fix(NPC): check if new pod is actionable

Previously, kube-router would do a full sync on a new pod whether or not
the pod was in an actionable state. This led to needless syncs as many
pods were missing PodIP addresses or other items necessary to apply
policy.

If a pod is missing these items it is better to wait for the next
message that comes via the UpdateFunc below so that we know that the pod
has all of the necessary items to apply policy to it.

Author: aauren

pkg/controllers/netpol/pod.go

@@ -14,8 +14,13 @@ import (
 func (npc *NetworkPolicyController) newPodEventHandler() cache.ResourceEventHandler {
 	return cache.ResourceEventHandlerFuncs{
 		AddFunc: func(obj interface{}) {
-			npc.OnPodUpdate(obj)
-
+			if podObj, ok := obj.(*api.Pod); ok {
+				// If the pod isn't yet actionable there is no action to take here anyway, so skip it. When it becomes
+				// actionable, we'll get an update below.
+				if isNetPolActionable(podObj) {
+					npc.OnPodUpdate(obj)
+				}
+			}
 		},
 		UpdateFunc: func(oldObj, newObj interface{}) {
 			newPodObj := newObj.(*api.Pod)