Remove usage of TopologyAwareHints feature-gate from kube-proxy packages.

TopologyAwareHints feature-gate is GA'd and enabled by default since 1.33. Since
it is also locked-to-default, we can remove flag-usages in kube-proxy.

NOTE that as per
https://github.com/kubernetes/community/blob/master/contributors/devel/sig-architecture/feature-gates.md#disablement-tests:
_"Disablement tests are only required to be preserved for components and
libraries that support compatibility version. Tests for node and kubelet are
unaffected by compatibility version."_

pkg/proxy/endpointslicecache.go

@@ -25,9 +25,7 @@ import (
 	discovery "k8s.io/api/discovery/v1"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/apimachinery/pkg/util/sets"
-	utilfeature "k8s.io/apiserver/pkg/util/feature"
 	"k8s.io/klog/v2"
-	"k8s.io/kubernetes/pkg/features"
 	utilnet "k8s.io/utils/net"
 )
 
@@ -213,12 +211,10 @@ func (cache *EndpointSliceCache) addEndpoints(svcPortName *ServicePortName, port
 		terminating := endpoint.Conditions.Terminating != nil && *endpoint.Conditions.Terminating
 
 		var zoneHints sets.Set[string]
-		if utilfeature.DefaultFeatureGate.Enabled(features.TopologyAwareHints) {
+		if endpoint.Hints != nil && len(endpoint.Hints.ForZones) > 0 {
-			if endpoint.Hints != nil && len(endpoint.Hints.ForZones) > 0 {
+			zoneHints = sets.New[string]()
-				zoneHints = sets.New[string]()
+			for _, zone := range endpoint.Hints.ForZones {
-				for _, zone := range endpoint.Hints.ForZones {
+				zoneHints.Insert(zone.Name)
-					zoneHints.Insert(zone.Name)
-				}
 			}
 		}
 

pkg/proxy/serviceport.go

@@ -56,8 +56,6 @@ type ServicePort interface {
 	ExternalPolicyLocal() bool
 	// InternalPolicyLocal returns if a service has only node local endpoints for internal traffic.
 	InternalPolicyLocal() bool
-	// HintsAnnotation returns the value of the v1.DeprecatedAnnotationTopologyAwareHints annotation.
-	HintsAnnotation() string
 	// ExternallyAccessible returns true if the service port is reachable via something
 	// other than ClusterIP (NodePort/ExternalIP/LoadBalancer)
 	ExternallyAccessible() bool
@@ -86,7 +84,6 @@ type BaseServicePortInfo struct {
 	healthCheckNodePort      int
 	externalPolicyLocal      bool
 	internalPolicyLocal      bool
-	hintsAnnotation          string
 }
 
 var _ ServicePort = &BaseServicePortInfo{}
@@ -156,11 +153,6 @@ func (bsvcPortInfo *BaseServicePortInfo) InternalPolicyLocal() bool {
 	return bsvcPortInfo.internalPolicyLocal
 }
 
-// HintsAnnotation is part of ServicePort interface.
-func (bsvcPortInfo *BaseServicePortInfo) HintsAnnotation() string {
-	return bsvcPortInfo.hintsAnnotation
-}
-
 // ExternallyAccessible is part of ServicePort interface.
 func (bsvcPortInfo *BaseServicePortInfo) ExternallyAccessible() bool {
 	return bsvcPortInfo.nodePort != 0 || len(bsvcPortInfo.loadBalancerVIPs) != 0 || len(bsvcPortInfo.externalIPs) != 0
@@ -201,13 +193,6 @@ func newBaseServiceInfo(service *v1.Service, ipFamily v1.IPFamily, port *v1.Serv
 		internalPolicyLocal: internalPolicyLocal,
 	}
 
-	// v1.DeprecatedAnnotationTopologyAwareHints has precedence over v1.AnnotationTopologyMode.
-	var exists bool
-	info.hintsAnnotation, exists = service.Annotations[v1.DeprecatedAnnotationTopologyAwareHints]
-	if !exists {
-		info.hintsAnnotation = service.Annotations[v1.AnnotationTopologyMode]
-	}
-
 	// Filter ExternalIPs to correct IP family
 	ipFamilyMap := proxyutil.MapIPsByIPFamily(service.Spec.ExternalIPs)
 	info.externalIPs = ipFamilyMap[ipFamily]

pkg/proxy/topology.go

@@ -135,7 +135,7 @@ func CategorizeEndpoints(endpoints []Endpoint, svcInfo ServicePort, nodeLabels m
 	return
 }
 
-// canUseTopology returns true if all of the following is true:
+// canUseTopology returns true if all of the following are true:
 //   - The node's labels include "topology.kubernetes.io/zone".
 //   - All of the endpoints for this Service have a topology hint.
 //   - At least one endpoint for this Service is hinted for this node's zone.

