Using Annotations to Identify primary for a secondary object if no owner reference can be added

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/kubernetes/KubernetesDependentResource.java

@@ -1,5 +1,6 @@
 package io.javaoperatorsdk.operator.processing.dependent.kubernetes;
 
+import java.util.HashMap;
 import java.util.Optional;
 import java.util.Set;
 
@@ -11,6 +12,7 @@
 import io.fabric8.kubernetes.client.KubernetesClient;
 import io.fabric8.kubernetes.client.dsl.NonNamespaceOperation;
 import io.fabric8.kubernetes.client.dsl.Resource;
+import io.javaoperatorsdk.operator.OperatorException;
 import io.javaoperatorsdk.operator.api.config.informer.InformerConfiguration;
 import io.javaoperatorsdk.operator.api.reconciler.Context;
 import io.javaoperatorsdk.operator.api.reconciler.EventSourceContext;
@@ -57,18 +59,30 @@ public void configureWith(KubernetesDependentResourceConfig config) {
   @SuppressWarnings("unchecked")
   private void configureWith(String labelSelector, Set<String> namespaces,
       boolean inheritNamespacesOnChange) {
-    final SecondaryToPrimaryMapper<R> primaryResourcesRetriever =
-        (this instanceof SecondaryToPrimaryMapper) ? (SecondaryToPrimaryMapper<R>) this
-            : Mappers.fromOwnerReference();
+
     var ic = InformerConfiguration.from(resourceType())
         .withLabelSelector(labelSelector)
-        .withSecondaryToPrimaryMapper(primaryResourcesRetriever)
+        .withSecondaryToPrimaryMapper(getSecondaryToPrimaryMapper())
         .withNamespaces(namespaces, inheritNamespacesOnChange)
         .build();
 
     configureWith(new InformerEventSource<>(ic, client));
   }
 
+  @SuppressWarnings("unchecked")
+  private SecondaryToPrimaryMapper<R> getSecondaryToPrimaryMapper() {
+    if (this instanceof SecondaryToPrimaryMapper) {
+      return (SecondaryToPrimaryMapper<R>) this;
+    } else if (garbageCollected) {
+      return Mappers.fromOwnerReference();
+    } else if (useDefaultAnnotationsToIdentifyPrimary()) {
+      return Mappers.fromDefaultAnnotations();
+    } else {
+      throw new OperatorException("Provide a SecondaryToPrimaryMapper to associate " +
+          "this resource with the primary resource. DependentResource: " + getClass().getName());
+    }
+  }
+
   /**
    * Use to share informers between event more resources.
    *
@@ -129,6 +143,8 @@ protected NonNamespaceOperation<R, KubernetesResourceList<R>, Resource<R>> prepa
         ResourceID.fromResource(desired));
     if (addOwnerReference()) {
       desired.addOwnerReference(primary);
+    } else if (useDefaultAnnotationsToIdentifyPrimary()) {
+      addDefaultSecondaryToPrimaryMapperAnnotations(desired, primary);
     }
     Class<R> targetClass = (Class<R>) desired.getClass();
     return client.resources(targetClass).inNamespace(desired.getMetadata().getNamespace());
@@ -142,6 +158,24 @@ protected InformerEventSource<R, P> createEventSource(EventSourceContext<P> cont
     return eventSource();
   }
 
+  private boolean useDefaultAnnotationsToIdentifyPrimary() {
+    return !(this instanceof SecondaryToPrimaryMapper) && !garbageCollected && creatable;
+  }
+
+  private void addDefaultSecondaryToPrimaryMapperAnnotations(R desired, P primary) {
+    var annotations = desired.getMetadata().getAnnotations();
+    if (annotations == null) {
+      annotations = new HashMap<>();
+      desired.getMetadata().setAnnotations(annotations);
+    }
+    annotations.put(Mappers.DEFAULT_ANNOTATION_FOR_NAME, primary.getMetadata().getName());
+    var primaryNamespaces = primary.getMetadata().getNamespace();
+    if (primaryNamespaces != null) {
+      annotations.put(
+          Mappers.DEFAULT_ANNOTATION_FOR_NAMESPACE, primary.getMetadata().getNamespace());
+    }
+  }
+
   protected boolean addOwnerReference() {
     return garbageCollected;
   }

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/kubernetes/KubernetesDependentResourceConfig.java

