Add API for feature gate ServiceTopology

api/api-rules/violation_exceptions.list

@@ -214,6 +214,7 @@ API rule violation: list_type_missing,k8s.io/api/core/v1,ServiceAccountList,Item
 API rule violation: list_type_missing,k8s.io/api/core/v1,ServiceList,Items
 API rule violation: list_type_missing,k8s.io/api/core/v1,ServiceSpec,ExternalIPs
 API rule violation: list_type_missing,k8s.io/api/core/v1,ServiceSpec,LoadBalancerSourceRanges
+API rule violation: list_type_missing,k8s.io/api/core/v1,ServiceSpec,TopologyKeys
 API rule violation: list_type_missing,k8s.io/api/core/v1,TopologySelectorLabelRequirement,Values
 API rule violation: list_type_missing,k8s.io/api/core/v1,TopologySelectorTerm,MatchLabelExpressions
 API rule violation: list_type_missing,k8s.io/api/events/v1beta1,EventList,Items

pkg/apis/core/types.go

@@ -3503,6 +3503,21 @@ type ServiceSpec struct {
 	// cluster (e.g. IPv6 in IPv4 only cluster) is an error condition and will fail during clusterIP assignment.
 	// +optional
 	IPFamily *IPFamily
+
+	// topologyKeys is a preference-order list of topology keys which
+	// implementations of services should use to preferentially sort endpoints
+	// when accessing this Service. Topology keys must be valid label keys and
+	// at most 16 keys may be specified.
+	// If any ready backends exist for index [0], they should always be chosen;
+	// only if no backends exist for index [0] should backends for index [1] be considered.
+	// If this field is specified and all entries have no backends that match
+	// the topology of the client, the service has no backends for that client
+	// and connections should fail.
+	// The special value "" may be used to mean "any node". This catch-all
+	// value, if used, only makes sense as the last value in the list.
+	// If this is not specified or empty, no topology constraints will be applied.
+	// +optional
+	TopologyKeys []string
 }
 
 // ServicePort represents the port on which the service is exposed

pkg/features/kube_features.go

@@ -538,6 +538,12 @@ const (
 	//
 	// Enable all logic related to the PodDisruptionBudget API object in policy
 	PodDisruptionBudget featuregate.Feature = "PodDisruptionBudget"
+
+	// owner: @m1093782566
+	// alpha: v1.17
+	//
+	// Enables topology aware service routing
+	ServiceTopology featuregate.Feature = "ServiceTopology"
 )
 
 func init() {
@@ -623,6 +629,7 @@ var defaultKubernetesFeatureGates = map[featuregate.Feature]featuregate.FeatureS
 	StartupProbe:                                   {Default: false, PreRelease: featuregate.Alpha},
 	AllowInsecureBackendProxy:                      {Default: true, PreRelease: featuregate.Beta},
 	PodDisruptionBudget:                            {Default: true, PreRelease: featuregate.Beta},
+	ServiceTopology:                                {Default: false, PreRelease: featuregate.Alpha},
 
 	// inherited features from generic apiserver, relisted here to get a conflict if it is changed
 	// unintentionally on either side:

staging/src/k8s.io/api/core/v1/types.go

@@ -3940,6 +3940,7 @@ type ServiceSpec struct {
 	// of peer discovery.
 	// +optional
 	PublishNotReadyAddresses bool `json:"publishNotReadyAddresses,omitempty" protobuf:"varint,13,opt,name=publishNotReadyAddresses"`
+
 	// sessionAffinityConfig contains the configurations of session affinity.
 	// +optional
 	SessionAffinityConfig *SessionAffinityConfig `json:"sessionAffinityConfig,omitempty" protobuf:"bytes,14,opt,name=sessionAffinityConfig"`
@@ -3953,6 +3954,21 @@ type ServiceSpec struct {
 	// cluster (e.g. IPv6 in IPv4 only cluster) is an error condition and will fail during clusterIP assignment.
 	// +optional
 	IPFamily *IPFamily `json:"ipFamily,omitempty" protobuf:"bytes,15,opt,name=ipFamily,Configcasttype=IPFamily"`
+
+	// topologyKeys is a preference-order list of topology keys which
+	// implementations of services should use to preferentially sort endpoints
+	// when accessing this Service. Topology keys must be valid label keys and
+	// at most 16 keys may be specified.
+	// If any ready backends exist for index [0], they should always be chosen;
+	// only if no backends exist for index [0] should backends for index [1] be considered.
+	// If this field is specified and all entries have no backends that match
+	// the topology of the client, the service has no backends for that client
+	// and connections should fail.
+	// The special value "" may be used to mean "any node". This catch-all
+	// value, if used, only makes sense as the last value in the list.
+	// If this is not specified or empty, no topology constraints will be applied.
+	// +optional
+	TopologyKeys []string `json:"topologyKeys,omitempty" protobuf:"bytes,15,opt,name=topologyKeys"`
 }
 
 // ServicePort contains information on service's port.