feat: add getPlural method on GroupVersionKind

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/GroupVersionKind.java

@@ -1,13 +1,18 @@
 package io.javaoperatorsdk.operator.processing;
 
+import java.util.Map;
 import java.util.Objects;
+import java.util.concurrent.ConcurrentHashMap;
 
 import io.fabric8.kubernetes.api.model.HasMetadata;
 
 public class GroupVersionKind {
   private final String group;
   private final String version;
   private final String kind;
+  private final String apiVersion;
+  protected final static Map<Class<? extends HasMetadata>, GroupVersionKind> CACHE =
+      new ConcurrentHashMap<>();
 
   public GroupVersionKind(String apiVersion, String kind) {
     this.kind = kind;
@@ -19,17 +24,23 @@ public GroupVersionKind(String apiVersion, String kind) {
       this.group = groupAndVersion[0];
       this.version = groupAndVersion[1];
     }
+    this.apiVersion = apiVersion;
+  }
+
+  public static GroupVersionKind gvkFor(Class<? extends HasMetadata> resourceClass) {
+    return CACHE.computeIfAbsent(resourceClass, GroupVersionKind::computeGVK);
+  }
+
+  private static GroupVersionKind computeGVK(Class<? extends HasMetadata> rc) {
+    return new GroupVersionKind(HasMetadata.getGroup(rc),
+        HasMetadata.getVersion(rc), HasMetadata.getKind(rc));
   }
 
   public GroupVersionKind(String group, String version, String kind) {
     this.group = group;
     this.version = version;
     this.kind = kind;
-  }
-
-  public static GroupVersionKind gvkFor(Class<? extends HasMetadata> resourceClass) {
-    return new GroupVersionKind(HasMetadata.getGroup(resourceClass),
-        HasMetadata.getVersion(resourceClass), HasMetadata.getKind(resourceClass));
+    this.apiVersion = (group == null || group.isBlank()) ? version : group + "/" + version;
   }
 
   public String getGroup() {
@@ -45,7 +56,7 @@ public String getKind() {
   }
 
   public String apiVersion() {
-    return group == null || group.isBlank() ? version : group + "/" + version;
+    return apiVersion;
   }
 
   @Override
@@ -55,20 +66,18 @@ public boolean equals(Object o) {
     if (o == null || getClass() != o.getClass())
       return false;
     GroupVersionKind that = (GroupVersionKind) o;
-    return Objects.equals(group, that.group) && Objects.equals(version, that.version)
-        && Objects.equals(kind, that.kind);
+    return Objects.equals(apiVersion, that.apiVersion) && Objects.equals(kind, that.kind);
   }
 
   @Override
   public int hashCode() {
-    return Objects.hash(group, version, kind);
+    return Objects.hash(apiVersion, kind);
   }
 
   @Override
   public String toString() {
     return "GroupVersionKind{" +
-        "group='" + group + '\'' +
-        ", version='" + version + '\'' +
+        "apiVersion='" + apiVersion + '\'' +
         ", kind='" + kind + '\'' +
         '}';
   }

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

@@ -8,9 +8,13 @@
 public class GenericKubernetesDependentResource<P extends HasMetadata>
     extends KubernetesDependentResource<GenericKubernetesResource, P> {
 
-  private final GroupVersionKind groupVersionKind;
+  private final GroupVersionKindPlural groupVersionKind;
 
   public GenericKubernetesDependentResource(GroupVersionKind groupVersionKind) {
+    this(GroupVersionKindPlural.from(groupVersionKind));
+  }
+
+  public GenericKubernetesDependentResource(GroupVersionKindPlural groupVersionKind) {
     super(GenericKubernetesResource.class);
     this.groupVersionKind = groupVersionKind;
   }
@@ -20,7 +24,7 @@ protected InformerConfiguration.InformerConfigurationBuilder<GenericKubernetesRe
   }
 
   @SuppressWarnings("unused")
-  public GroupVersionKind getGroupVersionKind() {
+  public GroupVersionKindPlural getGroupVersionKind() {
     return groupVersionKind;
   }
 }

