fix: surface unknown eviction conditions in draincluster

tools/fleet/cmd/draincluster/draincluster.go

@@ -186,19 +186,19 @@ func (o *drainOptions) drain(ctx context.Context) (bool, error) {
 			return false, fmt.Errorf("failed to wait for eviction %s for CRP %s targeting member cluster %s to reach terminal state: %w", evictionName, crpName, o.clusterName, err)
 		}
 
-		// TODO: add safeguards to check if eviction conditions are set to unknown.
-		validCondition := eviction.GetCondition(string(placementv1beta1.PlacementEvictionConditionTypeValid))
-		if validCondition != nil && validCondition.Status == metav1.ConditionFalse {
-			// check to see if CRP is missing or CRP is being deleted or CRB is missing.
-			if validCondition.Reason == condition.EvictionInvalidMissingCRPMessage ||
-				validCondition.Reason == condition.EvictionInvalidDeletingCRPMessage ||
-				validCondition.Reason == condition.EvictionInvalidMissingCRBMessage {
-				log.Printf("eviction %s is invalid with reason %s for CRP %s targeting member cluster %s, but drain will succeed", evictionName, validCondition.Reason, crpName, o.clusterName)
-				continue
-			}
-		}
-		executedCondition := eviction.GetCondition(string(placementv1beta1.PlacementEvictionConditionTypeExecuted))
-		if executedCondition == nil || executedCondition.Status == metav1.ConditionFalse {
+		// Classify the terminal eviction. A missing or Unknown Valid/Executed
+		// condition is never treated as success, so an uncertain eviction is not
+		// reported as a completed drain (see evaluateEviction).
+		switch evaluateEviction(&eviction) {
+		case evictionResultInvalidButDrained:
+			validCondition := eviction.GetCondition(string(placementv1beta1.PlacementEvictionConditionTypeValid))
+			log.Printf("eviction %s is invalid with reason %s for CRP %s targeting member cluster %s, but drain will succeed", evictionName, validCondition.Reason, crpName, o.clusterName)
+			continue
+		case evictionResultIndeterminate:
+			isDrainSuccessful = false
+			log.Printf("eviction %s has a missing or unknown Valid or Executed condition for CRP %s targeting member cluster %s; cannot confirm drain", evictionName, crpName, o.clusterName)
+			continue
+		case evictionResultNotExecuted:
 			isDrainSuccessful = false
 			log.Printf("eviction %s was not executed successfully for CRP %s targeting member cluster %s", evictionName, crpName, o.clusterName)
 			continue
@@ -218,6 +218,48 @@ func (o *drainOptions) drain(ctx context.Context) (bool, error) {
 	return isDrainSuccessful, nil
 }
 
+// evictionResult classifies the terminal state of a ClusterResourcePlacementEviction
+// based on its Valid and Executed conditions.
+type evictionResult int
+
+const (
+	// evictionResultIndeterminate means the eviction's Valid or Executed condition
+	// is missing or Unknown, so the drain cannot be confirmed.
+	evictionResultIndeterminate evictionResult = iota
+	// evictionResultInvalidButDrained means the eviction is invalid for a reason
+	// that still leaves the cluster drained (missing/deleting CRP or missing CRB).
+	evictionResultInvalidButDrained
+	// evictionResultNotExecuted means the eviction did not execute.
+	evictionResultNotExecuted
+	// evictionResultExecuted means the eviction executed successfully.
+	evictionResultExecuted
+)
+
+// evaluateEviction inspects a terminal eviction's Valid and Executed conditions and
+// classifies the outcome. A missing or Unknown condition is never treated as success.
+func evaluateEviction(eviction *placementv1beta1.ClusterResourcePlacementEviction) evictionResult {
+	validCondition := eviction.GetCondition(string(placementv1beta1.PlacementEvictionConditionTypeValid))
+	if validCondition == nil || validCondition.Status == metav1.ConditionUnknown {
+		return evictionResultIndeterminate
+	}
+	// An invalid eviction whose reason is a missing/deleting CRP or a missing CRB
+	// still means the cluster is drained.
+	if validCondition.Status == metav1.ConditionFalse &&
+		(validCondition.Reason == condition.EvictionInvalidMissingCRPMessage ||
+			validCondition.Reason == condition.EvictionInvalidDeletingCRPMessage ||
+			validCondition.Reason == condition.EvictionInvalidMissingCRBMessage) {
+		return evictionResultInvalidButDrained
+	}
+	executedCondition := eviction.GetCondition(string(placementv1beta1.PlacementEvictionConditionTypeExecuted))
+	if executedCondition == nil || executedCondition.Status == metav1.ConditionUnknown {
+		return evictionResultIndeterminate
+	}
+	if executedCondition.Status == metav1.ConditionFalse {
+		return evictionResultNotExecuted
+	}
+	return evictionResultExecuted
+}
+
 func (o *drainOptions) cordon(ctx context.Context) error {
 	// add taint to member cluster to ensure resources aren't scheduled on it.
 	return retry.RetryOnConflict(retry.DefaultRetry, func() error {

