feat: add ability to stream secondary resources from Context (#1916)

Author: metacosm

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/api/reconciler/Context.java

@@ -2,6 +2,7 @@
 
 import java.util.Optional;
 import java.util.Set;
+import java.util.stream.Stream;
 
 import io.fabric8.kubernetes.api.model.HasMetadata;
 import io.fabric8.kubernetes.client.KubernetesClient;
@@ -19,6 +20,10 @@ default <R> Optional<R> getSecondaryResource(Class<R> expectedType) {
 
   <R> Set<R> getSecondaryResources(Class<R> expectedType);
 
+  default <R> Stream<R> getSecondaryResourcesAsStream(Class<R> expectedType) {
+    return getSecondaryResources(expectedType).stream();
+  }
+
   @Deprecated(forRemoval = true)
   <R> Optional<R> getSecondaryResource(Class<R> expectedType, String eventSourceName);
 

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/api/reconciler/DefaultContext.java

@@ -3,6 +3,7 @@
 import java.util.Optional;
 import java.util.Set;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 import io.fabric8.kubernetes.api.model.HasMetadata;
 import io.fabric8.kubernetes.client.KubernetesClient;
@@ -35,10 +36,14 @@ public Optional<RetryInfo> getRetryInfo() {
 
   @Override
   public <T> Set<T> getSecondaryResources(Class<T> expectedType) {
+    return getSecondaryResourcesAsStream(expectedType).collect(Collectors.toSet());
+  }
+
+  @Override
+  public <R> Stream<R> getSecondaryResourcesAsStream(Class<R> expectedType) {
     return controller.getEventSourceManager().getResourceEventSourcesFor(expectedType).stream()
         .map(es -> es.getSecondaryResources(primaryResource))
-        .flatMap(Set::stream)
-        .collect(Collectors.toSet());
+        .flatMap(Set::stream);
   }
 
   @Override

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/api/reconciler/ResourceIDMatcherDiscriminator.java

@@ -18,7 +18,7 @@ public ResourceIDMatcherDiscriminator(Function<P, ResourceID> mapper) {
   @Override
   public Optional<R> distinguish(Class<R> resource, P primary, Context<P> context) {
     var resourceID = mapper.apply(primary);
-    return context.getSecondaryResources(resource).stream()
+    return context.getSecondaryResourcesAsStream(resource)
         .filter(resourceID::isSameResource)
         .findFirst();
   }

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

@@ -165,7 +165,7 @@ public <S> ResourceEventSource<S, R> get(Class<S> dependentType, String name) {
 
   @SuppressWarnings("rawtypes")
   private String keyAsString(Class dependentType, String name) {
-    return name != null && name.length() > 0
+    return name != null && !name.isEmpty()
         ? "(" + dependentType.getName() + ", " + name + ")"
         : dependentType.getName();
   }

operator-framework/src/test/java/io/javaoperatorsdk/operator/sample/bulkdependent/ConfigMapDeleterBulkDependentResource.java

@@ -1,6 +1,9 @@
 package io.javaoperatorsdk.operator.sample.bulkdependent;
 
-import java.util.*;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.function.Function;
+import java.util.stream.Collectors;
 
 import io.fabric8.kubernetes.api.model.ConfigMap;
 import io.fabric8.kubernetes.api.model.ObjectMetaBuilder;
@@ -59,15 +62,14 @@ public ConfigMap desired(BulkDependentTestCustomResource primary, String key,
   @Override
   public Map<String, ConfigMap> getSecondaryResources(BulkDependentTestCustomResource primary,
       Context<BulkDependentTestCustomResource> context) {
-    var configMaps = context.getSecondaryResources(ConfigMap.class);
-    Map<String, ConfigMap> result = new HashMap<>(configMaps.size());
-    configMaps.forEach(cm -> {
-      String name = cm.getMetadata().getName();
-      if (name.startsWith(primary.getMetadata().getName())) {
-        String key = name.substring(name.lastIndexOf(INDEX_DELIMITER) + 1);
-        result.put(key, cm);
-      }
-    });
-    return result;
+    return context.getSecondaryResourcesAsStream(ConfigMap.class)
+        .filter(cm -> getName(cm).startsWith(primary.getMetadata().getName()))
+        .collect(Collectors.toMap(
+            cm -> getName(cm).substring(getName(cm).lastIndexOf(INDEX_DELIMITER) + 1),
+            Function.identity()));
+  }
+
+  private static String getName(ConfigMap cm) {
+    return cm.getMetadata().getName();
   }
 }

operator-framework/src/test/java/io/javaoperatorsdk/operator/sample/bulkdependent/external/ExternalBulkDependentResource.java

@@ -1,6 +1,9 @@
 package io.javaoperatorsdk.operator.sample.bulkdependent.external;
 
-import java.util.*;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
 import java.util.stream.Collectors;
 
 import io.javaoperatorsdk.operator.api.reconciler.Context;
@@ -75,7 +78,7 @@ public Map<String, ExternalResource> desiredResources(BulkDependentTestCustomRes
   public Map<String, ExternalResource> getSecondaryResources(
       BulkDependentTestCustomResource primary,
       Context<BulkDependentTestCustomResource> context) {
-    return context.getSecondaryResources(resourceType()).stream()
+    return context.getSecondaryResourcesAsStream(resourceType())
         .filter(r -> r.getId()
             .startsWith(primary.getMetadata().getName() + EXTERNAL_RESOURCE_NAME_DELIMITER +
                 primary.getMetadata().getNamespace() +