Do not allow empty topology key for pod affinities.

pkg/api/types.go

@@ -2026,9 +2026,7 @@ type PodAffinityTerm struct {
 	// the labelSelector in the specified namespaces, where co-located is defined as running on a node
 	// whose value of the label with key topologyKey matches that of any node on which any of the
 	// selected pods is running.
-	// For PreferredDuringScheduling pod anti-affinity, empty topologyKey is interpreted as "all topologies"
-	// ("all topologies" here means all the topologyKeys indicated by scheduler command-line argument --failure-domains);
-	// for affinity and for RequiredDuringScheduling pod anti-affinity, empty topologyKey is not allowed.
+	// Empty topologyKey is not allowed.
 	// +optional
 	TopologyKey string
 }

pkg/api/validation/validation.go

@@ -2429,7 +2429,7 @@ func ValidatePreferredSchedulingTerms(terms []api.PreferredSchedulingTerm, fldPa
 }
 
 // validatePodAffinityTerm tests that the specified podAffinityTerm fields have valid data
-func validatePodAffinityTerm(podAffinityTerm api.PodAffinityTerm, allowEmptyTopologyKey bool, fldPath *field.Path) field.ErrorList {
+func validatePodAffinityTerm(podAffinityTerm api.PodAffinityTerm, fldPath *field.Path) field.ErrorList {
 	allErrs := field.ErrorList{}
 
 	allErrs = append(allErrs, unversionedvalidation.ValidateLabelSelector(podAffinityTerm.LabelSelector, fldPath.Child("matchExpressions"))...)
@@ -2438,32 +2438,29 @@ func validatePodAffinityTerm(podAffinityTerm api.PodAffinityTerm, allowEmptyTopo
 			allErrs = append(allErrs, field.Invalid(fldPath.Child("namespace"), name, msg))
 		}
 	}
-	if !allowEmptyTopologyKey && len(podAffinityTerm.TopologyKey) == 0 {
-		allErrs = append(allErrs, field.Required(fldPath.Child("topologyKey"), "can only be empty for PreferredDuringScheduling pod anti affinity"))
+	if len(podAffinityTerm.TopologyKey) == 0 {
+		allErrs = append(allErrs, field.Required(fldPath.Child("topologyKey"), "can not be empty"))
 	}
-	if len(podAffinityTerm.TopologyKey) != 0 {
-		allErrs = append(allErrs, unversionedvalidation.ValidateLabelName(podAffinityTerm.TopologyKey, fldPath.Child("topologyKey"))...)
-	}
-	return allErrs
+	return append(allErrs, unversionedvalidation.ValidateLabelName(podAffinityTerm.TopologyKey, fldPath.Child("topologyKey"))...)
 }
 
 // validatePodAffinityTerms tests that the specified podAffinityTerms fields have valid data
-func validatePodAffinityTerms(podAffinityTerms []api.PodAffinityTerm, allowEmptyTopologyKey bool, fldPath *field.Path) field.ErrorList {
+func validatePodAffinityTerms(podAffinityTerms []api.PodAffinityTerm, fldPath *field.Path) field.ErrorList {
 	allErrs := field.ErrorList{}
 	for i, podAffinityTerm := range podAffinityTerms {
-		allErrs = append(allErrs, validatePodAffinityTerm(podAffinityTerm, allowEmptyTopologyKey, fldPath.Index(i))...)
+		allErrs = append(allErrs, validatePodAffinityTerm(podAffinityTerm, fldPath.Index(i))...)
 	}
 	return allErrs
 }
 