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

@@ -0,0 +1,111 @@
+package io.javaoperatorsdk.operator.processing.dependent.kubernetes;
+
+import java.util.Optional;
+
+import io.fabric8.kubernetes.api.Pluralize;
+import io.fabric8.kubernetes.api.model.HasMetadata;
+import io.javaoperatorsdk.operator.processing.GroupVersionKind;
+
+/**
+ * An extension of {@link GroupVersionKind} that also records the associated plural form which is
+ * useful when dealing with Kubernetes RBACs. Downstream projects might leverage that information.
+ */
+public class GroupVersionKindPlural extends GroupVersionKind {
+  private final String plural;
+
+  protected GroupVersionKindPlural(String group, String version, String kind, String plural) {
+    super(group, version, kind);
+    this.plural = plural;
+  }
+
+  protected GroupVersionKindPlural(String apiVersion, String kind, String plural) {
+    super(apiVersion, kind);
+    this.plural = plural;
+  }
+
+  protected GroupVersionKindPlural(GroupVersionKind gvk, String plural) {
+    this(gvk.getGroup(), gvk.getVersion(), gvk.getKind(),
+        plural != null ? plural
+            : (gvk instanceof GroupVersionKindPlural ? ((GroupVersionKindPlural) gvk).plural
+                : null));
+  }
+
+  /**
+   * Creates a new GroupVersionKindPlural from the specified {@link GroupVersionKind}.
+   *
+   * @param gvk a {@link GroupVersionKind} from which to create a new GroupVersionKindPlural object
+   * @return a new GroupVersionKindPlural object matching the specified {@link GroupVersionKind}
+   */
+  public static GroupVersionKindPlural from(GroupVersionKind gvk) {
+    return gvk instanceof GroupVersionKindPlural ? ((GroupVersionKindPlural) gvk)
+        : gvkWithPlural(gvk, null);
+  }
+
+  /**
+   * Creates a new GroupVersionKindPlural based on the specified {@link GroupVersionKind} instance
+   * but specifying a plural form to use as well.
+   *
+   * @param gvk the base {@link GroupVersionKind} from which to derive a new GroupVersionKindPlural
+   * @param plural the plural form to use for the new instance or {@code null} if the default plural
+   *        form is desired. Note that the specified plural form will override any existing plural
+   *        form for the specified {@link GroupVersionKind} (in particular, if the specified
+   *        {@link GroupVersionKind} was already an instance of GroupVersionKindPlural, its plural
+   *        form will only be considered in the new instance if the specified plural form is
+   *        {@code null}
+   * @return a new GroupVersionKindPlural derived from the specified {@link GroupVersionKind} and
+   *         plural form
+   */
+  public static GroupVersionKindPlural gvkWithPlural(GroupVersionKind gvk, String plural) {
+    return new GroupVersionKindPlural(gvk, plural);
+  }
+
+  /**
+   * Creates a new GroupVersionKindPlural instance extracting the information from the specified
+   * {@link HasMetadata} implementation
+   *
+   * @param resourceClass the {@link HasMetadata} from which group, version, kind and plural form
+   *        are extracted
+   * @return a new GroupVersionKindPlural instance based on the specified {@link HasMetadata}
+   *         implementation
+   */
+  public static GroupVersionKindPlural gvkFor(Class<? extends HasMetadata> resourceClass) {
+    final var gvk = GroupVersionKind.gvkFor(resourceClass);
+    return gvkWithPlural(gvk, HasMetadata.getPlural(resourceClass));
+  }
+
+  /**
+   * Retrieves the default plural form for the specified kind.
+   *
+   * @param kind the kind for which we want to get the default plural form
+   * @return the default plural form for the specified kind
+   */
+  public static String getDefaultPluralFor(String kind) {
+    // todo: replace by Fabric8 version when available, see
+    // https://github.com/fabric8io/kubernetes-client/pull/6314
+    return kind != null ? Pluralize.toPlural(kind.toLowerCase()) : null;
+  }
+
+  /**
+   * Returns the plural form associated with the kind if it has been provided explicitly (either
+   * manually by the user, or determined from the associated resource class definition)
+   *
+   * @return {@link Optional#empty()} if the plural form was not provided explicitly, or the plural
+   *         form if it was provided explicitly
+   */
+  public Optional<String> getPlural() {
+    return Optional.ofNullable(plural);
+  }
+
+  /**
+   * Returns the plural form associated with the kind if it was provided or a default, computed form
+   * via {@link #getDefaultPluralFor(String)} (which should correspond to the actual plural form in
+   * most cases but might not always be correct, especially if the resource's creator defined an
+   * exotic plural form via the CRD.
+   *
+   * @return the plural form associated with the kind if provided or a default plural form otherwise
+   */
+  @SuppressWarnings("unused")
+  public String getPluralOrDefault() {
+    return getPlural().orElse(getDefaultPluralFor(getKind()));
+  }
+}

operator-framework-core/src/test/java/io/javaoperatorsdk/operator/processing/GroupVersionKindTest.java

