,10 @@ public class KubernetesLookup extends AbstractLookup {
       .isClassAvailable("org.apache.logging.log4j.spring.cloud.config.client.SpringEnvironmentHolder")
       || LoaderUtil.isClassAvailable("org.apache.logging.log4j.spring.boot.SpringEnvironmentHolder");
 
+  // Vert.x uses Log4j as a logger, if the KubernetesLookup info is initialized when the plugin is instantiated
+  // it will cause an infinite loop since the Log4j factory will invoke the KubernetesLookup plugin,
+  // the Vert.x client will invoke the Log4j factory again, and so forth.
+  private volatile boolean initialized;
   private Pod pod;
   private Namespace namespace;
   private URL masterUrl;
@@ -177,14 +181,14 @@ public KubernetesLookup() {
     this.pod = null;
     this.namespace = null;
     this.masterUrl = null;
-    initialize(this);
+    this.initialized = false;
   }
 
   KubernetesLookup(Pod pod, Namespace namespace, URL masterUrl) {
     this.pod = pod;
     this.namespace = namespace;
     this.masterUrl = masterUrl;
-    initialize(this);
+    this.initialized = false;
   }
 
   private static void initialize(KubernetesLookup lookup) {
@@ -252,7 +256,7 @@ private static void tryInitializeFields(KubernetesLookup lookup) {
    * <p>
    * Used in tests to provide a mock client.
    * </p>
-   * 
+   *
    * @return A Kubernetes client.
    */
   protected KubernetesClient createClient() {
@@ -370,6 +374,12 @@ private static Container getContainer(PodSpec podSpec, String containerName) {
 
   @Override
   public String lookup(final LogEvent event, final String key) {
+    synchronized (this) {
+      if (!initialized) {
+        initialize(this);
+        initialized = true;
+      }
+    }
     KubernetesInfo info;
     READ_LOCK.lock();
     try {