Controller name as finalizer by default

operator-framework/src/main/java/io/javaoperatorsdk/operator/ControllerUtils.java

@@ -24,15 +24,25 @@ public class ControllerUtils {
     private static Map<Class<? extends CustomResource>, Class<? extends CustomResourceDoneable<? extends CustomResource>>>
             doneableClassCache = new HashMap<>();
 
-    static String getDefaultFinalizer(ResourceController controller) {
-        return getAnnotation(controller).finalizerName();
+    static String getFinalizer(ResourceController controller) {
+        final String annotationFinalizerName = getAnnotation(controller).finalizerName();
+        final String finalizerName;
+        if (Controller.NULL.equals(annotationFinalizerName)) {
+            finalizerName = controller.getDefaultFinalizerName();
+            if (finalizerName == null) {
+                throw new IllegalStateException("Controller annotation cannot be used on Local, Anonymous or Hidden classes");
+            }
+        } else {
+            finalizerName = annotationFinalizerName;
+        }
+        return finalizerName;
     }
 
     static boolean getGenerationEventProcessing(ResourceController controller) {
         return getAnnotation(controller).generationAwareEventProcessing();
     }
 
-    static <R extends CustomResource> Class<R> getCustomResourceClass(ResourceController controller) {
+    static <R extends CustomResource> Class<R> getCustomResourceClass(ResourceController<R> controller) {
         return (Class<R>) getAnnotation(controller).customResourceClass();
     }
 

operator-framework/src/main/java/io/javaoperatorsdk/operator/Operator.java

@@ -55,7 +55,7 @@ private <R extends CustomResource> void registerController(ResourceController<R>
         Class<R> resClass = ControllerUtils.getCustomResourceClass(controller);
         CustomResourceDefinitionContext crd = getCustomResourceDefinitionForController(controller);
         KubernetesDeserializer.registerCustomKind(crd.getVersion(), crd.getKind(), resClass);
-        String finalizer = ControllerUtils.getDefaultFinalizer(controller);
+        String finalizer = ControllerUtils.getFinalizer(controller);
         MixedOperation client = k8sClient.customResources(crd, resClass, CustomResourceList.class, ControllerUtils.getCustomResourceDoneableClass(controller));
         EventDispatcher eventDispatcher = new EventDispatcher(controller,
                 finalizer, new EventDispatcher.CustomResourceFacade(client), ControllerUtils.getGenerationEventProcessing(controller));

operator-framework/src/main/java/io/javaoperatorsdk/operator/api/Controller.java

@@ -10,14 +10,17 @@
 @Retention(RetentionPolicy.RUNTIME)
 @Target({ElementType.TYPE})
 public @interface Controller {
-
-    String DEFAULT_FINALIZER = "operator.default.finalizer";
+    String NULL = "";
 
     String crdName();
 
     Class<? extends CustomResource> customResourceClass();
 
-    String finalizerName() default DEFAULT_FINALIZER;
+    /**
+     * Optional finalizer name, if it is not,
+     * the canonical name of the Controller class will be used as the name of the finalizer.
+     */
+    String finalizerName() default NULL;
 
     /**
      * If true, will dispatch new event to the controller if generation increased since the last processing, otherwise will

operator-framework/src/main/java/io/javaoperatorsdk/operator/api/ResourceController.java

@@ -28,4 +28,10 @@ public interface ResourceController<R extends CustomResource> {
      */
     UpdateControl<R> createOrUpdateResource(R resource, Context<R> context);
 
+    // What about we let developer to set the finalizer Name through overriding
+    // this method rather than setting it as attribute in annotation?
+    default String getDefaultFinalizerName() {
+        return this.getClass().getCanonicalName();
+    }
+
 }

operator-framework/src/test/java/io/javaoperatorsdk/operator/ControllerUtilsTest.java

@@ -1,9 +1,12 @@
 package io.javaoperatorsdk.operator;
 