@@ -2,8 +2,11 @@
 
 import org.junit.jupiter.api.Test;
 
+import io.fabric8.kubernetes.api.model.ConfigMap;
+import io.fabric8.kubernetes.api.model.HasMetadata;
+import io.javaoperatorsdk.operator.processing.dependent.kubernetes.GroupVersionKindPlural;
+
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.jupiter.api.Assertions.*;
 
 class GroupVersionKindTest {
 
@@ -18,4 +21,39 @@ void testInitFromApiVersion() {
     assertThat(gvk.getVersion()).isEqualTo("v1");
   }
 
+  @Test
+  void pluralShouldOnlyBeProvidedIfExplicitlySet() {
+    final var kind = "ConfigMap";
+    var gvk = GroupVersionKindPlural.from(new GroupVersionKind("v1", kind));
+    assertThat(gvk.getPlural()).isEmpty();
+    assertThat(gvk.getPluralOrDefault())
+        .isEqualTo(GroupVersionKindPlural.getDefaultPluralFor(kind));
+
+    gvk = GroupVersionKindPlural.from(GroupVersionKind.gvkFor(ConfigMap.class));
+    assertThat(gvk.getPlural()).isEmpty();
+    assertThat(gvk.getPluralOrDefault()).isEqualTo(HasMetadata.getPlural(ConfigMap.class));
+
+    gvk = GroupVersionKindPlural.gvkFor(ConfigMap.class);
+    assertThat(gvk.getPlural()).hasValue(HasMetadata.getPlural(ConfigMap.class));
+
+    gvk = GroupVersionKindPlural.from(gvk);
+    assertThat(gvk.getPlural()).hasValue(HasMetadata.getPlural(ConfigMap.class));
+  }
+
+  @Test
+  void pluralShouldBeEmptyIfNotProvided() {
+    final var kind = "MyKind";
+    var gvk =
+        GroupVersionKindPlural.gvkWithPlural(new GroupVersionKind("josdk.io", "v1", kind), null);
+    assertThat(gvk.getPlural()).isEmpty();
+    assertThat(gvk.getPluralOrDefault())
+        .isEqualTo(GroupVersionKindPlural.getDefaultPluralFor(kind));
+  }
+
+  @Test
+  void pluralShouldOverrideDefaultComputedVersionIfProvided() {
+    var gvk = GroupVersionKindPlural.gvkWithPlural(new GroupVersionKind("josdk.io", "v1", "MyKind"),
+        "MyPlural");
+    assertThat(gvk.getPlural()).hasValue("MyPlural");
+  }
 }

operator-framework/src/test/java/io/javaoperatorsdk/operator/sample/dynamicgenericeventsourceregistration/DynamicGenericEventSourceRegistrationReconciler.java

@@ -66,16 +66,12 @@ private ConfigMap configMap(DynamicGenericEventSourceRegistrationCustomResource
     return cm;
   }
 
-  private GroupVersionKind gvkFor(Class<? extends HasMetadata> clazz) {
-    return new GroupVersionKind(HasMetadata.getApiVersion(clazz), HasMetadata.getKind(clazz));
-  }
-
   private InformerEventSource<GenericKubernetesResource, DynamicGenericEventSourceRegistrationCustomResource> genericInformerFor(
       Class<? extends HasMetadata> clazz,
       Context<DynamicGenericEventSourceRegistrationCustomResource> context) {
 
     return new InformerEventSource<>(
-        InformerConfiguration.from(gvkFor(clazz),
+        InformerConfiguration.from(GroupVersionKind.gvkFor(clazz),
             context.eventSourceRetriever().eventSourceContextForDynamicRegistration()).build(),
         context.eventSourceRetriever().eventSourceContextForDynamicRegistration());
   }