feat: make it possible to stream existing configurations

Author: metacosm

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/api/config/AbstractConfigurationService.java

@@ -6,6 +6,7 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.stream.Stream;
 
 public abstract class AbstractConfigurationService implements ConfigurationService {
 
@@ -24,8 +25,8 @@ protected <R extends CustomResource> void replace(ControllerConfiguration<R> con
     put(config, false);
   }
 
-  private <R extends CustomResource> void put(ControllerConfiguration<R> config,
-      boolean failIfExisting) {
+  private <R extends CustomResource> void put(
+      ControllerConfiguration<R> config, boolean failIfExisting) {
     final var name = config.getName();
     if (failIfExisting) {
       final var existing = configurations.get(name);
@@ -61,6 +62,10 @@ protected ControllerConfiguration getFor(String controllerName) {
     return configurations.get(controllerName);
   }
 
+  protected Stream<ControllerConfiguration> controllerConfigurations() {
+    return configurations.values().stream();
+  }
+
   @Override
   public Set<String> getKnownControllerNames() {
     return configurations.keySet();