-import io.javaoperatorsdk.operator.sample.TestCustomResource;
-import io.javaoperatorsdk.operator.sample.TestCustomResourceController;
 import io.fabric8.kubernetes.client.CustomResourceDoneable;
+import io.javaoperatorsdk.operator.api.Context;
 import io.javaoperatorsdk.operator.api.Controller;
+import io.javaoperatorsdk.operator.api.ResourceController;
+import io.javaoperatorsdk.operator.api.UpdateControl;
+import io.javaoperatorsdk.operator.sample.TestCustomResource;
+import io.javaoperatorsdk.operator.sample.TestCustomResourceController;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
@@ -12,12 +15,33 @@
 
 class ControllerUtilsTest {
 
+    public static final String CUSTOM_FINALIZER_NAME = "a.customer.finalizer";
+
     @Test
     public void returnsValuesFromControllerAnnotationFinalizer() {
-        Assertions.assertEquals(Controller.DEFAULT_FINALIZER, ControllerUtils.getDefaultFinalizer(new TestCustomResourceController(null)));
+        Assertions.assertEquals(TestCustomResourceController.class.getCanonicalName(), ControllerUtils.getFinalizer(new TestCustomResourceController(null)));
         assertEquals(TestCustomResource.class, ControllerUtils.getCustomResourceClass(new TestCustomResourceController(null)));
         Assertions.assertEquals(TestCustomResourceController.CRD_NAME, ControllerUtils.getCrdName(new TestCustomResourceController(null)));
         assertEquals(false, ControllerUtils.getGenerationEventProcessing(new TestCustomResourceController(null)));
         assertTrue(CustomResourceDoneable.class.isAssignableFrom(ControllerUtils.getCustomResourceDoneableClass(new TestCustomResourceController(null))));
     }
+
+    @Controller(crdName = "test.crd", customResourceClass = TestCustomResource.class, finalizerName = CUSTOM_FINALIZER_NAME)
+    static class TestCustomFinalizerController implements ResourceController<TestCustomResource> {
+
+        @Override
+        public boolean deleteResource(TestCustomResource resource, Context<TestCustomResource> context) {
+            return false;
+        }
+
+        @Override
+        public UpdateControl<TestCustomResource> createOrUpdateResource(TestCustomResource resource, Context<TestCustomResource> context) {
+            return null;
+        }
+    }
+
+    @Test
+    public void returnCustomerFinalizerNameIfSet() {
+        assertEquals(CUSTOM_FINALIZER_NAME, ControllerUtils.getFinalizer(new TestCustomFinalizerController()));
+    }
 }

operator-framework/src/test/java/io/javaoperatorsdk/operator/EventDispatcherTest.java

@@ -28,7 +28,7 @@ class EventDispatcherTest {
     @BeforeEach
     void setup() {
         eventDispatcher = new EventDispatcher(controller,
-                Controller.DEFAULT_FINALIZER, customResourceFacade, false);
+                controller.getDefaultFinalizerName(), customResourceFacade, false);
 
         testCustomResource = getResource();
 
@@ -45,7 +45,7 @@ void callCreateOrUpdateOnNewResource() {
 
     @Test
     void updatesOnlyStatusSubResource() {
-        testCustomResource.getMetadata().getFinalizers().add(Controller.DEFAULT_FINALIZER);
+        testCustomResource.getMetadata().getFinalizers().add(controller.getDefaultFinalizerName());
         when(controller.createOrUpdateResource(eq(testCustomResource), any()))
                 .thenReturn(UpdateControl.updateStatusSubResource(testCustomResource));
 
@@ -67,13 +67,13 @@ void adsDefaultFinalizerOnCreateIfNotThere() {
         eventDispatcher.handleEvent(customResourceEvent(Watcher.Action.MODIFIED, testCustomResource));
         verify(controller, times(1))
                 .createOrUpdateResource(argThat(testCustomResource ->
-                        testCustomResource.getMetadata().getFinalizers().contains(Controller.DEFAULT_FINALIZER)), any());
+                        testCustomResource.getMetadata().getFinalizers().contains(controller.getDefaultFinalizerName())), any());
     }
 
