Fix condition used for serving and fenced endpoints

Co-authored-by: Kevin Pollet <pollet.kevin@gmail.com>

pkg/provider/kubernetes/crd/kubernetes_http.go

@@ -14,7 +14,6 @@ import (
 	"github.com/traefik/traefik/v3/pkg/observability/logs"
 	"github.com/traefik/traefik/v3/pkg/provider"
 	traefikv1alpha1 "github.com/traefik/traefik/v3/pkg/provider/kubernetes/crd/traefikio/v1alpha1"
-	"github.com/traefik/traefik/v3/pkg/provider/kubernetes/k8s"
 	"github.com/traefik/traefik/v3/pkg/tls"
 	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/util/intstr"
@@ -642,7 +641,10 @@ func (c configBuilder) loadServers(parentNamespace string, svc traefikv1alpha1.L
 		}
 
 		for _, endpoint := range endpointSlice.Endpoints {
-			if !k8s.EndpointServing(endpoint) {
+			// The Serving condition allows to track if the Pod can receive traffic.
+			// It is set to true when the Pod is Ready or Terminating.
+			// From the go documentation, a nil value should be interpreted as "true".
+			if !ptr.Deref(endpoint.Conditions.Serving, true) {
 				continue
 			}
 
@@ -654,7 +656,7 @@ func (c configBuilder) loadServers(parentNamespace string, svc traefikv1alpha1.L
 				addresses[address] = struct{}{}
 				servers = append(servers, dynamic.Server{
 					URL:    fmt.Sprintf("%s://%s", protocol, net.JoinHostPort(address, strconv.Itoa(int(port)))),
-					Fenced: ptr.Deref(endpoint.Conditions.Terminating, false) && ptr.Deref(endpoint.Conditions.Serving, false),
+					Fenced: ptr.Deref(endpoint.Conditions.Terminating, false),
 				})
 			}
 		}

pkg/provider/kubernetes/ingress-nginx/kubernetes.go

@@ -22,7 +22,6 @@ import (
 	"github.com/traefik/traefik/v3/pkg/job"
 	"github.com/traefik/traefik/v3/pkg/observability/logs"
 	"github.com/traefik/traefik/v3/pkg/provider"
-	"github.com/traefik/traefik/v3/pkg/provider/kubernetes/k8s"
 	"github.com/traefik/traefik/v3/pkg/safe"
 	"github.com/traefik/traefik/v3/pkg/tls"
 	"github.com/traefik/traefik/v3/pkg/types"
@@ -646,7 +645,10 @@ func (p *Provider) getBackendAddresses(namespace string, backend netv1.IngressBa
 		}
 
 		for _, endpoint := range endpointSlice.Endpoints {
-			if !k8s.EndpointServing(endpoint) {
+			// The Serving condition allows to track if the Pod can receive traffic.
+			// It is set to true when the Pod is Ready or Terminating.
+			// From the go documentation, a nil value should be interpreted as "true".
+			if !ptr.Deref(endpoint.Conditions.Serving, true) {
 				continue
 			}
 
@@ -658,7 +660,7 @@ func (p *Provider) getBackendAddresses(namespace string, backend netv1.IngressBa
 				uniqAddresses[address] = struct{}{}
 				addresses = append(addresses, backendAddress{
 					Address: net.JoinHostPort(address, strconv.Itoa(int(port))),
-					Fenced:  ptr.Deref(endpoint.Conditions.Terminating, false) && ptr.Deref(endpoint.Conditions.Serving, false),
+					Fenced:  ptr.Deref(endpoint.Conditions.Terminating, false),
 				})
 			}
 		}

pkg/provider/kubernetes/ingress/kubernetes.go

@@ -662,7 +662,10 @@ func (p *Provider) loadService(client Client, namespace string, backend netv1.In
 		protocol := getProtocol(portSpec, portName, svcConfig)
 
 		for _, endpoint := range endpointSlice.Endpoints {
-			if !k8s.EndpointServing(endpoint) {
+			// The Serving condition allows to track if the Pod can receive traffic.
+			// It is set to true when the Pod is Ready or Terminating.
+			// From the go documentation, a nil value should be interpreted as "true".
+			if !ptr.Deref(endpoint.Conditions.Serving, true) {
 				continue
 			}
 
@@ -674,7 +677,7 @@ func (p *Provider) loadService(client Client, namespace string, backend netv1.In
 				addresses[address] = struct{}{}
 				svc.LoadBalancer.Servers = append(svc.LoadBalancer.Servers, dynamic.Server{
 					URL:    fmt.Sprintf("%s://%s", protocol, net.JoinHostPort(address, strconv.Itoa(int(port)))),
-					Fenced: ptr.Deref(endpoint.Conditions.Terminating, false) && ptr.Deref(endpoint.Conditions.Serving, false),
+					Fenced: ptr.Deref(endpoint.Conditions.Terminating, false),
 				})
 			}
 		}

pkg/provider/kubernetes/k8s/endpoint.go

@@ -1,11 +0,0 @@
-package k8s
-
-import (
-	v1 "k8s.io/api/discovery/v1"
-	"k8s.io/utils/ptr"
-)
-
-// EndpointServing returns true if the endpoint is still serving the service.
-func EndpointServing(endpoint v1.Endpoint) bool {
-	return ptr.Deref(endpoint.Conditions.Ready, false) || ptr.Deref(endpoint.Conditions.Serving, false)
-}

pkg/provider/kubernetes/k8s/endpoint_test.go

@@ -1,75 +0,0 @@
-package k8s
-
-import (
-	"testing"
-
-	"github.com/stretchr/testify/assert"
-	v1 "k8s.io/api/discovery/v1"
-)
-
-func TestEndpointServing(t *testing.T) {
-	tests := []struct {
-		name     string
-		endpoint v1.Endpoint
-		want     bool
-	}{
-		{
-			name: "no status",
-			endpoint: v1.Endpoint{
-				Conditions: v1.EndpointConditions{
-					Ready:   nil,
-					Serving: nil,
-				},
-			},
-			want: false,
-		},
-		{
-			name: "ready",
-			endpoint: v1.Endpoint{
-				Conditions: v1.EndpointConditions{
-					Ready:   pointer(true),
-					Serving: nil,
-				},
-			},
-			want: true,
-		},
-		{
-			name: "not ready",
-			endpoint: v1.Endpoint{
-				Conditions: v1.EndpointConditions{
-					Ready:   pointer(false),
-					Serving: nil,
-				},
-			},
-			want: false,
-		},
-		{
-			name: "not ready and serving",
-			endpoint: v1.Endpoint{
-				Conditions: v1.EndpointConditions{
-					Ready:   pointer(false),
-					Serving: pointer(true),
-				},
-			},
-			want: true,
-		},
-		{
-			name: "not ready and not serving",
-			endpoint: v1.Endpoint{
-				Conditions: v1.EndpointConditions{
-					Ready:   pointer(false),
-					Serving: pointer(false),
-				},
-			},
-			want: false,
-		},
-	}
-	for _, test := range tests {
-		t.Run(test.name, func(t *testing.T) {
-			got := EndpointServing(test.endpoint)
-			assert.Equal(t, test.want, got)
-		})
-	}
-}
-
-func pointer[T any](v T) *T { return &v }