tools/fleet/cmd/draincluster/draincluster_test.go

@@ -32,6 +32,7 @@ import (
 
 	clusterv1beta1 "github.com/kubefleet-dev/kubefleet/apis/cluster/v1beta1"
 	placementv1beta1 "github.com/kubefleet-dev/kubefleet/apis/placement/v1beta1"
+	"github.com/kubefleet-dev/kubefleet/pkg/utils/condition"
 	toolsutils "github.com/kubefleet-dev/kubefleet/tools/utils"
 )
 
@@ -510,3 +511,105 @@ func serviceScheme(t *testing.T) *runtime.Scheme {
 	}
 	return scheme
 }
+
+func TestEvaluateEviction(t *testing.T) {
+	validType := string(placementv1beta1.PlacementEvictionConditionTypeValid)
+	executedType := string(placementv1beta1.PlacementEvictionConditionTypeExecuted)
+
+	tests := []struct {
+		name       string
+		conditions []metav1.Condition
+		want       evictionResult
+	}{
+		{
+			name: "valid true, executed true",
+			conditions: []metav1.Condition{
+				{Type: validType, Status: metav1.ConditionTrue, Reason: "Valid"},
+				{Type: executedType, Status: metav1.ConditionTrue, Reason: "Executed"},
+			},
+			want: evictionResultExecuted,
+		},
+		{
+			name: "valid true, executed false",
+			conditions: []metav1.Condition{
+				{Type: validType, Status: metav1.ConditionTrue, Reason: "Valid"},
+				{Type: executedType, Status: metav1.ConditionFalse, Reason: "NotExecuted"},
+			},
+			want: evictionResultNotExecuted,
+		},
+		{
+			name: "valid true, executed unknown",
+			conditions: []metav1.Condition{
+				{Type: validType, Status: metav1.ConditionTrue, Reason: "Valid"},
+				{Type: executedType, Status: metav1.ConditionUnknown, Reason: "Unknown"},
+			},
+			want: evictionResultIndeterminate,
+		},
+		{
+			name: "valid true, executed missing",
+			conditions: []metav1.Condition{
+				{Type: validType, Status: metav1.ConditionTrue, Reason: "Valid"},
+			},
+			want: evictionResultIndeterminate,
+		},
+		{
+			name: "valid unknown",
+			conditions: []metav1.Condition{
+				{Type: validType, Status: metav1.ConditionUnknown, Reason: "Unknown"},
+			},
+			want: evictionResultIndeterminate,
+		},
+		{
+			name:       "valid missing",
+			conditions: nil,
+			want:       evictionResultIndeterminate,
+		},
+		{
+			name: "valid false, reason missing CRP",
+			conditions: []metav1.Condition{
+				{Type: validType, Status: metav1.ConditionFalse, Reason: condition.EvictionInvalidMissingCRPMessage},
+			},
+			want: evictionResultInvalidButDrained,
+		},
+		{
+			name: "valid false, reason deleting CRP",
+			conditions: []metav1.Condition{
+				{Type: validType, Status: metav1.ConditionFalse, Reason: condition.EvictionInvalidDeletingCRPMessage},
+			},
+			want: evictionResultInvalidButDrained,
+		},
+		{
+			name: "valid false, reason missing CRB",
+			conditions: []metav1.Condition{
+				{Type: validType, Status: metav1.ConditionFalse, Reason: condition.EvictionInvalidMissingCRBMessage},
+			},
+			want: evictionResultInvalidButDrained,
+		},
+		{
+			name: "valid false with unrecognized reason, executed true",
+			conditions: []metav1.Condition{
+				{Type: validType, Status: metav1.ConditionFalse, Reason: "SomeOtherReason"},
+				{Type: executedType, Status: metav1.ConditionTrue, Reason: "Executed"},
+			},
+			want: evictionResultExecuted,
+		},
+		{
+			name: "valid false with unrecognized reason, executed unknown",
+			conditions: []metav1.Condition{
+				{Type: validType, Status: metav1.ConditionFalse, Reason: "SomeOtherReason"},
+				{Type: executedType, Status: metav1.ConditionUnknown, Reason: "Unknown"},
+			},
+			want: evictionResultIndeterminate,
+		},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			eviction := &placementv1beta1.ClusterResourcePlacementEviction{}
+			eviction.SetConditions(tc.conditions...)
+			if got := evaluateEviction(eviction); got != tc.want {
+				t.Errorf("evaluateEviction() = %v, want %v", got, tc.want)
+			}
+		})
+	}
+}