Fix k8s watcher issue when node access to list nodes and ns (#22714) (#…

…22769)

(cherry picked from commit 1137032)

libbeat/autodiscover/providers/kubernetes/pod.go

@@ -88,13 +88,13 @@ func NewPodEventer(uuid uuid.UUID, cfg *common.Config, client k8s.Interface, pub
 	}
 	nodeWatcher, err := kubernetes.NewWatcher(client, &kubernetes.Node{}, options, nil)
 	if err != nil {
-		return nil, fmt.Errorf("couldn't create watcher for %T due to error %+v", &kubernetes.Node{}, err)
+		logger.Errorf("couldn't create watcher for %T due to error %+v", &kubernetes.Node{}, err)
 	}
 	namespaceWatcher, err := kubernetes.NewWatcher(client, &kubernetes.Namespace{}, kubernetes.WatchOptions{
 		SyncTimeout: config.SyncPeriod,
 	}, nil)
 	if err != nil {
-		return nil, fmt.Errorf("couldn't create watcher for %T due to error %+v", &kubernetes.Namespace{}, err)
+		logger.Errorf("couldn't create watcher for %T due to error %+v", &kubernetes.Namespace{}, err)
 	}
 	metaGen := metadata.GetPodMetaGen(cfg, watcher, nodeWatcher, namespaceWatcher, metaConf)
 

libbeat/common/kubernetes/metadata/metadata.go

@@ -60,8 +60,13 @@ func GetPodMetaGen(
 	namespaceWatcher kubernetes.Watcher,
 	metaConf *AddResourceMetadataConfig) MetaGen {
 
-	nodeMetaGen := NewNodeMetadataGenerator(metaConf.Node, nodeWatcher.Store())
-	namespaceMetaGen := NewNamespaceMetadataGenerator(metaConf.Namespace, namespaceWatcher.Store())
+	var nodeMetaGen, namespaceMetaGen MetaGen
+	if nodeWatcher != nil {
+		nodeMetaGen = NewNodeMetadataGenerator(metaConf.Node, nodeWatcher.Store())
+	}
+	if namespaceWatcher != nil {
+		namespaceMetaGen = NewNamespaceMetadataGenerator(metaConf.Namespace, namespaceWatcher.Store())
+	}
 	metaGen := NewPodMetadataGenerator(cfg, podWatcher.Store(), nodeMetaGen, namespaceMetaGen)
 
 	return metaGen

libbeat/processors/add_kubernetes_metadata/kubernetes.go

@@ -220,13 +220,17 @@ func (k *kubernetesAnnotator) init(config kubeAnnotatorConfig, cfg *common.Confi
 
 		// NOTE: order is important here since pod meta will include node meta and hence node.Store() should
 		// be populated before trying to generate metadata for Pods.
-		if err := nodeWatcher.Start(); err != nil {
-			k.log.Debugf("add_kubernetes_metadata", "Couldn't start node watcher: %v", err)
-			return
+		if nodeWatcher != nil {
+			if err := nodeWatcher.Start(); err != nil {
+				k.log.Debugf("add_kubernetes_metadata", "Couldn't start node watcher: %v", err)
+				return
+			}
 		}
-		if err := namespaceWatcher.Start(); err != nil {
-			k.log.Debugf("add_kubernetes_metadata", "Couldn't start namespace watcher: %v", err)
-			return
+		if namespaceWatcher != nil {
+			if err := namespaceWatcher.Start(); err != nil {
+				k.log.Debugf("add_kubernetes_metadata", "Couldn't start namespace watcher: %v", err)
+				return
+			}
 		}
 		if err := watcher.Start(); err != nil {
 			k.log.Debugf("add_kubernetes_metadata", "Couldn't start pod watcher: %v", err)