[v18] Add health checks to Kubernetes

api/proto/teleport/healthcheckconfig/v1/health_check_config.proto

@@ -64,4 +64,13 @@ message Matcher {
   // empty value is ignored. The match result is logically ANDed with DBLabels,
   // if both are non-empty.
   string db_labels_expression = 2;
+  // KubernetesLabels matches Kubernetes labels. An empty value is ignored. The match
+  // result is logically ANDed with KubernetesLabelsExpression, if both are non-empty.
+  repeated teleport.label.v1.Label kubernetes_labels = 3;
+  // KubernetesLabelsExpression is a label predicate expression to match Kubernetes. An
+  // empty value is ignored. The match result is logically ANDed with KubernetesLabels,
+  // if both are non-empty.
+  string kubernetes_labels_expression = 4;
+  // Disabled disables matches for all labels and expressions.
+  bool disabled = 5;
 }

api/proto/teleport/legacy/types/types.proto

@@ -5167,6 +5167,7 @@ message KubernetesClusterV3List {
 message KubernetesServerV3 {
   option (gogoproto.goproto_stringer) = false;
   option (gogoproto.stringer) = false;
+
   // Kind is the Kubernetes server resource kind. Always "kube_server".
   string Kind = 1 [(gogoproto.jsontag) = "kind"];
   // SubKind is an optional resource subkind.
@@ -5183,6 +5184,8 @@ message KubernetesServerV3 {
     (gogoproto.nullable) = false,
     (gogoproto.jsontag) = "spec"
   ];
+  // Status is the Kubernetes server status.
+  KubernetesServerStatusV3 status = 6;
 }
 
 // KubernetesServerSpecV3 is the Kubernetes server spec.
@@ -5209,6 +5212,13 @@ message KubernetesServerSpecV3 {
   repeated string relay_ids = 8;
 }
 
+// KubernetesServerStatusV3 is the Kubernetes cluster status.
+message KubernetesServerStatusV3 {
+  // TargetHealth is the health status of between the Teleport agent
+  // and Kubernetes cluster.
+  TargetHealth target_health = 1;
+}
+
 // WebTokenV3 describes a web token. Web tokens are used as a transport to relay bearer tokens
 // to the client.
 // Initially bound to a web session, these have been factored out into a separate resource to

api/types/kubernetes_server.go

@@ -58,6 +58,14 @@ type KubeServer interface {
 	SetCluster(KubeCluster) error
 	// ProxiedService provides common methods for a proxied service.
 	ProxiedService
+	// GetTargetHealth gets health details for a target Kubernetes cluster.
+	GetTargetHealth() *TargetHealth
+	// SetTargetHealth sets health details for a target Kubernetes cluster.
+	SetTargetHealth(h *TargetHealth)
+	// GetTargetHealthStatus gets the health status of a target Kubernetes cluster.
+	GetTargetHealthStatus() TargetHealthStatus
+	// SetTargetHealthStatus sets the health status of a target Kubernetes cluster.
+	SetTargetHealthStatus(status TargetHealthStatus)
 	// GetRelayGroup returns the name of the Relay group that the kube server is
 	// connected to.
 	GetRelayGroup() string
@@ -331,6 +339,55 @@ func (k *KubernetesServerV3) IsEqual(i KubeServer) bool {
 	return false
 }
 
+// GetTargetHealth gets health details for a target Kubernetes cluster.
+func (s *KubernetesServerV3) GetTargetHealth() *TargetHealth {
+	return s.GetStatus().GetTargetHealth()
+}
+
+// SetTargetHealth sets health details for a target Kubernetes cluster.
+func (s *KubernetesServerV3) SetTargetHealth(h *TargetHealth) {
+	if s.Status == nil {
+		s.Status = &KubernetesServerStatusV3{}
+	}
+	s.Status.TargetHealth = h
+}
+
+// GetTargetHealthStatus gets the health status of a target Kubernetes cluster.
+func (s *KubernetesServerV3) GetTargetHealthStatus() TargetHealthStatus {
+	health := s.GetStatus().GetTargetHealth()
+	if health == nil {
+		return TargetHealthStatusUnknown
+	}
+	return TargetHealthStatus(health.Status)
+}
+
+// SetTargetHealthStatus sets the health status of a target Kubernetes cluster.
+func (s *KubernetesServerV3) SetTargetHealthStatus(status TargetHealthStatus) {
+	if s.Status == nil {
+		s.Status = &KubernetesServerStatusV3{}
+	}
+	if s.Status.TargetHealth == nil {
+		s.Status.TargetHealth = &TargetHealth{}
+	}
+	s.Status.TargetHealth.Status = string(status)
+}
+
+// GetStatus gets the Kubernetes server status.
+func (s *KubernetesServerV3) GetStatus() *KubernetesServerStatusV3 {
+	if s == nil {
+		return nil
+	}
+	return s.Status
+}
+
+// GetTargetHealth gets the health of a Kubernetes cluster.
+func (s *KubernetesServerStatusV3) GetTargetHealth() *TargetHealth {
+	if s == nil {
+		return nil
+	}
+	return s.TargetHealth
+}
+
 // KubeServers represents a list of kube servers.
 type KubeServers []KubeServer
 

api/types/target_health.go

@@ -25,8 +25,10 @@ import (
 type TargetHealthProtocol string
 
 const (
-	// TargetHealthProtocolTCP is a target health check protocol.
-	TargetHealthProtocolTCP TargetHealthProtocol = "TCP"
+	// TargetHealthProtocolTCP is the TCP target health check protocol.
+	TargetHealthProtocolTCP TargetHealthProtocol = "tcp"
+	// TargetHealthProtocolHTTP is the HTTP target health check protocol.
+	TargetHealthProtocolHTTP TargetHealthProtocol = "http"
 )
 
 // TargetHealthStatus is a target resource's health status.