Adding EndpointSliceMirroring controller

This will mirror custom Endpoints to EndpointSlices to ensure that
applications will not need to maintain both separately.

pkg/controller/endpointslicemirroring/endpointslice_tracker_test.go

@@ -0,0 +1,174 @@
+/*
+Copyright 2020 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 endpointslicemirroring
+
+import (
+	"testing"
+
+	discovery "k8s.io/api/discovery/v1beta1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+)
+
+func TestEndpointSliceTrackerUpdate(t *testing.T) {
+	epSlice1 := &discovery.EndpointSlice{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:            "example-1",
+			Namespace:       "ns1",
+			ResourceVersion: "rv1",
+			Labels:          map[string]string{discovery.LabelServiceName: "svc1"},
+		},
+	}
+
+	epSlice1DifferentNS := epSlice1.DeepCopy()
+	epSlice1DifferentNS.Namespace = "ns2"
+
+	epSlice1DifferentService := epSlice1.DeepCopy()
+	epSlice1DifferentService.Labels[discovery.LabelServiceName] = "svc2"
+
+	epSlice1DifferentRV := epSlice1.DeepCopy()
+	epSlice1DifferentRV.ResourceVersion = "rv2"
+
+	testCases := map[string]struct {
+		updateParam *discovery.EndpointSlice
+		checksParam *discovery.EndpointSlice
+		expectHas   bool
+		expectStale bool
+	}{
+		"same slice": {
+			updateParam: epSlice1,
+			checksParam: epSlice1,
+			expectHas:   true,
+			expectStale: false,
+		},
+		"different namespace": {
+			updateParam: epSlice1,
+			checksParam: epSlice1DifferentNS,
+			expectHas:   false,
+			expectStale: true,
+		},
+		"different service": {
+			updateParam: epSlice1,
+			checksParam: epSlice1DifferentService,
+			expectHas:   false,
+			expectStale: true,
+		},
+		"different resource version": {
+			updateParam: epSlice1,
+			checksParam: epSlice1DifferentRV,
+			expectHas:   true,
+			expectStale: true,
+		},
+	}
+
+	for name, tc := range testCases {
+		t.Run(name, func(t *testing.T) {
+			esTracker := newEndpointSliceTracker()
+			esTracker.update(tc.updateParam)
+			if esTracker.has(tc.checksParam) != tc.expectHas {
+				t.Errorf("tc.tracker.has(%+v) == %t, expected %t", tc.checksParam, esTracker.has(tc.checksParam), tc.expectHas)
+			}
+			if esTracker.stale(tc.checksParam) != tc.expectStale {
+				t.Errorf("tc.tracker.stale(%+v) == %t, expected %t", tc.checksParam, esTracker.stale(tc.checksParam), tc.expectStale)
+			}
+		})
+	}
+}
+
+func TestEndpointSliceTrackerDelete(t *testing.T) {
+	epSlice1 := &discovery.EndpointSlice{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:            "example-1",
+			Namespace:       "ns1",
+			ResourceVersion: "rv1",
+			Labels:          map[string]string{discovery.LabelServiceName: "svc1"},
+		},
+	}
+
+	epSlice1DifferentNS := epSlice1.DeepCopy()
+	epSlice1DifferentNS.Namespace = "ns2"
+
+	epSlice1DifferentService := epSlice1.DeepCopy()
+	epSlice1DifferentService.Labels[discovery.LabelServiceName] = "svc2"
+
+	epSlice1DifferentRV := epSlice1.DeepCopy()
+	epSlice1DifferentRV.ResourceVersion = "rv2"
+
+	testCases := map[string]struct {
+		deleteParam *discovery.EndpointSlice
+		checksParam *discovery.EndpointSlice
+		expectHas   bool
+		expectStale bool
+	}{
+		"same slice": {
+			deleteParam: epSlice1,
+			checksParam: epSlice1,
+			expectHas:   false,
+			expectStale: true,
+		},
+		"different namespace": {
+			deleteParam: epSlice1DifferentNS,
+			checksParam: epSlice1DifferentNS,
+			expectHas:   false,
+			expectStale: true,
+		},
+		"different namespace, check original ep slice": {
+			deleteParam: epSlice1DifferentNS,
+			checksParam: epSlice1,
+			expectHas:   true,
+			expectStale: false,
+		},
+		"different service": {
+			deleteParam: epSlice1DifferentService,
+			checksParam: epSlice1DifferentService,
+			expectHas:   false,
+			expectStale: true,
+		},
+		"different service, check original ep slice": {
+			deleteParam: epSlice1DifferentService,
+			checksParam: epSlice1,
+			expectHas:   true,
+			expectStale: false,
+		},
+		"different resource version": {
+			deleteParam: epSlice1DifferentRV,
+			checksParam: epSlice1DifferentRV,
+			expectHas:   false,
+			expectStale: true,
+		},
+		"different resource version, check original ep slice": {
+			deleteParam: epSlice1DifferentRV,
+			checksParam: epSlice1,
+			expectHas:   false,
+			expectStale: true,
+		},
+	}
+
+	for name, tc := range testCases {
+		t.Run(name, func(t *testing.T) {
+			esTracker := newEndpointSliceTracker()
+			esTracker.update(epSlice1)
+
+			esTracker.delete(tc.deleteParam)
+			if esTracker.has(tc.checksParam) != tc.expectHas {
+				t.Errorf("esTracker.has(%+v) == %t, expected %t", tc.checksParam, esTracker.has(tc.checksParam), tc.expectHas)
+			}
+			if esTracker.stale(tc.checksParam) != tc.expectStale {
+				t.Errorf("esTracker.stale(%+v) == %t, expected %t", tc.checksParam, esTracker.stale(tc.checksParam), tc.expectStale)
+			}
+		})
+	}
+}