fix svc long name

internal/ingress/controller/store/endpointslice.go

@@ -21,6 +21,7 @@ import (
 	"strings"
 
 	discoveryv1 "k8s.io/api/discovery/v1"
+	apiNames "k8s.io/apiserver/pkg/storage/names"
 	"k8s.io/client-go/tools/cache"
 )
 
@@ -32,9 +33,21 @@ type EndpointSliceLister struct {
 // MatchByKey returns the EndpointsSlices of the Service matching key in the local Endpoint Store.
 func (s *EndpointSliceLister) MatchByKey(key string) ([]*discoveryv1.EndpointSlice, error) {
 	var eps []*discoveryv1.EndpointSlice
+	keyNsLen := strings.Index(key, "/")
+	if keyNsLen < -1 {
+		keyNsLen = 0
+	} else {
+		// count '/' char
+		keyNsLen += 1
+	}
 	// filter endpointSlices owned by svc
 	for _, listKey := range s.ListKeys() {
-		if !strings.HasPrefix(listKey, key) {
+		if len(key) < (apiNames.MaxGeneratedNameLength+keyNsLen) && !strings.HasPrefix(listKey, key) {
+			continue
+		}
+		// generated endpointslices names has truncated svc name as prefix when svc name is too long, we compare only non truncated part
+		// https://github.com/kubernetes/ingress-nginx/issues/9240
+		if len(key) >= (apiNames.MaxGeneratedNameLength+keyNsLen) && !strings.HasPrefix(listKey, key[:apiNames.MaxGeneratedNameLength+keyNsLen-1]) {
 			continue
 		}
 		epss, exists, err := s.GetByKey(listKey)

internal/ingress/controller/store/endpointslice_test.go

@@ -17,6 +17,7 @@ limitations under the License.
 package store
 
 import (
+	"fmt"
 	"testing"
 
 	discoveryv1 "k8s.io/api/discovery/v1"
@@ -91,4 +92,42 @@ func TestEndpointSliceLister(t *testing.T) {
 			t.Errorf("expected %v, error, got %v", endpointSlice.GetName(), eps[0].GetName())
 		}
 	})
+	t.Run("svc long name", func(t *testing.T) {
+		el := newEndpointSliceLister(t)
+		ns := "namespace"
+		ns2 := "another-ns"
+		svcName := "test-backend-http-test-http-test-http-test-http-test-http-truncated"
+		svcName2 := "another-long-svc-name-for-test-inhttp-test-http-test-http-truncated"
+		key := fmt.Sprintf("%s/%s", ns, svcName)
+		endpointSlice := &discoveryv1.EndpointSlice{
+			ObjectMeta: metav1.ObjectMeta{
+				Namespace: ns,
+				Name:      "test-backend-http-test-http-test-http-test-http-test-http-bar88",
+				Labels: map[string]string{
+					discoveryv1.LabelServiceName: svcName,
+				},
+			},
+		}
+		el.Add(endpointSlice)
+		endpointSlice2 := &discoveryv1.EndpointSlice{
+			ObjectMeta: metav1.ObjectMeta{
+				Namespace: ns2,
+				Name:      "another-long-svc-name-for-test-inhttp-test-http-test-http-bar88",
+				Labels: map[string]string{
+					discoveryv1.LabelServiceName: svcName2,
+				},
+			},
+		}
+		el.Add(endpointSlice2)
+		eps, err := el.MatchByKey(key)
+		if err != nil {
+			t.Errorf("unexpeted error %v", err)
+		}
+		if len(eps) != 1 {
+			t.Errorf("expected one slice %v, error, got %d slices", endpointSlice, len(eps))
+		}
+		if len(eps) == 1 && eps[0].Labels[discoveryv1.LabelServiceName] != svcName {
+			t.Errorf("expected slice %v, error, got %v slices", endpointSlice, eps[0])
+		}
+	})
 }

test/e2e/e2e.go

@@ -34,6 +34,7 @@ import (
 	_ "k8s.io/ingress-nginx/test/e2e/annotations/modsecurity"
 	_ "k8s.io/ingress-nginx/test/e2e/dbg"
 	_ "k8s.io/ingress-nginx/test/e2e/defaultbackend"
+	_ "k8s.io/ingress-nginx/test/e2e/endpointslices"
 	_ "k8s.io/ingress-nginx/test/e2e/gracefulshutdown"
 	_ "k8s.io/ingress-nginx/test/e2e/ingress"
 	_ "k8s.io/ingress-nginx/test/e2e/leaks"

test/e2e/endpointslices/longname.go

@@ -0,0 +1,55 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package endpointslices
+
+import (
+	"fmt"
+	"net/http"
+	"strings"
+
+	"github.com/onsi/ginkgo/v2"
+
+	"k8s.io/ingress-nginx/test/e2e/framework"
+)
+
+var _ = framework.IngressNginxDescribe("[Endpointslices] long service name", func() {
+	f := framework.NewDefaultFramework("endpointslices")
+	host := "longsvcname.foo.com"
+	name := "long-name-foobar-foobar-foobar-foobar-foobar-bar-foo-bar-foobuz"
+
+	ginkgo.BeforeEach(func() {
+		f.NewEchoDeployment(framework.WithName(name))
+	})
+
+	ginkgo.It("should return 200 when service name has max allowed number of characters 63", func() {
+
+		annotations := make(map[string]string)
+		ing := framework.NewSingleIngress(host, "/", host, f.Namespace, name, 80, annotations)
+		f.EnsureIngress(ing)
+
+		f.WaitForNginxServer(host, func(server string) bool {
+			return strings.Contains(server, fmt.Sprintf("server_name %s", host))
+		})
+
+		ginkgo.By("checking if the service is reached")
+		f.HTTPTestClient().
+			GET("/").
+			WithHeader("Host", host).
+			Expect().
+			Status(http.StatusOK)
+	})
+})

test/e2e/framework/deployment.go

@@ -67,6 +67,12 @@ func WithDeploymentReplicas(r int) func(*deploymentOptions) {
 	}
 }
 
+func WithName(n string) func(*deploymentOptions) {
+	return func(o *deploymentOptions) {
+		o.name = n
+	}
+}
+
 // NewEchoDeployment creates a new single replica deployment of the echo server image in a particular namespace
 func (f *Framework) NewEchoDeployment(opts ...func(*deploymentOptions)) {
 	options := &deploymentOptions{