last-applied-config annotation no longer mirrored to endpoint slices

Handles incorrect mirroring of endpoint annotations to created endpoint
slices, specifically the last-applied-config. Also updates tests
and adds test cases for the same

pkg/controller/endpointslicemirroring/reconciler.go

@@ -197,8 +197,8 @@ func (r *reconciler) reconcileByPortMapping(
 		// if >0 existing slices, mark all but 1 for deletion.
 		slices.toDelete = existingSlices[1:]
 
-		// generated slices must mirror all endpoints annotations but EndpointsLastChangeTriggerTime
+		// generated slices must mirror all endpoints annotations but EndpointsLastChangeTriggerTime and LastAppliedConfigAnnotation
-		compareAnnotations := cloneAndRemoveKeys(endpoints.Annotations, corev1.EndpointsLastChangeTriggerTime)
+		compareAnnotations := cloneAndRemoveKeys(endpoints.Annotations, corev1.EndpointsLastChangeTriggerTime, corev1.LastAppliedConfigAnnotation)
 		compareLabels := cloneAndRemoveKeys(existingSlices[0].Labels, discovery.LabelManagedBy, discovery.LabelServiceName)
 		// Return early if first slice matches desired endpoints, labels and annotations
 		totals = totalChanges(existingSlices[0], desiredSet)

pkg/controller/endpointslicemirroring/reconciler_test.go

@@ -44,6 +44,7 @@ func TestReconcile(t *testing.T) {
 		testName                 string
 		subsets                  []corev1.EndpointSubset
 		epLabels                 map[string]string
+		epAnnotations            map[string]string
 		endpointsDeletionPending bool
 		maxEndpointsPerSubset    int32
 		existingEndpointSlices   []*discovery.EndpointSlice
@@ -791,6 +792,118 @@ func TestReconcile(t *testing.T) {
 		expectedClientActions:  2,
 		maxEndpointsPerSubset:  2,
 		expectedMetrics:        &expectedMetrics{desiredSlices: 2, actualSlices: 2, desiredEndpoints: 4, addedPerSync: 4, updatedPerSync: 0, removedPerSync: 0, skippedPerSync: 1, numCreated: 2, numUpdated: 0},
+	}, {
+		testName: "The last-applied-configuration annotation should not get mirrored to created or updated endpoint slices",
+		epAnnotations: map[string]string{
+			corev1.LastAppliedConfigAnnotation: "{\"apiVersion\":\"v1\",\"kind\":\"Endpoints\",\"subsets\":[]}",
+		},
+		subsets: []corev1.EndpointSubset{{
+			Ports: []corev1.EndpointPort{{
+				Name:     "http",
+				Port:     80,
+				Protocol: corev1.ProtocolTCP,
+			}},
+			Addresses: []corev1.EndpointAddress{{
+				IP:       "10.0.0.1",
+				Hostname: "pod-1",
+			}},
+		}},
+		existingEndpointSlices: []*discovery.EndpointSlice{},
+		expectedNumSlices:      1,
+		expectedClientActions:  1,
+		expectedMetrics:        &expectedMetrics{addedPerSync: 1, numCreated: 1, desiredEndpoints: 1, desiredSlices: 1, actualSlices: 1},
+	}, {
+		testName: "The last-applied-configuration annotation shouldn't get added to created endpoint slices",
+		subsets: []corev1.EndpointSubset{{
+			Ports: []corev1.EndpointPort{{
+				Name:     "http",
+				Port:     80,
+				Protocol: corev1.ProtocolTCP,
+			}},
+			Addresses: []corev1.EndpointAddress{{
+				IP:       "10.0.0.1",
+				Hostname: "pod-1",
+			}},
+		}},
+		existingEndpointSlices: []*discovery.EndpointSlice{},
+		expectedNumSlices:      1,
+		expectedClientActions:  1,
+		expectedMetrics:        &expectedMetrics{addedPerSync: 1, numCreated: 1, desiredEndpoints: 1, desiredSlices: 1, actualSlices: 1},
+	}, {
+		testName: "The last-applied-configuration shouldn't get mirrored to endpoint slices when it's value is empty",
+		epAnnotations: map[string]string{
+			corev1.LastAppliedConfigAnnotation: "",
+		},
+		subsets: []corev1.EndpointSubset{{
+			Ports: []corev1.EndpointPort{{
+				Name:     "http",
+				Port:     80,
+				Protocol: corev1.ProtocolTCP,
+			}},
+			Addresses: []corev1.EndpointAddress{{
+				IP:       "10.0.0.1",
+				Hostname: "pod-1",
+			}},
+		}},
+		existingEndpointSlices: []*discovery.EndpointSlice{},
+		expectedNumSlices:      1,
+		expectedClientActions:  1,
+		expectedMetrics:        &expectedMetrics{addedPerSync: 1, numCreated: 1, desiredEndpoints: 1, desiredSlices: 1, actualSlices: 1},
+	}, {
+		testName: "Annotations other than last-applied-configuration should get correctly mirrored",
+		epAnnotations: map[string]string{
+			corev1.LastAppliedConfigAnnotation: "{\"apiVersion\":\"v1\",\"kind\":\"Endpoints\",\"subsets\":[]}",
+			"foo":                              "bar",
+		},
+		subsets: []corev1.EndpointSubset{{
+			Ports: []corev1.EndpointPort{{
+				Name:     "http",
+				Port:     80,
+				Protocol: corev1.ProtocolTCP,
+			}},
+			Addresses: []corev1.EndpointAddress{{
+				IP:       "10.0.0.1",
+				Hostname: "pod-1",
+			}},
+		}},
+		existingEndpointSlices: []*discovery.EndpointSlice{},
+		expectedNumSlices:      1,
+		expectedClientActions:  1,
+		expectedMetrics:        &expectedMetrics{addedPerSync: 1, numCreated: 1, desiredEndpoints: 1, desiredSlices: 1, actualSlices: 1},
+	}, {
+		testName: "Annotation mirroring should remove the last-applied-configuration annotation from existing endpoint slices",
+		subsets: []corev1.EndpointSubset{{
+			Ports: []corev1.EndpointPort{{
+				Name:     "http",
+				Port:     80,
+				Protocol: corev1.ProtocolTCP,
+			}},
+			Addresses: []corev1.EndpointAddress{{
+				IP:       "10.0.0.1",
+				Hostname: "pod-1",
+			}},
+		}},
+		existingEndpointSlices: []*discovery.EndpointSlice{{
+			ObjectMeta: metav1.ObjectMeta{
+				Name: "test-ep-1",
+				Annotations: map[string]string{
+					corev1.LastAppliedConfigAnnotation: "{\"apiVersion\":\"v1\",\"kind\":\"Endpoints\",\"subsets\":[]}",
+				},
+			},
+			AddressType: discovery.AddressTypeIPv4,
+			Ports: []discovery.EndpointPort{{
+				Name:     utilpointer.StringPtr("http"),
+				Port:     utilpointer.Int32Ptr(80),
+				Protocol: &protoTCP,
+			}},
+			Endpoints: []discovery.Endpoint{{
+				Addresses:  []string{"10.0.0.1"},
+				Hostname:   utilpointer.StringPtr("pod-1"),
+				Conditions: discovery.EndpointConditions{Ready: utilpointer.BoolPtr(true)},
+			}},
+		}},
+		expectedNumSlices:     1,
+		expectedClientActions: 1,
 	}}
 