pkg/proxy/topology_test.go

@@ -23,9 +23,6 @@ import (
 	v1 "k8s.io/api/core/v1"
 	kerrors "k8s.io/apimachinery/pkg/util/errors"
 	"k8s.io/apimachinery/pkg/util/sets"
-	utilfeature "k8s.io/apiserver/pkg/util/feature"
-	featuregatetesting "k8s.io/component-base/featuregate/testing"
-	"k8s.io/kubernetes/pkg/features"
 )
 
 func checkExpectedEndpoints(expected sets.Set[string], actual []Endpoint) error {
@@ -47,12 +44,11 @@ func checkExpectedEndpoints(expected sets.Set[string], actual []Endpoint) error
 
 func TestCategorizeEndpoints(t *testing.T) {
 	testCases := []struct {
-		name         string
+		name        string
-		hintsEnabled bool
+		pteEnabled  bool
-		pteEnabled   bool
+		nodeLabels  map[string]string
-		nodeLabels   map[string]string
+		serviceInfo ServicePort
-		serviceInfo  ServicePort
+		endpoints   []Endpoint
-		endpoints    []Endpoint
 
 		// We distinguish `nil` ("service doesn't use this kind of endpoints") from
 		// `sets.Set[string]()` ("service uses this kind of endpoints but has no endpoints").
@@ -65,10 +61,9 @@ func TestCategorizeEndpoints(t *testing.T) {
 		allEndpoints        sets.Set[string]
 		onlyRemoteEndpoints bool
 	}{{
-		name:         "hints enabled, hints annotation == auto",
+		name:        "should use topology since all endpoints have hints, node has a zone label and and there are endpoints for the node's zone",
-		hintsEnabled: true,
+		nodeLabels:  map[string]string{v1.LabelTopologyZone: "zone-a"},
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
+		serviceInfo: &BaseServicePortInfo{},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "auto"},
 		endpoints: []Endpoint{
 			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
 			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true},
@@ -78,63 +73,9 @@ func TestCategorizeEndpoints(t *testing.T) {
 		clusterEndpoints: sets.New[string]("10.1.2.3:80", "10.1.2.6:80"),
 		localEndpoints:   nil,
 	}, {
-		name:         "hints, hints annotation == disabled, but endpointslice hints are not ignored since trafficDist feature-gate is always enabled by default",
+		name:        "externalTrafficPolicy: Local, topology ignored for Local endpoints",
-		hintsEnabled: true,
+		nodeLabels:  map[string]string{v1.LabelTopologyZone: "zone-a"},
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
+		serviceInfo: &BaseServicePortInfo{externalPolicyLocal: true, nodePort: 8080},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "disabled"},
-		endpoints: []Endpoint{
-			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.5:80", zoneHints: sets.New[string]("zone-c"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.6:80", zoneHints: sets.New[string]("zone-a"), ready: true},
-		},
-		clusterEndpoints: sets.New[string]("10.1.2.3:80", "10.1.2.6:80"),
-		localEndpoints:   nil,
-	}, {
-
-		name:         "hints, hints annotation == aUto (wrong capitalization), hints no longer ignored",
-		hintsEnabled: true,
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "aUto"},
-		endpoints: []Endpoint{
-			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.5:80", zoneHints: sets.New[string]("zone-c"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.6:80", zoneHints: sets.New[string]("zone-a"), ready: true},
-		},
-		clusterEndpoints: sets.New[string]("10.1.2.3:80", "10.1.2.6:80"),
-		localEndpoints:   nil,
-	}, {
-		name:         "hints, hints annotation empty but endpointslice hints are not ignored since trafficDist feature-gate is always enabled by default",
-		hintsEnabled: true,
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
-		serviceInfo:  &BaseServicePortInfo{ /* hints annotation empty */ },
-		endpoints: []Endpoint{
-			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.5:80", zoneHints: sets.New[string]("zone-c"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.6:80", zoneHints: sets.New[string]("zone-a"), ready: true},
-		},
-		clusterEndpoints: sets.New[string]("10.1.2.3:80", "10.1.2.6:80"),
-		localEndpoints:   nil,
-	}, {
-		name:         "hints feature-gate disabled but endpointslice hints are not ignored since trafficDist feature-gate is always enabled by default",
-		hintsEnabled: false,
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
-		serviceInfo:  &BaseServicePortInfo{},
-		endpoints: []Endpoint{
-			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.5:80", zoneHints: sets.New[string]("zone-c"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.6:80", zoneHints: sets.New[string]("zone-a"), ready: true},