@@ -18,7 +18,7 @@ public KubernetesDependentResourceConfig(Set<String> namespaces, String labelSel
       boolean configuredNS) {
     this.namespaces = namespaces;
     this.labelSelector = labelSelector;
-    namespacesWereConfigured = configuredNS;
+    this.namespacesWereConfigured = configuredNS;
   }
 
   public KubernetesDependentResourceConfig(Set<String> namespaces, String labelSelector) {
@@ -47,4 +47,5 @@ public String labelSelector() {
   public boolean wereNamespacesConfigured() {
     return namespacesWereConfigured;
   }
+
 }

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/event/source/informer/Mappers.java

@@ -9,6 +9,10 @@
 
 public class Mappers {
 
+  public static final String DEFAULT_ANNOTATION_FOR_NAME = "io.javaoperatorsdk/primary-name";
+  public static final String DEFAULT_ANNOTATION_FOR_NAMESPACE =
+      "io.javaoperatorsdk/primary-namespace";
+
   private Mappers() {}
 
   public static <T extends HasMetadata> SecondaryToPrimaryMapper<T> fromAnnotation(
@@ -26,6 +30,10 @@ public static <T extends HasMetadata> SecondaryToPrimaryMapper<T> fromLabel(
     return fromMetadata(nameKey, null, true);
   }
 
+  public static <T extends HasMetadata> SecondaryToPrimaryMapper<T> fromDefaultAnnotations() {
+    return fromMetadata(DEFAULT_ANNOTATION_FOR_NAME, DEFAULT_ANNOTATION_FOR_NAMESPACE, false);
+  }
+
   public static <T extends HasMetadata> SecondaryToPrimaryMapper<T> fromLabel(
       String nameKey, String namespaceKey) {
     return fromMetadata(nameKey, namespaceKey, true);

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

@@ -0,0 +1,66 @@
+package io.javaoperatorsdk.operator;
+
+import java.time.Duration;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
+
+import io.fabric8.kubernetes.api.model.ConfigMap;
+import io.fabric8.kubernetes.api.model.ObjectMetaBuilder;
+import io.javaoperatorsdk.operator.junit.LocalOperatorExtension;
+import io.javaoperatorsdk.operator.sample.dependentannotationsecondarymapper.DependentAnnotationSecondaryMapperReconciler;
+import io.javaoperatorsdk.operator.sample.dependentannotationsecondarymapper.DependentAnnotationSecondaryMapperResource;
+
+import static io.javaoperatorsdk.operator.processing.event.source.informer.Mappers.DEFAULT_ANNOTATION_FOR_NAME;
+import static io.javaoperatorsdk.operator.processing.event.source.informer.Mappers.DEFAULT_ANNOTATION_FOR_NAMESPACE;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.awaitility.Awaitility.await;
+
+class DependentAnnotationSecondaryMapperIT {
+
+  public static final String TEST_RESOURCE_NAME = "test1";
+
+  @RegisterExtension
+  LocalOperatorExtension operator =
+      LocalOperatorExtension.builder()
+          .withReconciler(DependentAnnotationSecondaryMapperReconciler.class)
+          .build();
+
+  @Test
+  void mapsSecondaryByAnnotation() {
+    operator.create(DependentAnnotationSecondaryMapperResource.class, testResource());
+
+    var reconciler =
+        operator.getReconcilerOfType(DependentAnnotationSecondaryMapperReconciler.class);
+
+    await().pollDelay(Duration.ofMillis(150)).untilAsserted(() -> {
+      assertThat(reconciler.getNumberOfExecutions()).isEqualTo(1);
+    });
+    var configMap = operator.get(ConfigMap.class, TEST_RESOURCE_NAME);
+
+    var annotations = configMap.getMetadata().getAnnotations();
+
+    assertThat(annotations)
+        .containsEntry(DEFAULT_ANNOTATION_FOR_NAME, TEST_RESOURCE_NAME)
+        .containsEntry(DEFAULT_ANNOTATION_FOR_NAMESPACE, operator.getNamespace());
+
+    assertThat(configMap.getMetadata().getOwnerReferences()).isEmpty();
+
+    configMap.getData().put("additional_data", "data");
+    operator.replace(ConfigMap.class, configMap);
+
+    await().pollDelay(Duration.ofMillis(150)).untilAsserted(() -> {
+      assertThat(reconciler.getNumberOfExecutions()).isEqualTo(2);
+    });
+  }
+
+
+  DependentAnnotationSecondaryMapperResource testResource() {
+    var res = new DependentAnnotationSecondaryMapperResource();
+    res.setMetadata(new ObjectMetaBuilder()
+        .withName(TEST_RESOURCE_NAME)
+        .build());
+    return res;
+  }
+
+}

operator-framework/src/test/java/io/javaoperatorsdk/operator/sample/dependentannotationsecondarymapper/DependentAnnotationSecondaryMapperReconciler.java

