Ignore EndpointSlices that are already marked for deletion

Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>

pkg/controller/util/endpointslice/endpointslice_tracker.go

@@ -84,7 +84,7 @@ func (est *EndpointSliceTracker) ShouldSync(endpointSlice *discovery.EndpointSli
 // 1. One or more of the provided EndpointSlices have older generations than the
 //    corresponding tracked ones.
 // 2. The tracker is expecting one or more of the provided EndpointSlices to be
-//    deleted.
+//    deleted. (EndpointSlices that have already been marked for deletion are ignored here.)
 // 3. The tracker is tracking EndpointSlices that have not been provided.
 func (est *EndpointSliceTracker) StaleSlices(service *v1.Service, endpointSlices []*discovery.EndpointSlice) bool {
 	est.lock.Lock()
@@ -100,6 +100,9 @@ func (est *EndpointSliceTracker) StaleSlices(service *v1.Service, endpointSlices
 		providedSlices[endpointSlice.UID] = endpointSlice.Generation
 		g, ok := gfs[endpointSlice.UID]
 		if ok && (g == deletionExpected || g > endpointSlice.Generation) {
+			if endpointSlice.DeletionTimestamp != nil {
+				continue
+			}
 			return true
 		}
 	}

pkg/controller/util/endpointslice/endpointslice_tracker_test.go

@@ -124,6 +124,10 @@ func TestEndpointSliceTrackerStaleSlices(t *testing.T) {
 	epSlice1NewerGen := epSlice1.DeepCopy()
 	epSlice1NewerGen.Generation = 2
 
+	epTerminatingSlice := epSlice1.DeepCopy()
+	now := metav1.Now()
+	epTerminatingSlice.DeletionTimestamp = &now
+
 	testCases := []struct {
 		name         string
 		tracker      *EndpointSliceTracker
@@ -208,6 +212,18 @@ func TestEndpointSliceTrackerStaleSlices(t *testing.T) {
 		serviceParam: &v1.Service{ObjectMeta: metav1.ObjectMeta{Name: "svc1", Namespace: "ns1"}},
 		slicesParam:  []*discovery.EndpointSlice{},
 		expectNewer:  true,
+	}, {
+		name: "slice in params is has non nil deletion timestamp",
+		tracker: &EndpointSliceTracker{
+			generationsByService: map[types.NamespacedName]GenerationsBySlice{
+				{Name: "svc1", Namespace: "ns1"}: {
+					epSlice1.UID: epSlice1.Generation,
+				},
+			},
+		},
+		serviceParam: &v1.Service{ObjectMeta: metav1.ObjectMeta{Name: "svc1", Namespace: "ns1"}},
+		slicesParam:  []*discovery.EndpointSlice{epTerminatingSlice},
+		expectNewer:  false,
 	}}
 
 	for _, tc := range testCases {