✨ make APIExportEndpointSlice consumer aware

Makefile

@@ -336,6 +336,20 @@ test-e2e-sharded-minimal: build-all
 		$(SUITES_ARGS) \
 	$(if $(value WAIT),|| { echo "Terminated with $$?"; wait "$$PID"; },)
 
+# This is just easy target to run 2 shard test server locally until manually killed.
+# You can targer test to it by running:
+# go test ./test/e2e/apibinding/... --kcp-kubeconfig=$(pwd)/.kcp/admin.kubeconfig --shard-kubeconfigs=root=$(pwd)/.kcp-0/admin.kubeconfig -run=^TestAPIBindingEndpointSlicesSharded$
+test-run-sharded-server: WORK_DIR ?= .
+test-run-sharded-server: LOG_DIR ?= $(WORK_DIR)/.kcp
+test-run-sharded-server:
+	mkdir -p "$(LOG_DIR)" "$(WORK_DIR)/.kcp"
+	rm -f "$(WORK_DIR)/.kcp/ready-to-test"
+	UNSAFE_E2E_HACK_DISABLE_ETCD_FSYNC=true NO_GORUN=1 ./bin/sharded-test-server --quiet --v=2 --log-dir-path="$(LOG_DIR)" --work-dir-path="$(WORK_DIR)" --shard-run-virtual-workspaces=false --shard-feature-gates=$(TEST_FEATURE_GATES) $(TEST_SERVER_ARGS) --number-of-shards=2 2>&1 & PID=$$!; echo "PID $$PID" && \
+	trap 'kill -TERM $$PID' TERM INT EXIT && \
+	while [ ! -f "$(WORK_DIR)/.kcp/ready-to-test" ]; do sleep 1; done && \
+	echo 'Server started' && \
+	wait $$PID
+
 .PHONY: test
 ifdef USE_GOTESTSUM
 test: $(GOTESTSUM)

config/crds/apis.kcp.io_apiexportendpointslices.yaml

@@ -148,6 +148,15 @@ spec:
                   - url
                   type: object
                 type: array
+                x-kubernetes-list-map-keys:
+                - url
+                x-kubernetes-list-type: map
+              shardSelector:
+                description: |-
+                  shardSelector is the selector used to filter the shards. It is used to filter the shards
+                  when determining partition scope when deriving the endpoints. This is set by owning shard,
+                  and is used by follower shards to determine if its inscope or not.
+                type: string
             type: object
         type: object
     served: true

pkg/authorization/bootstrap/policy.go

@@ -24,6 +24,7 @@ import (
 	rbacrest "k8s.io/kubernetes/pkg/registry/rbac/rest"
 	"k8s.io/kubernetes/plugin/pkg/auth/authorizer/rbac/bootstrappolicy"
 
+	"github.com/kcp-dev/kcp/sdk/apis/apis"
 	"github.com/kcp-dev/kcp/sdk/apis/core"
 	"github.com/kcp-dev/kcp/sdk/apis/tenancy"
 )
@@ -101,6 +102,13 @@ func clusterRoles() []rbacv1.ClusterRole {
 				rbacv1helpers.NewRule("access").URLs("/").RuleOrDie(),
 			},
 		},
+		{
+			ObjectMeta: metav1.ObjectMeta{Name: SystemExternalLogicalClusterAdmin},
+			Rules: []rbacv1.PolicyRule{
+				rbacv1helpers.NewRule("update", "patch", "get").Groups(apis.GroupName).Resources("apiexportendpointslices/status").RuleOrDie(),
+				rbacv1helpers.NewRule("get", "list", "watch").Groups(apis.GroupName).Resources("apiexportendpointslices").RuleOrDie(),
+			},
+		},
 	}
 }
 

pkg/indexers/apiexport.go

@@ -17,6 +17,8 @@ limitations under the License.
 package indexers
 
 import (
+	"fmt"
+
 	kcpcache "github.com/kcp-dev/apimachinery/v2/pkg/cache"
 	"github.com/kcp-dev/logicalcluster/v3"
 
