addressing review comments

prog/kube-utils/main.go

@@ -72,7 +72,8 @@ type weaveClient interface {
 
 // For each of those peers that is no longer listed as a node by
 // Kubernetes, remove it from Weave IPAM
-func reclaimRemovedPeers(kube kubernetes.Interface, weave weaveClient, cml *configMapAnnotations, myPeerName, myNodeName string) error {
+func reclaimRemovedPeers(kube kubernetes.Interface, cml *configMapAnnotations, myPeerName, myNodeName string) error {
+	weave := weaveapi.NewClient(os.Getenv("WEAVE_HTTP_ADDR"), common.Log)
 	for loopsWhenNothingChanged := 0; loopsWhenNothingChanged < 3; loopsWhenNothingChanged++ {
 		if err := cml.Init(); err != nil {
 			return err
@@ -209,8 +210,18 @@ func registerForNodeUpdates(client *kubernetes.Clientset, stopCh <-chan struct{}
 	common.Log.Debugln("registering for updates for node delete events")
 	nodeInformer.AddEventHandler(cache.ResourceEventHandlerFuncs{
 		DeleteFunc: func(obj interface{}) {
-			node := obj.(*v1core.Node)
-			common.Log.Debugln("[kube-peers] Nodes deleted:", node.Name)
+			nodeObj, ok := obj.(*v1core.Node)
+			if !ok {
+				tombstone, ok := obj.(cache.DeletedFinalStateUnknown)
+				if !ok {
+					common.Log.Fatalf("[kube-peers] Couldn't get node object from tombstone: %#v", obj)
+				}
+				nodeObj, ok = tombstone.Obj.(*v1core.Node)
+				if !ok {
+					common.Log.Fatalf("[kube-peers] Tombstone contained object that is not a Node: %#v", obj)
+				}
+			}
+			common.Log.Debugln("[kube-peers] Nodes deleted:", nodeObj.Name)
 			config, err := rest.InClusterConfig()
 			if err != nil {
 				common.Log.Fatalf("[kube-peers] Could not get cluster config: %v", err)
@@ -220,14 +231,13 @@ func registerForNodeUpdates(client *kubernetes.Clientset, stopCh <-chan struct{}
 				common.Log.Fatalf("[kube-peers] Could not make Kubernetes connection: %v", err)
 			}
 			cml := newConfigMapAnnotations(configMapNamespace, configMapName, client)
-			weave := weaveapi.NewClient(os.Getenv("WEAVE_HTTP_ADDR"), common.Log)
 
 			// add random delay to avoid all nodes acting on node delete event at the same
 			// time leading to contention to use `weave-net` configmap
 			r := rand.Intn(5000)
 			time.Sleep(time.Duration(r) * time.Millisecond)
 
-			err = reclaimRemovedPeers(client, weave, cml, peerName, nodeName)
+			err = reclaimRemovedPeers(client, cml, peerName, nodeName)
 			if err != nil {
 				common.Log.Fatalf("[kube-peers] Error while reclaiming space: %v", err)
 			}
@@ -296,8 +306,7 @@ func main() {
 		}
 		common.Log.Infoln("[kube-peers] Added myself to peer list", list)
 
-		weave := weaveapi.NewClient(os.Getenv("WEAVE_HTTP_ADDR"), common.Log)
-		err = reclaimRemovedPeers(c, weave, cml, peerName, nodeName)
+		err = reclaimRemovedPeers(c, cml, peerName, nodeName)
 		if err != nil {
 			common.Log.Fatalf("[kube-peers] Error while reclaiming space: %v", err)
 		}