 	for _, tc := range testCases {
@@ -799,7 +912,7 @@ func TestReconcile(t *testing.T) {
 			setupMetrics()
 			namespace := "test"
 			endpoints := corev1.Endpoints{
-				ObjectMeta: metav1.ObjectMeta{Name: "test-ep", Namespace: namespace, Labels: tc.epLabels},
+				ObjectMeta: metav1.ObjectMeta{Name: "test-ep", Namespace: namespace, Labels: tc.epLabels, Annotations: tc.epAnnotations},
 				Subsets:    tc.subsets,
 			}
 
@@ -880,6 +993,25 @@ func expectEndpointSlices(t *testing.T, num, maxEndpointsPerSubset int, endpoint
 		if serviceNameVal != endpoints.Name {
 			t.Errorf("Expected EndpointSlice to have %s label set to %s, got %s", discovery.LabelServiceName, endpoints.Name, serviceNameVal)
 		}
+
+		_, ok = epSlice.Annotations[corev1.LastAppliedConfigAnnotation]
+		if ok {
+			t.Errorf("Expected LastAppliedConfigAnnotation to be unset, got %s", epSlice.Annotations[corev1.LastAppliedConfigAnnotation])
+		}
+
+		_, ok = epSlice.Annotations[corev1.EndpointsLastChangeTriggerTime]
+		if ok {
+			t.Errorf("Expected EndpointsLastChangeTriggerTime to be unset, got %s", epSlice.Annotations[corev1.EndpointsLastChangeTriggerTime])
+		}
+
+		for annotation, val := range endpoints.Annotations {
+			if annotation == corev1.EndpointsLastChangeTriggerTime || annotation == corev1.LastAppliedConfigAnnotation {
+				continue
+			}
+			if epSlice.Annotations[annotation] != val {
+				t.Errorf("Expected endpoint annotation %s to be mirrored correctly, got %s", annotation, epSlice.Annotations[annotation])
+			}
+		}
 	}
 
 	for _, epSubset := range endpoints.Subsets {

pkg/controller/endpointslicemirroring/utils.go

@@ -87,9 +87,9 @@ func newEndpointSlice(endpoints *corev1.Endpoints, ports []discovery.EndpointPor
 	epSlice.Labels[discovery.LabelServiceName] = endpoints.Name
 	epSlice.Labels[discovery.LabelManagedBy] = controllerName
 
-	// clone all annotations but EndpointsLastChangeTriggerTime
+	// clone all annotations but EndpointsLastChangeTriggerTime and LastAppliedConfigAnnotation
 	for annotation, val := range endpoints.Annotations {
-		if annotation == corev1.EndpointsLastChangeTriggerTime {
+		if annotation == corev1.EndpointsLastChangeTriggerTime || annotation == corev1.LastAppliedConfigAnnotation {
 			continue
 		}
 		epSlice.Annotations[annotation] = val