@@ -33,6 +35,8 @@ const (
 	// APIExportByClaimedIdentities is the indexer name for retrieving APIExports that have a permission claim for a
 	// particular identity hash.
 	APIExportByClaimedIdentities = "APIExportByClaimedIdentities"
+	// APIExportEndpointSliceByAPIExport is the indexer name for retrieving APIExportEndpointSlices by their APIExport's Reference Path and Name.
+	APIExportEndpointSliceByAPIExport = "APIExportEndpointSliceByAPIExport"
 )
 
 // IndexAPIExportByIdentity is an index function that indexes an APIExport by its identity hash.
@@ -72,3 +76,23 @@ func IndexAPIExportByClaimedIdentities(obj interface{}) ([]string, error) {
 	}
 	return sets.List[string](claimedIdentities), nil
 }
+
+// IndexAPIExportEndpointSliceByAPIExportFunc indexes the APIExportEndpointSlice by their APIExport's Reference Path and Name.
+func IndexAPIExportEndpointSliceByAPIExport(obj interface{}) ([]string, error) {
+	apiExportEndpointSlice, ok := obj.(*apisv1alpha1.APIExportEndpointSlice)
+	if !ok {
+		return []string{}, fmt.Errorf("obj %T is not an APIExportEndpointSlice", obj)
+	}
+
+	var result []string
+	pathRemote := logicalcluster.NewPath(apiExportEndpointSlice.Spec.APIExport.Path)
+	if !pathRemote.Empty() {
+		result = append(result, pathRemote.Join(apiExportEndpointSlice.Spec.APIExport.Name).String())
+	}
+	pathLocal := logicalcluster.From(apiExportEndpointSlice).Path()
+	if !pathLocal.Empty() {
+		result = append(result, pathLocal.Join(apiExportEndpointSlice.Spec.APIExport.Name).String())
+	}
+
+	return result, nil
+}

pkg/indexers/apiexport_test.go

@@ -0,0 +1,95 @@
+/*
+Copyright 2025 The KCP 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 indexers
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/kcp-dev/logicalcluster/v3"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+
+	apisv1alpha1 "github.com/kcp-dev/kcp/sdk/apis/apis/v1alpha1"
+)
+
+func TestIndexAPIExportEndpointSliceByAPIExport(t *testing.T) {
+	tests := map[string]struct {
+		obj     interface{}
+		want    []string
+		wantErr bool
+	}{
+		"not an APIExportEndpointSlice": {
+			obj:     "not an APIExportEndpointSlice",
+			want:    []string{},
+			wantErr: true,
+		},
+		"valid APIExportEndpointSlice": {
+			obj: &apisv1alpha1.APIExportEndpointSlice{
+				ObjectMeta: metav1.ObjectMeta{
+					Annotations: map[string]string{
+						logicalcluster.AnnotationKey: "root:local",
+					},
+					Name: "foo",
+				},
+				Spec: apisv1alpha1.APIExportEndpointSliceSpec{
+					APIExport: apisv1alpha1.ExportBindingReference{
+						Path: "root:default",
+						Name: "foo",
+					},
+				},
+			},
+			want: []string{
+				logicalcluster.NewPath("root:default:foo").String(),
+				logicalcluster.NewPath("root:local:foo").String(),
+			},
+			wantErr: false,
+		},
+		"valid APIExportEndpointSlice local to export": {
+			obj: &apisv1alpha1.APIExportEndpointSlice{
+				ObjectMeta: metav1.ObjectMeta{
+					Annotations: map[string]string{
+						logicalcluster.AnnotationKey: "root:local",
+					},
+					Name: "foo",
+				},
+				Spec: apisv1alpha1.APIExportEndpointSliceSpec{
+					APIExport: apisv1alpha1.ExportBindingReference{
+						Name: "foo",
+					},
+				},
+			},
+			want: []string{
+				logicalcluster.NewPath("root:local:foo").String(),
+			},
+			wantErr: false,
+		},
+	}
+
+	for name, tt := range tests {
+		t.Run(name, func(t *testing.T) {
+			got, err := IndexAPIExportEndpointSliceByAPIExport(tt.obj)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("IndexAPIExportEndpointSliceByAPIExport() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("IndexAPIExportEndpointSliceByAPIExport() got = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}