fix(kubernetes): teach deployManifest stages to handle label selectors with generateName (#6265)

This fixes:

java.lang.NullPointerException: Cannot invoke "com.netflix.spinnaker.clouddriver.kubernetes.description.manifest.KubernetesManifest.getNamespace()" because "manifest" is null
	at com.netflix.spinnaker.clouddriver.kubernetes.op.OperationResult.addManifest(OperationResult.java:46)
	at com.netflix.spinnaker.clouddriver.kubernetes.op.handler.CanDeploy.deploy(CanDeploy.java:44)
	at com.netflix.spinnaker.clouddriver.kubernetes.op.manifest.KubernetesDeployManifestOperation.lambda$operate$3(KubernetesDeployManifestOperation.java:174)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
	at com.netflix.spinnaker.clouddriver.kubernetes.op.manifest.KubernetesDeployManifestOperation.operate(KubernetesDeployManifestOperation.java:162)
	at com.netflix.spinnaker.clouddriver.kubernetes.op.manifest.KubernetesDeployManifestOperation.operate(KubernetesDeployManifestOperation.java:48)
	at com.netflix.spinnaker.clouddriver.orchestration.AtomicOperation$operate.call(Unknown Source)
	at com.netflix.spinnaker.clouddriver.orchestration.DefaultOrchestrationProcessor$_process_closure1$_closure2.doCall(DefaultOrchestrationProcessor.groovy:120)
	at com.netflix.spinnaker.clouddriver.orchestration.DefaultOrchestrationProcessor$_process_closure1$_closure2.doCall(DefaultOrchestrationProcessor.groovy)
	at jdk.internal.reflect.GeneratedMethodAccessor373.invoke(Unknown Source)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
	at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:107)
	at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:323)
	at org.codehaus.groovy.runtime.metaclass.ClosureMetaClass.invokeMethod(ClosureMetaClass.java:274)
	at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1035)
	at groovy.lang.Closure.call(Closure.java:412)
	at groovy.lang.Closure.call(Closure.java:406)
	at com.netflix.spinnaker.clouddriver.metrics.TimedCallable$CallableWrapper.call(TimedCallable.java:81)
	at com.netflix.spinnaker.clouddriver.metrics.TimedCallable.call(TimedCallable.java:45)
	at java_util_concurrent_Callable$call.call(Unknown Source)
	at com.netflix.spinnaker.clouddriver.orchestration.DefaultOrchestrationProcessor$_process_closure1.doCall(DefaultOrchestrationProcessor.groovy:119)
	at com.netflix.spinnaker.clouddriver.orchestration.DefaultOrchestrationProcessor$_process_closure1.doCall(DefaultOrchestrationProcessor.groovy)
	at jdk.internal.reflect.GeneratedMethodAccessor367.invoke(Unknown Source)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
	at org.codehaus.groovy.reflection.CachedMethod.invoke(CachedMethod.java:107)
	at groovy.lang.MetaMethod.doMethodInvoke(MetaMethod.java:323)
	at org.codehaus.groovy.runtime.metaclass.ClosureMetaClass.invokeMethod(ClosureMetaClass.java:274)
	at groovy.lang.MetaClassImpl.invokeMethod(MetaClassImpl.java:1035)
	at groovy.lang.Closure.call(Closure.java:412)
	at groovy.lang.Closure.call(Closure.java:406)
	at com.netflix.spinnaker.security.AuthenticatedRequest.lambda$wrapCallableForPrincipal$0(AuthenticatedRequest.java:272)
	at com.netflix.spinnaker.clouddriver.metrics.TimedCallable.call(TimedCallable.java:45)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
	at java.base/java.lang.Thread.run(Thread.java:840)

Author: dbyron-sf

clouddriver-kubernetes/src/main/java/com/netflix/spinnaker/clouddriver/kubernetes/op/handler/CanDeploy.java

@@ -41,7 +41,11 @@ default OperationResult deploy(
     // require looking up a manifest by name, which will fail.
     if (manifest.hasGenerateName()) {
       KubernetesManifest result = credentials.create(manifest, task, opName, labelSelectors);
-      return new OperationResult().addManifest(result);
+      OperationResult operationResult = new OperationResult();
+      if (result != null) {
+        operationResult.addManifest(result);
+      }
+      return operationResult;
     }
 
     KubernetesManifest deployedManifest;

clouddriver-kubernetes/src/test/java/com/netflix/spinnaker/clouddriver/kubernetes/op/handler/CanDeployTest.java

@@ -267,4 +267,30 @@ void nullManifest() {
     verify(credentials).deploy(manifest, task, OP_NAME, selectorList);
     assertThat(result.getManifests()).isEmpty();
   }
+
+  @Test
+  void nullManifestWithGenerateName() {
+    KubernetesCredentials credentials = mock(KubernetesCredentials.class);
+    KubernetesManifest manifest =
+        ManifestFetcher.getManifest("candeploy/deployment-generate-name.yml");
+    assertThat(manifest.getGenerateName()).isNotBlank();
+
+    KubernetesSelectorList selectorList = new KubernetesSelectorList();
+    when(credentials.create(manifest, task, OP_NAME, selectorList)).thenReturn(null);
+
+    // DeployStrategy.APPLY and ServerSideApplyStrategy.DEFAULT are arbitrary
+    // too since they're ignored for manifests with generateName.
+    OperationResult result =
+        handler.deploy(
+            credentials,
+            manifest,
+            DeployStrategy.APPLY,
+            ServerSideApplyStrategy.DEFAULT,
+            task,
+            OP_NAME,
+            selectorList);
+
+    verify(credentials).create(manifest, task, OP_NAME, selectorList);
+    assertThat(result.getManifests()).isEmpty();
+  }
 }