 // validateWeightedPodAffinityTerms tests that the specified weightedPodAffinityTerms fields have valid data
-func validateWeightedPodAffinityTerms(weightedPodAffinityTerms []api.WeightedPodAffinityTerm, allowEmptyTopologyKey bool, fldPath *field.Path) field.ErrorList {
+func validateWeightedPodAffinityTerms(weightedPodAffinityTerms []api.WeightedPodAffinityTerm, fldPath *field.Path) field.ErrorList {
 	allErrs := field.ErrorList{}
 	for j, weightedTerm := range weightedPodAffinityTerms {
 		if weightedTerm.Weight <= 0 || weightedTerm.Weight > 100 {
 			allErrs = append(allErrs, field.Invalid(fldPath.Index(j).Child("weight"), weightedTerm.Weight, "must be in the range 1-100"))
 		}
-		allErrs = append(allErrs, validatePodAffinityTerm(weightedTerm.PodAffinityTerm, allowEmptyTopologyKey, fldPath.Index(j).Child("podAffinityTerm"))...)
+		allErrs = append(allErrs, validatePodAffinityTerm(weightedTerm.PodAffinityTerm, fldPath.Index(j).Child("podAffinityTerm"))...)
 	}
 	return allErrs
 }
@@ -2477,13 +2474,11 @@ func validatePodAntiAffinity(podAntiAffinity *api.PodAntiAffinity, fldPath *fiel
 	//		fldPath.Child("requiredDuringSchedulingRequiredDuringExecution"))...)
 	//}
 	if podAntiAffinity.RequiredDuringSchedulingIgnoredDuringExecution != nil {
-		// empty topologyKey is not allowed for hard pod anti-affinity
-		allErrs = append(allErrs, validatePodAffinityTerms(podAntiAffinity.RequiredDuringSchedulingIgnoredDuringExecution, false,
+		allErrs = append(allErrs, validatePodAffinityTerms(podAntiAffinity.RequiredDuringSchedulingIgnoredDuringExecution,
 			fldPath.Child("requiredDuringSchedulingIgnoredDuringExecution"))...)
 	}
 	if podAntiAffinity.PreferredDuringSchedulingIgnoredDuringExecution != nil {
-		// empty topologyKey is allowed for soft pod anti-affinity
-		allErrs = append(allErrs, validateWeightedPodAffinityTerms(podAntiAffinity.PreferredDuringSchedulingIgnoredDuringExecution, true,
+		allErrs = append(allErrs, validateWeightedPodAffinityTerms(podAntiAffinity.PreferredDuringSchedulingIgnoredDuringExecution,
 			fldPath.Child("preferredDuringSchedulingIgnoredDuringExecution"))...)
 	}
 	return allErrs
@@ -2498,13 +2493,11 @@ func validatePodAffinity(podAffinity *api.PodAffinity, fldPath *field.Path) fiel
 	//		fldPath.Child("requiredDuringSchedulingRequiredDuringExecution"))...)
 	//}
 	if podAffinity.RequiredDuringSchedulingIgnoredDuringExecution != nil {
-		// empty topologyKey is not allowed for hard pod affinity
-		allErrs = append(allErrs, validatePodAffinityTerms(podAffinity.RequiredDuringSchedulingIgnoredDuringExecution, false,
+		allErrs = append(allErrs, validatePodAffinityTerms(podAffinity.RequiredDuringSchedulingIgnoredDuringExecution,
 			fldPath.Child("requiredDuringSchedulingIgnoredDuringExecution"))...)
 	}
 	if podAffinity.PreferredDuringSchedulingIgnoredDuringExecution != nil {
-		// empty topologyKey is not allowed for soft pod affinity
-		allErrs = append(allErrs, validateWeightedPodAffinityTerms(podAffinity.PreferredDuringSchedulingIgnoredDuringExecution, false,
+		allErrs = append(allErrs, validateWeightedPodAffinityTerms(podAffinity.PreferredDuringSchedulingIgnoredDuringExecution,
 			fldPath.Child("preferredDuringSchedulingIgnoredDuringExecution"))...)
 	}
 	return allErrs

pkg/api/validation/validation_test.go

@@ -4655,8 +4655,8 @@ func TestValidatePod(t *testing.T) {
 				}),
 			},
 		},
-		"invalid pod affinity, empty topologyKey is not allowed for hard pod affinity": {
-			expectedError: "can only be empty for PreferredDuringScheduling pod anti affinity",
+		"invalid hard pod affinity, empty topologyKey is not allowed for hard pod affinity": {
+			expectedError: "can not be empty",
 			spec: api.Pod{
 				ObjectMeta: metav1.ObjectMeta{
 					Name:      "123",
@@ -4682,8 +4682,8 @@ func TestValidatePod(t *testing.T) {
 				}),
 			},
 		},
-		"invalid pod anti-affinity, empty topologyKey is not allowed for hard pod anti-affinity": {
-			expectedError: "can only be empty for PreferredDuringScheduling pod anti affinity",
+		"invalid hard pod anti-affinity, empty topologyKey is not allowed for hard pod anti-affinity": {
+			expectedError: "can not be empty",
 			spec: api.Pod{
 				ObjectMeta: metav1.ObjectMeta{
 					Name:      "123",
@@ -4709,8 +4709,8 @@ func TestValidatePod(t *testing.T) {
 				}),
 			},
 		},
-		"invalid pod anti-affinity, empty topologyKey is not allowed for soft pod affinity": {
-			expectedError: "can only be empty for PreferredDuringScheduling pod anti affinity",
+		"invalid soft pod affinity, empty topologyKey is not allowed for soft pod affinity": {
+			expectedError: "can not be empty",
 			spec: api.Pod{
 				ObjectMeta: metav1.ObjectMeta{
 					Name:      "123",
@@ -4739,6 +4739,36 @@ func TestValidatePod(t *testing.T) {
 				}),
 			},
 		},
+		"invalid soft pod anti-affinity, empty topologyKey is not allowed for soft pod anti-affinity": {
+			expectedError: "can not be empty",
+			spec: api.Pod{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "123",
+					Namespace: "ns",
+				},
+				Spec: validPodSpec(&api.Affinity{
+					PodAntiAffinity: &api.PodAntiAffinity{
+						PreferredDuringSchedulingIgnoredDuringExecution: []api.WeightedPodAffinityTerm{
+							{
+								Weight: 10,
+								PodAffinityTerm: api.PodAffinityTerm{
+									LabelSelector: &metav1.LabelSelector{
+										MatchExpressions: []metav1.LabelSelectorRequirement{
+											{
+												Key:      "key2",
+												Operator: metav1.LabelSelectorOpNotIn,
+												Values:   []string{"value1", "value2"},
+											},
+										},
+									},
+									Namespaces: []string{"ns"},
+								},
+							},
+						},
+					},
+				}),
+			},
+		},
 		"invalid toleration key": {
 			expectedError: "spec.tolerations[0].key",
 			spec: api.Pod{

plugin/pkg/scheduler/algorithm/priorities/util/topologies.go

@@ -75,7 +75,6 @@ type Topologies struct {
 }
 
 // NodesHaveSameTopologyKey checks if nodeA and nodeB have same label value with given topologyKey as label key.
-// If the topologyKey is empty, check if the two nodes have any of the default topologyKeys, and have same corresponding label value.
 func (tps *Topologies) NodesHaveSameTopologyKey(nodeA, nodeB *v1.Node, topologyKey string) bool {
 	return NodesHaveSameTopologyKey(nodeA, nodeB, topologyKey)
 }