Split out HealthCheckNodePort stuff from service/endpoint map Update()

In addition to actually updating their data from the provided list of
changes, EndpointsMap.Update() and ServicePortMap.Update() return a
struct with some information about things that changed because of that
update (eg services with stale conntrack entries).

For some reason, they were also returning information about
HealthCheckNodePorts, but they were returning *static* information
based on the current (post-Update) state of the map, not information
about what had *changed* in the update. Since this doesn't match how
the other data in the struct is used (and since there's no reason to
have the data only be returned when you call Update() anyway) , split
it out.

pkg/proxy/endpoints.go

@@ -293,8 +293,6 @@ type endpointsChange struct {
 
 // UpdateEndpointMapResult is the updated results after applying endpoints changes.
 type UpdateEndpointMapResult struct {
-	// HCEndpointsLocalIPSize maps an endpoints name to the length of its local IPs.
-	HCEndpointsLocalIPSize map[types.NamespacedName]int
 	// StaleEndpoints identifies if an endpoints service pair is stale.
 	StaleEndpoints []ServiceEndpoint
 	// StaleServiceNames identifies if a service is stale.
@@ -313,15 +311,6 @@ func (em EndpointsMap) Update(changes *EndpointChangeTracker) (result UpdateEndp
 
 	em.apply(
 		changes, &result.StaleEndpoints, &result.StaleServiceNames, &result.LastChangeTriggerTimes)
-
-	// TODO: If this will appear to be computationally expensive, consider
-	// computing this incrementally similarly to endpointsMap.
-	result.HCEndpointsLocalIPSize = make(map[types.NamespacedName]int)
-	localIPs := em.getLocalReadyEndpointIPs()
-	for nsn, ips := range localIPs {
-		result.HCEndpointsLocalIPSize[nsn] = len(ips)
-	}
-
 	return result
 }
 
@@ -366,7 +355,7 @@ func (em EndpointsMap) unmerge(other EndpointsMap) {
 	}
 }
 
-// GetLocalEndpointIPs returns endpoints IPs if given endpoint is local - local means the endpoint is running in same host as kube-proxy.
+// getLocalEndpointIPs returns endpoints IPs if given endpoint is local - local means the endpoint is running in same host as kube-proxy.
 func (em EndpointsMap) getLocalReadyEndpointIPs() map[types.NamespacedName]sets.String {
 	localIPs := make(map[types.NamespacedName]sets.String)
 	for svcPortName, epList := range em {
@@ -389,6 +378,25 @@ func (em EndpointsMap) getLocalReadyEndpointIPs() map[types.NamespacedName]sets.
 	return localIPs
 }
 
+// LocalReadyEndpoints returns a map of Service names to the number of local ready
+// endpoints for that service.
+func (em EndpointsMap) LocalReadyEndpoints() map[types.NamespacedName]int {
+	// TODO: If this will appear to be computationally expensive, consider
+	// computing this incrementally similarly to endpointsMap.
+
+	// (Note that we need to call getLocalEndpointIPs first to squash the data by IP,
+	// because the EndpointsMap is sorted by IP+port, not just IP, and we want to
+	// consider a Service pointing to 10.0.0.1:80 and 10.0.0.1:443 to have 1 endpoint,
+	// not 2.)
+
+	eps := make(map[types.NamespacedName]int)
+	localIPs := em.getLocalReadyEndpointIPs()
+	for nsn, ips := range localIPs {
+		eps[nsn] = len(ips)
+	}
+	return eps
+}
+
 // detectStaleConnections modifies <staleEndpoints> and <staleServices> with detected stale connections. <staleServiceNames>
 // is used to store stale udp service in order to clear udp conntrack later.
 func detectStaleConnections(oldEndpointsMap, newEndpointsMap EndpointsMap, staleEndpoints *[]ServiceEndpoint, staleServiceNames *[]ServicePortName) {