     @Test
     void callsDeleteIfObjectHasFinalizerAndMarkedForDelete() {
         testCustomResource.getMetadata().setDeletionTimestamp("2019-8-10");
-        testCustomResource.getMetadata().getFinalizers().add(Controller.DEFAULT_FINALIZER);
+        testCustomResource.getMetadata().getFinalizers().add(controller.getDefaultFinalizerName());
 
         eventDispatcher.handleEvent(customResourceEvent(Watcher.Action.MODIFIED, testCustomResource));
 
@@ -183,7 +183,7 @@ void doesNotMarkNewGenerationInCaseOfException() {
 
     void generationAwareMode() {
         eventDispatcher = new EventDispatcher(controller,
-                Controller.DEFAULT_FINALIZER, customResourceFacade, true);
+                controller.getDefaultFinalizerName(), customResourceFacade, true);
     }
 
     private void markForDeletion(CustomResource customResource) {
@@ -202,7 +202,7 @@ CustomResource getResource() {
                 .withDeletionGracePeriodSeconds(10L)
                 .withGeneration(10L)
                 .withName("name")
-                .withFinalizers(Controller.DEFAULT_FINALIZER)
+                .withFinalizers(controller.getDefaultFinalizerName())
                 .withNamespace("namespace")
                 .withResourceVersion("resourceVersion")
                 .withSelfLink("selfLink")

operator-framework/src/test/java/io/javaoperatorsdk/operator/SubResourceUpdateIT.java

@@ -104,7 +104,7 @@ public SubResourceTestCustomResource createTestCustomResource(String id) {
         resource.setMetadata(new ObjectMetaBuilder()
                 .withName("subresource-" + id)
                 .withNamespace(TEST_NAMESPACE)
-                .withFinalizers(Controller.DEFAULT_FINALIZER)
+                .withFinalizers("finalizer")
                 .build());
         resource.setKind("SubresourceSample");
         resource.setSpec(new SubResourceTestCustomResourceSpec());

operator-framework/src/test/java/io/javaoperatorsdk/operator/sample/TestCustomResourceController.java

@@ -55,7 +55,7 @@ public boolean deleteResource(TestCustomResource resource, Context<TestCustomRes
     public UpdateControl<TestCustomResource> createOrUpdateResource(TestCustomResource resource,
                                                                     Context<TestCustomResource> context) {
         numberOfExecutions.addAndGet(1);
-        if (!resource.getMetadata().getFinalizers().contains(Controller.DEFAULT_FINALIZER)) {
+        if (!resource.getMetadata().getFinalizers().contains(this.getDefaultFinalizerName())) {
             throw new IllegalStateException("Finalizer is not present.");
         }
 

operator-framework/src/test/java/io/javaoperatorsdk/operator/sample/subresource/SubResourceTestCustomResourceController.java

@@ -19,7 +19,7 @@ public class SubResourceTestCustomResourceController implements ResourceControll
 
     public static final String CRD_NAME = "subresourcesample.sample.javaoperatorsdk";
     private static final Logger log = LoggerFactory.getLogger(SubResourceTestCustomResourceController.class);
-    private AtomicInteger numberOfExecutions = new AtomicInteger(0);
+    private final AtomicInteger numberOfExecutions = new AtomicInteger(0);
 
     @Override
     public boolean deleteResource(SubResourceTestCustomResource resource, Context<SubResourceTestCustomResource> context) {
@@ -30,7 +30,7 @@ public boolean deleteResource(SubResourceTestCustomResource resource, Context<Su
     public UpdateControl<SubResourceTestCustomResource> createOrUpdateResource(SubResourceTestCustomResource resource,
                                                                                Context<SubResourceTestCustomResource> context) {
         numberOfExecutions.addAndGet(1);
-        if (!resource.getMetadata().getFinalizers().contains(Controller.DEFAULT_FINALIZER)) {
+        if (!resource.getMetadata().getFinalizers().contains(this.getDefaultFinalizerName())) {
             throw new IllegalStateException("Finalizer is not present.");
         }
         log.info("Value: " + resource.getSpec().getValue());