Service Topology implementation

* Implement Service Topology for ipvs and iptables proxier
* Add test files
* API validation

pkg/apis/core/validation/validation_test.go

@@ -18,6 +18,7 @@ package validation
 
 import (
 	"bytes"
+	"fmt"
 	"math"
 	"reflect"
 	"strings"
@@ -9380,6 +9381,7 @@ func TestValidatePodEphemeralContainersUpdate(t *testing.T) {
 
 func TestValidateService(t *testing.T) {
 	defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.SCTPSupport, true)()
+	defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, features.ServiceTopology, true)()
 
 	testCases := []struct {
 		name     string
@@ -10058,6 +10060,66 @@ func TestValidateService(t *testing.T) {
 			},
 			numErrs: 1,
 		},
+		{
+			name: "valid topology keys",
+			tweakSvc: func(s *core.Service) {
+				s.Spec.TopologyKeys = []string{
+					"kubernetes.io/hostname",
+					"failure-domain.beta.kubernetes.io/zone",
+					"failure-domain.beta.kubernetes.io/region",
+					v1.TopologyKeyAny,
+				}
+			},
+			numErrs: 0,
+		},
+		{
+			name: "invalid topology key",
+			tweakSvc: func(s *core.Service) {
+				s.Spec.TopologyKeys = []string{"NoUppercaseOrSpecialCharsLike=Equals"}
+			},
+			numErrs: 1,
+		},
+		{
+			name: "too many topology keys",
+			tweakSvc: func(s *core.Service) {
+				for i := 0; i < core.MaxServiceTopologyKeys+1; i++ {
+					s.Spec.TopologyKeys = append(s.Spec.TopologyKeys, fmt.Sprintf("topologykey-%d", i))
+				}
+			},
+			numErrs: 1,
+		},
+		{
+			name: `"Any" was not the last key`,
+			tweakSvc: func(s *core.Service) {
+				s.Spec.TopologyKeys = []string{
+					"kubernetes.io/hostname",
+					v1.TopologyKeyAny,
+					"failure-domain.beta.kubernetes.io/zone",
+				}
+			},
+			numErrs: 1,
+		},
+		{
+			name: `duplicate topology key`,
+			tweakSvc: func(s *core.Service) {
+				s.Spec.TopologyKeys = []string{
+					"kubernetes.io/hostname",
+					"kubernetes.io/hostname",
+					"failure-domain.beta.kubernetes.io/zone",
+				}
+			},
+			numErrs: 1,
+		},
+		{
+			name: `use topology keys with externalTrafficPolicy=Local`,
+			tweakSvc: func(s *core.Service) {
+				s.Spec.ExternalTrafficPolicy = "Local"
+				s.Spec.TopologyKeys = []string{
+					"kubernetes.io/hostname",
+				}
+			},
+			numErrs: 2,
+		},
 	}
 
 	for _, tc := range testCases {