type PortList []*Port

// TrafficDirection defines whether traffic exists a service instance or enters a service instance
type TrafficDirection string

const (
	// TrafficDirectionInbound indicates inbound traffic
	TrafficDirectionInbound TrafficDirection = "inbound"
	// TrafficDirectionInboundVIP indicates inbound traffic for vip
	TrafficDirectionInboundVIP TrafficDirection = "inbound-vip"

	l := &listener.Listener{
		Name:                             MainInternalName,
		ListenerSpecifier:                &listener.Listener_InternalListener{InternalListener: &listener.Listener_InternalListenerConfig{}},
		TrafficDirection:                 core.TrafficDirection_INBOUND,
		ContinueOnListenerFiltersTimeout: true,
	}

	// Flush authz cache since we need filter state for the principal.
	oldBuilder := lb.authzBuilder

// It is used for building both inbound and outbound cluster.
func (cb *ClusterBuilder) buildCluster(name string, discoveryType cluster.Cluster_DiscoveryType,
	localityLbEndpoints []*endpoint.LocalityLbEndpoints, direction model.TrafficDirection,
	port *model.Port, service *model.Service, inboundServices []model.ServiceTarget,
	subset string,
) *clusterWrapper {
	c := &cluster.Cluster{
		Name:                 name,

	} else {
		sc.configDependencies.InsertAll(dependencies...)
	}
}

// DestinationRule returns a destinationrule for a svc.
func (sc *SidecarScope) DestinationRule(direction TrafficDirection, proxy *Proxy, svc host.Name) *ConsolidatedDestRule {
	destinationRules := sc.destinationRules[svc]
	var catchAllDr *ConsolidatedDestRule
	for _, destRule := range destinationRules {

			xdsfilters.OriginalDestination,
			// TODO: This may affect the data path due to the server-first protocols triggering a time-out. Need exception filter.
			xdsfilters.HTTPInspector,
		},
		TrafficDirection: core.TrafficDirection_INBOUND,
		FilterChains:     chains,
		FilterChainMatcher: &matcher.Matcher{
			MatcherType: &matcher.Matcher_MatcherTree_{
				MatcherTree: &matcher.Matcher_MatcherTree{

	// the east-west gateway in a remote cluster will use this value to route
	// traffic to the appropriate service
	istioMtlsSni    string
	clusterMode     ClusterMode
	direction       model.TrafficDirection
	meshExternal    bool
	serviceMTLSMode model.MutualTLSMode
	// Indicates the service registry of the cluster being built.
	serviceRegistry provider.ID
	// Indicates if the destinationRule has a workloadSelector

	}

	cases := []struct {
		name            string
		clusterName     string
		discovery       cluster.Cluster_DiscoveryType
		endpoints       []*endpoint.LocalityLbEndpoints
		direction       model.TrafficDirection
		external        bool
		expectedCluster *cluster.Cluster
	}{
		{
			name:        "default EDS cluster",
			clusterName: "foo",
			discovery:   cluster.Cluster_EDS,
			endpoints:   nil,

				t.Fatalf("want %v got %v", tt.want, clusterNames)
			}
		})
	}
}

func TestTelemetryMetadata(t *testing.T) {
	cases := []struct {
		name      string
		direction model.TrafficDirection
		cluster   *cluster.Cluster
		svcInsts  []model.ServiceTarget
		service   *model.Service
		want      *core.Metadata
	}{
		{
			name:      "no cluster",