feat: @KubernetesTest/KubernetesNamespacedTestExtension creates an ep…

…hemeral Namespace optionally (can opt-out)

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

CHANGELOG.md

@@ -12,6 +12,7 @@
 * Fix #4694: [java-generator] Option to override the package name of the generated code.
 * Fix #4720: interceptors close any response body if the response is not a 2xx response.
 * Fix #4734: @KubernetesTest annotation can be used in base test classes
+* Fix #4734: @KubernetesTest creates an ephemeral Namespace optionally (can opt-out)
 
 #### Dependency Upgrade
 

junit/kubernetes-junit-jupiter/src/main/java/io/fabric8/junit/jupiter/BaseExtension.java

@@ -17,6 +17,7 @@
 
 import org.junit.jupiter.api.extension.ExtensionContext;
 
+import java.lang.annotation.Annotation;
 import java.lang.reflect.Field;
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -28,10 +29,12 @@
 
 public interface BaseExtension {
 
-  ExtensionContext.Namespace getNamespace();
+  default ExtensionContext.Namespace getNamespace(ExtensionContext context) {
+    return ExtensionContext.Namespace.create(context.getRequiredTestClass());
+  }
 
   default ExtensionContext.Store getStore(ExtensionContext context) {
-    return context.getRoot().getStore(getNamespace());
+    return context.getRoot().getStore(getNamespace(context));
   }
 
   default Field[] extractFields(ExtensionContext context, Class<?> clazz, Predicate<Field>... predicates) {
@@ -64,4 +67,15 @@ default void setFieldValue(Field field, Object entity, Object value) throws Ille
     field.setAccessible(isAccessible);
   }
 
+  default <T extends Annotation> T findAnnotation(Class<?> clazz, Class<T> annotation) {
+    if (clazz != null) {
+      if (clazz.isAnnotationPresent(annotation)) {
+        return clazz.getAnnotation(annotation);
+      } else if (clazz.getSuperclass() != null) {
+        return findAnnotation(clazz.getSuperclass(), annotation);
+      }
+    }
+    return null;
+  }
+
 }

junit/kubernetes-junit-jupiter/src/main/java/io/fabric8/junit/jupiter/KubernetesNamespacedTestExtension.java

@@ -15,6 +15,7 @@
  */
 package io.fabric8.junit.jupiter;
 
+import io.fabric8.junit.jupiter.api.KubernetesTest;
 import io.fabric8.kubernetes.api.model.Namespace;
 import io.fabric8.kubernetes.api.model.NamespaceBuilder;
 import io.fabric8.kubernetes.api.model.ObjectReference;
@@ -37,22 +38,20 @@
 public class KubernetesNamespacedTestExtension
     implements HasKubernetesClient, BeforeAllCallback, BeforeEachCallback, AfterAllCallback {
 
-  @Override
-  public ExtensionContext.Namespace getNamespace() {
-    return ExtensionContext.Namespace.create(KubernetesNamespacedTestExtension.class);
-  }
-
   @Override
   public void beforeAll(ExtensionContext context) throws Exception {
     final KubernetesClient client = new KubernetesClientBuilder().build();
-    getStore(context).put(Namespace.class, initNamespace(client));
-    getStore(context).put(KubernetesClient.class,
-        client.adapt(NamespacedKubernetesClient.class).inNamespace(getNamespace(context).getMetadata().getName()));
+    getStore(context).put(KubernetesClient.class, client);
+    if (shouldCreateNamespace(context)) {
+      getStore(context).put(Namespace.class, initNamespace(client));
+      getStore(context).put(KubernetesClient.class,
+          client.adapt(NamespacedKubernetesClient.class).inNamespace(getKubernetesNamespace(context).getMetadata().getName()));
+    }
     for (Field field : extractFields(context, KubernetesClient.class, f -> Modifier.isStatic(f.getModifiers()))) {
       setFieldValue(field, null, getClient(context).adapt((Class<Client>) field.getType()));
     }
     for (Field field : extractFields(context, Namespace.class, f -> Modifier.isStatic(f.getModifiers()))) {
-      setFieldValue(field, null, getNamespace(context));
+      setFieldValue(field, null, getKubernetesNamespace(context));
     }
   }
 
@@ -62,14 +61,19 @@ public void beforeEach(ExtensionContext context) throws Exception {
       setFieldValue(field, context.getRequiredTestInstance(), getClient(context).adapt((Class<Client>) field.getType()));
     }
     for (Field field : extractFields(context, Namespace.class, f -> !Modifier.isStatic(f.getModifiers()))) {
-      setFieldValue(field, context.getRequiredTestInstance(), getNamespace(context));
+      setFieldValue(field, context.getRequiredTestInstance(), getKubernetesNamespace(context));
     }
   }
 