@@ -0,0 +1,58 @@
+package io.javaoperatorsdk.operator.sample.dependentannotationsecondarymapper;
+
+import java.util.Map;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import io.fabric8.kubernetes.api.model.ConfigMap;
+import io.fabric8.kubernetes.api.model.ObjectMetaBuilder;
+import io.javaoperatorsdk.operator.api.reconciler.*;
+import io.javaoperatorsdk.operator.api.reconciler.dependent.Deleter;
+import io.javaoperatorsdk.operator.api.reconciler.dependent.Dependent;
+import io.javaoperatorsdk.operator.processing.dependent.Creator;
+import io.javaoperatorsdk.operator.processing.dependent.Updater;
+import io.javaoperatorsdk.operator.processing.dependent.kubernetes.KubernetesDependentResource;
+import io.javaoperatorsdk.operator.support.TestExecutionInfoProvider;
+
+@ControllerConfiguration(dependents = {@Dependent(
+    type = DependentAnnotationSecondaryMapperReconciler.ConfigMapDependentResource.class)})
+public class DependentAnnotationSecondaryMapperReconciler
+    implements Reconciler<DependentAnnotationSecondaryMapperResource>, TestExecutionInfoProvider {
+
+  private final AtomicInteger numberOfExecutions = new AtomicInteger(0);
+
+  @Override
+  public UpdateControl<DependentAnnotationSecondaryMapperResource> reconcile(
+      DependentAnnotationSecondaryMapperResource resource,
+      Context<DependentAnnotationSecondaryMapperResource> context) {
+    numberOfExecutions.addAndGet(1);
+    return UpdateControl.noUpdate();
+  }
+
+  public int getNumberOfExecutions() {
+    return numberOfExecutions.get();
+  }
+
+  public static class ConfigMapDependentResource extends
+      KubernetesDependentResource<ConfigMap, DependentAnnotationSecondaryMapperResource>
+      implements Creator<ConfigMap, DependentAnnotationSecondaryMapperResource>,
+      Updater<ConfigMap, DependentAnnotationSecondaryMapperResource>,
+      Deleter<DependentAnnotationSecondaryMapperResource> {
+
+    public ConfigMapDependentResource() {
+      super(ConfigMap.class);
+    }
+
+    @Override
+    protected ConfigMap desired(DependentAnnotationSecondaryMapperResource primary,
+        Context<DependentAnnotationSecondaryMapperResource> context) {
+      ConfigMap configMap = new ConfigMap();
+      configMap.setMetadata(new ObjectMetaBuilder()
+          .withName(primary.getMetadata().getName())
+          .withNamespace(primary.getMetadata().getNamespace())
+          .build());
+      configMap.setData(Map.of("data", primary.getMetadata().getName()));
+      return configMap;
+    }
+  }
+
+}

operator-framework/src/test/java/io/javaoperatorsdk/operator/sample/dependentannotationsecondarymapper/DependentAnnotationSecondaryMapperResource.java

@@ -0,0 +1,17 @@
+package io.javaoperatorsdk.operator.sample.dependentannotationsecondarymapper;
+
+import io.fabric8.kubernetes.api.model.Namespaced;
+import io.fabric8.kubernetes.client.CustomResource;
+import io.fabric8.kubernetes.model.annotation.Group;
+import io.fabric8.kubernetes.model.annotation.Kind;
+import io.fabric8.kubernetes.model.annotation.ShortNames;
+import io.fabric8.kubernetes.model.annotation.Version;
+
+@Group("sample.javaoperatorsdk")
+@Version("v1")
+@Kind("MaxIntervalTestCustomResource")
+@ShortNames("mit")
+public class DependentAnnotationSecondaryMapperResource
+    extends CustomResource<Void, DependentAnnotationSecondaryMapperResourceStatus>
+    implements Namespaced {
+}

operator-framework/src/test/java/io/javaoperatorsdk/operator/sample/dependentannotationsecondarymapper/DependentAnnotationSecondaryMapperResourceStatus.java

@@ -0,0 +1,5 @@
+package io.javaoperatorsdk.operator.sample.dependentannotationsecondarymapper;
+
+public class DependentAnnotationSecondaryMapperResourceStatus {
+
+}