-		},
-		clusterEndpoints: sets.New[string]("10.1.2.3:80", "10.1.2.6:80"),
-		localEndpoints:   nil,
-	}, {
-		name:         "externalTrafficPolicy: Local, topology ignored for Local endpoints",
-		hintsEnabled: true,
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
-		serviceInfo:  &BaseServicePortInfo{externalPolicyLocal: true, nodePort: 8080, hintsAnnotation: "auto"},
 		endpoints: []Endpoint{
 			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true, isLocal: true},
 			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true, isLocal: true},
@@ -145,10 +86,9 @@ func TestCategorizeEndpoints(t *testing.T) {
 		localEndpoints:   sets.New[string]("10.1.2.3:80", "10.1.2.4:80"),
 		allEndpoints:     sets.New[string]("10.1.2.3:80", "10.1.2.4:80", "10.1.2.6:80"),
 	}, {
-		name:         "internalTrafficPolicy: Local, topology ignored for Local endpoints",
+		name:        "internalTrafficPolicy: Local, topology ignored for Local endpoints",
-		hintsEnabled: true,
+		nodeLabels:  map[string]string{v1.LabelTopologyZone: "zone-a"},
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
+		serviceInfo: &BaseServicePortInfo{internalPolicyLocal: true, externalPolicyLocal: false, nodePort: 8080},
-		serviceInfo:  &BaseServicePortInfo{internalPolicyLocal: true, hintsAnnotation: "auto", externalPolicyLocal: false, nodePort: 8080},
 		endpoints: []Endpoint{
 			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true, isLocal: true},
 			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true, isLocal: true},
@@ -159,66 +99,48 @@ func TestCategorizeEndpoints(t *testing.T) {
 		localEndpoints:   sets.New[string]("10.1.2.3:80", "10.1.2.4:80"),
 		allEndpoints:     sets.New[string]("10.1.2.3:80", "10.1.2.4:80", "10.1.2.6:80"),
 	}, {
-		name:         "empty node labels",
+		name:        "empty node labels",
-		hintsEnabled: true,
+		nodeLabels:  map[string]string{},
-		nodeLabels:   map[string]string{},
+		serviceInfo: &BaseServicePortInfo{},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "auto"},
 		endpoints: []Endpoint{
 			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
 		},
 		clusterEndpoints: sets.New[string]("10.1.2.3:80"),
 		localEndpoints:   nil,
 	}, {
-		name:         "empty zone label",
+		name:        "empty zone label",
-		hintsEnabled: true,
+		nodeLabels:  map[string]string{v1.LabelTopologyZone: ""},
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: ""},
+		serviceInfo: &BaseServicePortInfo{},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "auto"},
 		endpoints: []Endpoint{
 			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
 		},
 		clusterEndpoints: sets.New[string]("10.1.2.3:80"),
 		localEndpoints:   nil,
 	}, {
-		name:         "node in different zone, no endpoint filtering",
+		name:        "node in different zone, no endpoint filtering",
-		hintsEnabled: true,
+		nodeLabels:  map[string]string{v1.LabelTopologyZone: "zone-b"},
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-b"},
+		serviceInfo: &BaseServicePortInfo{},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "auto"},
 		endpoints: []Endpoint{
 			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
 		},
 		clusterEndpoints: sets.New[string]("10.1.2.3:80"),
 		localEndpoints:   nil,
 	}, {
-		name:         "normal endpoint filtering, auto annotation",
+		name:        "unready endpoint",
-		hintsEnabled: true,
+		nodeLabels:  map[string]string{v1.LabelTopologyZone: "zone-a"},
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
+		serviceInfo: &BaseServicePortInfo{},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "auto"},
 		endpoints: []Endpoint{
 			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
 			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true},
 			&BaseEndpointInfo{endpoint: "10.1.2.5:80", zoneHints: sets.New[string]("zone-c"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.6:80", zoneHints: sets.New[string]("zone-a"), ready: true},
+			&BaseEndpointInfo{endpoint: "10.1.2.6:80", zoneHints: sets.New[string]("zone-a"), ready: false}, // unready
-		},
-		clusterEndpoints: sets.New[string]("10.1.2.3:80", "10.1.2.6:80"),
-		localEndpoints:   nil,
-	}, {
-		name:         "unready endpoint",
-		hintsEnabled: true,
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "auto"},
-		endpoints: []Endpoint{
