feat: automatically derive the the dependent resource type if not specified

Signed-off-by: xstefank <[email protected]>

Author: xstefank

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

@@ -1,5 +1,6 @@
 package io.javaoperatorsdk.operator.processing.dependent;
 
+import java.lang.reflect.ParameterizedType;
 import java.util.Optional;
 
 import io.fabric8.kubernetes.api.model.HasMetadata;
@@ -23,13 +24,22 @@ public abstract class AbstractEventSourceHolderDependentResource<
   private boolean isCacheFillerEventSource;
   protected String eventSourceNameToUse;
 
+  @SuppressWarnings("unchecked")
+  protected AbstractEventSourceHolderDependentResource() {
+    this(null, null);
+  }
+
   protected AbstractEventSourceHolderDependentResource(Class<R> resourceType) {
     this(resourceType, null);
   }
 
   protected AbstractEventSourceHolderDependentResource(Class<R> resourceType, String name) {
     super(name);
-    this.resourceType = resourceType;
+    if (resourceType == null) {
+      this.resourceType = findFirstGenericSuperclass(getClass());
+    } else {
+      this.resourceType = resourceType;
+    }
   }
 
   /**
@@ -116,4 +126,14 @@ protected void onUpdated(P primary, R updated, R actual, Context<P> context) {
   private RecentOperationCacheFiller<R> recentOperationCacheFiller() {
     return (RecentOperationCacheFiller<R>) eventSource;
   }
+
+  @SuppressWarnings("unchecked")
+  private Class<R> findFirstGenericSuperclass(
+      Class<? extends AbstractEventSourceHolderDependentResource> clazz) {
+    while (!(clazz.getGenericSuperclass() instanceof ParameterizedType)) {
+      clazz = (Class<? extends AbstractEventSourceHolderDependentResource>) clazz.getSuperclass();
+    }
+    return (Class<R>)
+        ((ParameterizedType) clazz.getGenericSuperclass()).getActualTypeArguments()[0];
+  }
 }

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

@@ -21,6 +21,8 @@ public abstract class AbstractExternalDependentResource<
 
   private InformerEventSource<?, P> externalStateEventSource;
 
+  protected AbstractExternalDependentResource() {}
+
   @SuppressWarnings("unchecked")
   protected AbstractExternalDependentResource(Class<R> resourceType) {
     super(resourceType);

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/external/AbstractPollingDependentResource.java

@@ -16,6 +16,8 @@ public abstract class AbstractPollingDependentResource<R, P extends HasMetadata>
   public static final Duration DEFAULT_POLLING_PERIOD = Duration.ofMillis(5000);
   private Duration pollingPeriod;
 
+  protected AbstractPollingDependentResource() {}
+
   protected AbstractPollingDependentResource(Class<R> resourceType) {
     this(resourceType, DEFAULT_POLLING_PERIOD);
   }

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/processing/dependent/external/PerResourcePollingDependentResource.java

@@ -14,6 +14,8 @@ public abstract class PerResourcePollingDependentResource<R, P extends HasMetada
     extends AbstractPollingDependentResource<R, P>
     implements PerResourcePollingEventSource.ResourceFetcher<R, P> {
 
+  public PerResourcePollingDependentResource() {}
+
   public PerResourcePollingDependentResource(Class<R> resourceType) {
     super(resourceType);
   }

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

@@ -18,6 +18,8 @@ public abstract class CRUDKubernetesDependentResource<R extends HasMetadata, P e
     extends KubernetesDependentResource<R, P>
     implements Creator<R, P>, Updater<R, P>, GarbageCollected<P> {
 
+  public CRUDKubernetesDependentResource() {}
+
   public CRUDKubernetesDependentResource(Class<R> resourceType) {
     super(resourceType);
   }

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

@@ -41,6 +41,8 @@ public abstract class KubernetesDependentResource<R extends HasMetadata, P exten
   private KubernetesDependentResourceConfig<R> kubernetesDependentResourceConfig;
   private volatile Boolean useSSA;
 
+  public KubernetesDependentResource() {}
+
   public KubernetesDependentResource(Class<R> resourceType) {
     this(resourceType, null);
   }

operator-framework-core/src/test/java/io/javaoperatorsdk/operator/processing/dependent/kubernetes/KubernetesDependentResourceTest.java

@@ -0,0 +1,36 @@
+package io.javaoperatorsdk.operator.processing.dependent.kubernetes;
+
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+import io.fabric8.kubernetes.api.model.apps.Deployment;
+import io.javaoperatorsdk.operator.sample.simple.TestCustomResource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class KubernetesDependentResourceTest {
+
+  @ParameterizedTest
+  @ValueSource(
+      classes = {
+        ParentDeploymentDependentResource.class,
+        ChildTestDeploymentDependentResource.class,
+        GrandChildTestDeploymentDependentResource.class
+      })
+  void checkResourceTypeDerivationWithInheritance(Class<?> clazz) throws Exception {
+    System.out.println(clazz);
+    KubernetesDependentResource<?, ?> dependentResource =
+        (KubernetesDependentResource<?, ?>) clazz.getDeclaredConstructor().newInstance();
+    assertThat(dependentResource).isInstanceOf(KubernetesDependentResource.class);
+    assertThat(dependentResource.resourceType()).isEqualTo(Deployment.class);
+  }
+
+  private static class GrandChildTestDeploymentDependentResource
+      extends ChildTestDeploymentDependentResource {}
+
+  private static class ChildTestDeploymentDependentResource
+      extends ParentDeploymentDependentResource {}
+
+  private static class ParentDeploymentDependentResource
+      extends KubernetesDependentResource<Deployment, TestCustomResource> {}
+}

sample-operators/mysql-schema/src/main/java/io/javaoperatorsdk/operator/sample/dependent/SchemaDependentResource.java

@@ -54,10 +54,6 @@ public class SchemaDependentResource
 
   private MySQLDbConfig dbConfig;
 
-  public SchemaDependentResource() {
-    super(Schema.class);
-  }
-
   @Override
   public Optional<ResourcePollerConfig> configuration() {
     return Optional.of(new ResourcePollerConfig(getPollingPeriod(), dbConfig));

sample-operators/mysql-schema/src/main/java/io/javaoperatorsdk/operator/sample/dependent/SecretDependentResource.java

@@ -27,10 +27,6 @@ public class SecretDependentResource extends KubernetesDependentResource<Secret,
   public static final String MYSQL_SECRET_USERNAME = "mysql.secret.user.name";
   public static final String MYSQL_SECRET_PASSWORD = "mysql.secret.user.password";
 
-  public SecretDependentResource() {
-    super(Secret.class);
-  }
-
   private static String encode(String value) {
     return Base64.getEncoder().encodeToString(value.getBytes());
   }

sample-operators/tomcat-operator/src/main/java/io/javaoperatorsdk/operator/sample/DeploymentDependentResource.java

@@ -14,10 +14,6 @@
 public class DeploymentDependentResource
     extends CRUDKubernetesDependentResource<Deployment, Tomcat> {
 
-  public DeploymentDependentResource() {
-    super(Deployment.class);
-  }
-
   private static String tomcatImage(Tomcat tomcat) {
     return "tomcat:" + tomcat.getSpec().getVersion();
   }