Validate clusterAutoscalerSpec

pkg/apis/kops/validation/validation.go

@@ -150,6 +150,10 @@ func validateClusterSpec(spec *kops.ClusterSpec, c *kops.Cluster, fieldPath *fie
 		allErrs = append(allErrs, validateNodeAuthorization(spec.NodeAuthorization, c, fieldPath.Child("nodeAuthorization"))...)
 	}
 
+	if spec.ClusterAutoscaler != nil {
+		allErrs = append(allErrs, validateClusterAutoscaler(c, spec.ClusterAutoscaler, fieldPath.Child("clusterAutoscaler"))...)
+	}
+
 	// IAM additionalPolicies
 	if spec.AdditionalPolicies != nil {
 		for k, v := range *spec.AdditionalPolicies {
@@ -1119,3 +1123,17 @@ func validateNodeLocalDNS(spec *kops.ClusterSpec, fldpath *field.Path) field.Err
 
 	return allErrs
 }
+
+func validateClusterAutoscaler(cluster *kops.Cluster, spec *kops.ClusterAutoscalerConfig, fldPath *field.Path) (allErrs field.ErrorList) {
+	if !cluster.IsKubernetesGTE("1.15") || cluster.IsKubernetesGTE("1.20") {
+		allErrs = append(allErrs, field.Forbidden(fldPath, "Cluster autoscaler requires kubernetesVersion between 1.11 and 1.19"))
+	}
+
+	allErrs = append(allErrs, IsValidValue(fldPath.Child("expander"), spec.Expander, []string{"least-waste", "random", "most-pods"})...)
+
+	if kops.CloudProviderID(cluster.Spec.CloudProvider) == kops.CloudProviderOpenstack {
+		allErrs = append(allErrs, field.Forbidden(fldPath, "Cluster autoscaler is not supported on OpenStack"))
+	}
+
+	return allErrs
+}