-			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.5:80", zoneHints: sets.New[string]("zone-c"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.6:80", zoneHints: sets.New[string]("zone-a"), ready: false},
 		},
 		clusterEndpoints: sets.New[string]("10.1.2.3:80"),
 		localEndpoints:   nil,
 	}, {
-		name:         "only unready endpoints in same zone (should not filter)",
+		name:        "only unready endpoints in same zone (should not filter)",
-		hintsEnabled: true,
+		nodeLabels:  map[string]string{v1.LabelTopologyZone: "zone-a"},
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
+		serviceInfo: &BaseServicePortInfo{},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "auto"},
 		endpoints: []Endpoint{
 			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: false},
 			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true},
@@ -228,36 +150,21 @@ func TestCategorizeEndpoints(t *testing.T) {
 		clusterEndpoints: sets.New[string]("10.1.2.4:80", "10.1.2.5:80"),
 		localEndpoints:   nil,
 	}, {
-		name:         "normal endpoint filtering, Auto annotation",
+		name:        "missing hints, no filtering applied",
-		hintsEnabled: true,
+		nodeLabels:  map[string]string{v1.LabelTopologyZone: "zone-a"},
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
+		serviceInfo: &BaseServicePortInfo{},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "Auto"},
 		endpoints: []Endpoint{
 			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
 			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.5:80", zoneHints: sets.New[string]("zone-c"), ready: true},
+			&BaseEndpointInfo{endpoint: "10.1.2.5:80", zoneHints: nil, ready: true}, // Endpoint is missing hint.
-			&BaseEndpointInfo{endpoint: "10.1.2.6:80", zoneHints: sets.New[string]("zone-a"), ready: true},
-		},
-		clusterEndpoints: sets.New[string]("10.1.2.3:80", "10.1.2.6:80"),
-		localEndpoints:   nil,
-	}, {
-		name:         "missing hints, no filtering applied",
-		hintsEnabled: true,
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "auto"},
-		endpoints: []Endpoint{
-			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b"), ready: true},
-			&BaseEndpointInfo{endpoint: "10.1.2.5:80", zoneHints: nil, ready: true},
 			&BaseEndpointInfo{endpoint: "10.1.2.6:80", zoneHints: sets.New[string]("zone-a"), ready: true},
 		},
 		clusterEndpoints: sets.New[string]("10.1.2.3:80", "10.1.2.4:80", "10.1.2.5:80", "10.1.2.6:80"),
 		localEndpoints:   nil,
 	}, {
-		name:         "multiple hints per endpoint, filtering includes any endpoint with zone included",
+		name:        "multiple hints per endpoint, filtering includes any endpoint with zone included",
-		hintsEnabled: true,
+		nodeLabels:  map[string]string{v1.LabelTopologyZone: "zone-c"},
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-c"},
+		serviceInfo: &BaseServicePortInfo{},
-		serviceInfo:  &BaseServicePortInfo{hintsAnnotation: "auto"},
 		endpoints: []Endpoint{
 			&BaseEndpointInfo{endpoint: "10.1.2.3:80", zoneHints: sets.New[string]("zone-a", "zone-b", "zone-c"), ready: true},
 			&BaseEndpointInfo{endpoint: "10.1.2.4:80", zoneHints: sets.New[string]("zone-b", "zone-c"), ready: true},
@@ -267,10 +174,9 @@ func TestCategorizeEndpoints(t *testing.T) {
 		clusterEndpoints: sets.New[string]("10.1.2.3:80", "10.1.2.4:80", "10.1.2.6:80"),
 		localEndpoints:   nil,
 	}, {
-		name:         "conflicting topology and localness require merging allEndpoints",
+		name:        "conflicting topology and localness require merging allEndpoints",
-		hintsEnabled: true,
+		nodeLabels:  map[string]string{v1.LabelTopologyZone: "zone-a"},
-		nodeLabels:   map[string]string{v1.LabelTopologyZone: "zone-a"},
+		serviceInfo: &BaseServicePortInfo{internalPolicyLocal: false, externalPolicyLocal: true, nodePort: 8080},
-		serviceInfo:  &BaseServicePortInfo{internalPolicyLocal: false, externalPolicyLocal: true, nodePort: 8080, hintsAnnotation: "auto"},
 		endpoints: []Endpoint{
 			&BaseEndpointInfo{endpoint: "10.0.0.0:80", zoneHints: sets.New[string]("zone-a"), ready: true, isLocal: true},
 			&BaseEndpointInfo{endpoint: "10.0.0.1:80", zoneHints: sets.New[string]("zone-b"), ready: true, isLocal: true},
@@ -431,8 +337,6 @@ func TestCategorizeEndpoints(t *testing.T) {
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.TopologyAwareHints, tc.hintsEnabled)
-
 			clusterEndpoints, localEndpoints, allEndpoints, hasAnyEndpoints := CategorizeEndpoints(tc.endpoints, tc.serviceInfo, tc.nodeLabels)
 
 			if tc.clusterEndpoints == nil && clusterEndpoints != nil {