improve: api for dynamic registration of event sources (#2162)

fixes also a typo

Signed-off-by: Attila Mészáros <csviri@gmail.com>

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

@@ -84,7 +84,7 @@ private <R> void registerOrDeregisterEventSourceBasedOnActivation(boolean activa
       if (activationConditionMet) {
         var eventSource =
             dependentResourceNode.getDependentResource().eventSource(context.eventSourceRetriever()
-                .eventSourceContexForDynamicRegistration());
+                .eventSourceContextForDynamicRegistration());
         var es = eventSource.orElseThrow();
         context.eventSourceRetriever()
             .dynamicallyRegisterEventSource(dependentResourceNode.getName(), es);

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

@@ -1,10 +1,6 @@
 package io.javaoperatorsdk.operator.processing.event;
 
-import java.util.LinkedHashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Objects;
-import java.util.Set;
+import java.util.*;
 import java.util.function.Function;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
@@ -233,24 +229,28 @@ public <R> List<ResourceEventSource<R, P>> getResourceEventSourcesFor(Class<R> d
   }
 
   @Override
-  public synchronized void dynamicallyRegisterEventSource(String name, EventSource eventSource) {
-    if (eventSources.existing(name, eventSource) != null) {
-      return;
+  public synchronized EventSource dynamicallyRegisterEventSource(String name,
+      EventSource eventSource) {
+    var es = eventSources.existing(name, eventSource);
+    if (es != null) {
+      return es;
     }
     registerEventSource(name, eventSource);
     eventSource.start();
+    return eventSource;
   }
 
   @Override
-  public synchronized void dynamicallyDeRegisterEventSource(String name) {
+  public synchronized Optional<EventSource> dynamicallyDeRegisterEventSource(String name) {
     EventSource es = eventSources.remove(name);
     if (es != null) {
       es.stop();
     }
+    return Optional.ofNullable(es);
   }
 
   @Override
-  public EventSourceContext<P> eventSourceContexForDynamicRegistration() {
+  public EventSourceContext<P> eventSourceContextForDynamicRegistration() {
     return controller.eventSourceContext();
   }
 

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

@@ -1,6 +1,7 @@
 package io.javaoperatorsdk.operator.processing.event;
 
 import java.util.List;
+import java.util.Optional;
 
 import io.fabric8.kubernetes.api.model.HasMetadata;
 import io.javaoperatorsdk.operator.api.reconciler.EventSourceContext;
@@ -40,8 +41,9 @@ default <R> ResourceEventSource<R, P> getResourceEventSourceFor(Class<R> depende
    *
    * @param name of the event source
    * @param eventSource to register
+   * @return the actual event source registered. Might not be the same as the parameter.
    */
-  void dynamicallyRegisterEventSource(String name, EventSource eventSource);
+  EventSource dynamicallyRegisterEventSource(String name, EventSource eventSource);
 
   /**
    * De-registers (and stops) the {@link EventSource} associated with the specified name. If no such
@@ -57,9 +59,10 @@ default <R> ResourceEventSource<R, P> getResourceEventSourceFor(Class<R> depende
    * </p>
    *
    * @param name of the event source
+   * @return the actual event source deregistered if there is one.
    */
-  void dynamicallyDeRegisterEventSource(String name);
+  Optional<EventSource> dynamicallyDeRegisterEventSource(String name);
 
-  EventSourceContext<P> eventSourceContexForDynamicRegistration();
+  EventSourceContext<P> eventSourceContextForDynamicRegistration();
 
 }