   @Override
   public void afterAll(ExtensionContext context) {
     final KubernetesClient client = getClient(context);
-    client.resource(getNamespace(context)).withGracePeriod(0L).delete();
+    if (shouldCreateNamespace(context)) {
+      client.resource(getKubernetesNamespace(context)).withGracePeriod(0L).delete();
+    }
+    // Note that the ThreadPoolExecutor in OkHttp's RealConnectionPool is shared amongst all the OkHttp client
+    // instances. This means that closing one OkHttp client instance effectively closes all the others.
+    // In order to be able to use this safely, we should transition to one of the other HttpClient implementations
     client.close();
   }
 
@@ -109,7 +113,12 @@ private static Namespace initNamespace(KubernetesClient client) {
     return namespace;
   }
 
-  private Namespace getNamespace(ExtensionContext context) {
+  private boolean shouldCreateNamespace(ExtensionContext context) {
+    final KubernetesTest annotation = findAnnotation(context.getRequiredTestClass(), KubernetesTest.class);
+    return annotation == null || annotation.createEphemeralNamespace();
+  }
+
+  private Namespace getKubernetesNamespace(ExtensionContext context) {
     final Namespace namespace = getStore(context).get(Namespace.class, Namespace.class);
     if (namespace == null) {
       throw new IllegalStateException("No Kubernetes Namespace found");

junit/kubernetes-junit-jupiter/src/main/java/io/fabric8/junit/jupiter/LoadKubernetesManifestsExtension.java

@@ -26,12 +26,6 @@
  */
 public class LoadKubernetesManifestsExtension implements HasKubernetesClient, BeforeAllCallback, AfterAllCallback {
 
-  @Override
-  public ExtensionContext.Namespace getNamespace() {
-    // Share context with KubernetesNamespacedTestExtension to be able to consume the client
-    return ExtensionContext.Namespace.create(KubernetesNamespacedTestExtension.class);
-  }
-
   @Override
   public void beforeAll(ExtensionContext context) {
     final LoadKubernetesManifests annotation = context.getRequiredTestClass()

junit/kubernetes-junit-jupiter/src/main/java/io/fabric8/junit/jupiter/api/KubernetesTest.java

@@ -31,9 +31,13 @@
  * Enables and configures the {@link KubernetesNamespacedTestExtension} extension.
  *
  * <p>
- * Creates a namespace and configures a {@link KubernetesClient} instance that will
+ * Creates a {@link KubernetesClient} instance that will
  * be automatically injected into tests.
  *
+ * <p>
+ * Optionally, creates a Namespace for the tests and configures the client to use it. The Namespace
+ * is deleted after the test suite execution.
+ *
  * <pre>{@code
  * &#64;KubernetesTest
  * class MyTest {
@@ -46,4 +50,8 @@
 @Retention(RUNTIME)
 @ExtendWith(KubernetesNamespacedTestExtension.class)
 public @interface KubernetesTest {
+  /**
+   * Create an ephemeral Namespace for the test.
+   */
+  boolean createEphemeralNamespace() default true;
 }

junit/kubernetes-junit-jupiter/src/main/java/io/fabric8/junit/jupiter/api/LoadKubernetesManifests.java

@@ -36,7 +36,8 @@
  */
 @Target({ TYPE, METHOD, ANNOTATION_TYPE })
 @Retention(RUNTIME)
-@ExtendWith({ KubernetesNamespacedTestExtension.class, LoadKubernetesManifestsExtension.class })
+@ExtendWith(KubernetesNamespacedTestExtension.class)
+@ExtendWith(LoadKubernetesManifestsExtension.class)
 public @interface LoadKubernetesManifests {
 
   String[] value();

junit/kubernetes-junit-jupiter/src/test/java/io/fabric8/junit/jupiter/api/KubernetesTestTest.java

@@ -21,7 +21,7 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-@KubernetesTest
+@KubernetesTest(createEphemeralNamespace = false)
 // Due to the way the extensions interact with the test, this test class can't be parameterized
 class KubernetesTestTest {
 

junit/kubernetes-junit-jupiter/src/test/java/io/fabric8/junit/jupiter/api/KubernetesTestWithSuperClass.java

@@ -17,7 +17,7 @@
 
 import io.fabric8.kubernetes.client.KubernetesClient;
 
-@KubernetesTest
+@KubernetesTest(createEphemeralNamespace = false)
 public class KubernetesTestWithSuperClass {
 
   static KubernetesClient staticSuperClient;