fix: include node events with null involvedObject.uid in describe output

kubectl describe node omits events where involvedObject.uid is
unset/null. This happens with kubelet-emitted node status events
on some clusters (e.g. EKS).

NodeDescriber.Describe() searched for events using two UIDs:
1. The node's real UID (for controller events)
2. The node name as UID (for kubelet events using name workaround)

Neither matched events where involvedObject.uid is null/empty.

Add a third search with empty UID (matching by kind+name only)
and deduplicate the merged results to avoid showing duplicates.

Ref: kubernetes/kubectl/issues/1838

Signed-off-by: vigneshakaviki <kumarvignesh295@gmail.com>

pkg/describe/describe.go

@@ -3467,14 +3467,35 @@ func (d *NodeDescriber) Describe(namespace, name string, describerSettings Descr
 			// there are two UIDs for host events:
 			// controller use node.uid
 			// kubelet use node.name
+			// some kubelet events have involvedObject.uid unset (null)
 			// TODO: Uniform use of UID
 			events, _ = searchEvents(d.CoreV1(), ref, describerSettings.ChunkSize)
 
 			ref.UID = types.UID(ref.Name)
 			eventsInvName, _ := searchEvents(d.CoreV1(), ref, describerSettings.ChunkSize)
 
-			// Merge the results of two queries
-			events.Items = append(events.Items, eventsInvName.Items...)
+			// Search for events with no UID set (involvedObject.uid is null),
+			// which can happen with kubelet-emitted node events.
+			ref.UID = ""
+			eventsNoUID, _ := searchEvents(d.CoreV1(), ref, describerSettings.ChunkSize)
+
+			// Merge and deduplicate the results of the three queries
+			seen := make(map[types.UID]bool, len(events.Items))
+			for _, e := range events.Items {
+				seen[e.UID] = true
+			}
+			for _, e := range eventsInvName.Items {
+				if !seen[e.UID] {
+					events.Items = append(events.Items, e)
+					seen[e.UID] = true
+				}
+			}
+			for _, e := range eventsNoUID.Items {
+				if !seen[e.UID] {
+					events.Items = append(events.Items, e)
+					seen[e.UID] = true
+				}
+			}
 		}
 	}
 

pkg/describe/describe_test.go

@@ -6447,6 +6447,79 @@ func TestDescribeNode(t *testing.T) {
 	}
 }
 
+func TestDescribeNodeEventsWithNullUID(t *testing.T) {
+	node := &corev1.Node{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "test-node",
+			UID:  "real-node-uid",
+		},
+	}
+	fake := fake.NewClientset(
+		node,
+		&coordinationv1.Lease{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      "test-node",
+				Namespace: corev1.NamespaceNodeLease,
+			},
+		},
+		&corev1.EventList{
+			Items: []corev1.Event{
+				{
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "event-with-uid",
+						Namespace: "default",
+						UID:       "evt-1",
+					},
+					InvolvedObject: corev1.ObjectReference{
+						Kind: "Node",
+						Name: "test-node",
+						UID:  "test-node",
+					},
+					Message:        "Node test-node status is now: NodeHasSufficientMemory",
+					FirstTimestamp: metav1.NewTime(time.Date(2024, time.January, 15, 0, 0, 0, 0, time.UTC)),
+					LastTimestamp:  metav1.NewTime(time.Date(2024, time.January, 15, 0, 0, 0, 0, time.UTC)),
+					Count:          1,
+					Type:           corev1.EventTypeNormal,
+				},
+				{
+					ObjectMeta: metav1.ObjectMeta{
+						Name:      "event-null-uid",
+						Namespace: "default",
+						UID:       "evt-2",
+					},
+					InvolvedObject: corev1.ObjectReference{
+						Kind: "Node",
+						Name: "test-node",
+						// UID intentionally omitted (empty/null) —
+						// kubelet-emitted events on some clusters
+					},
+					Message:        "Node test-node status is now: NodeHasInsufficientMemory",
+					FirstTimestamp: metav1.NewTime(time.Date(2024, time.January, 15, 0, 0, 0, 0, time.UTC)),
+					LastTimestamp:  metav1.NewTime(time.Date(2024, time.January, 15, 0, 0, 0, 0, time.UTC)),
+					Count:          1,
+					Type:           corev1.EventTypeWarning,
+				},
+			},
+		},
+	)
+	c := &describeClient{T: t, Namespace: "", Interface: fake}
+	d := NodeDescriber{c}
+	out, err := d.Describe("", "test-node", DescriberSettings{ShowEvents: true})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+
+	// Event with UID should always appear
+	if !strings.Contains(out, "NodeHasSufficientMemory") {
+		t.Errorf("expected event with UID to appear in output, got:\n%s", out)
+	}
+
+	// Event with null/empty UID should also appear
+	if !strings.Contains(out, "NodeHasInsufficientMemory") {
+		t.Errorf("expected event with null UID to appear in output, got:\n%s", out)
+	}
+}
+
 func TestDescribeNodeWithSidecar(t *testing.T) {
 	holderIdentity := "holder"
 	nodeCapacity := mergeResourceLists(