feat: Support XValidations (CEL) for CC variables (#916)

Updating to support latest features in Cluster API 1.8.

Author: jimmidyson

common/pkg/capi/clustertopology/variables/fromcrdyaml.go

@@ -5,6 +5,7 @@ package variables
 
 import (
 	"fmt"
+	"math"
 
 	apiextensionsv1 "k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1"
 	"k8s.io/apimachinery/pkg/runtime"
@@ -71,6 +72,39 @@ func ConvertAPIExtensionsToJSONSchemaProps(
 ) (*clusterv1.JSONSchemaProps, field.ErrorList) {
 	var allErrs field.ErrorList
 
+	// Check if minimum/maximum is a whole number that we can convert to int64 without loss of precision.
+	var maximumAsInt64Ptr, minimumAsInt64Ptr *int64
+	if schema.Maximum != nil {
+		maximumAsFloat64 := ptr.Deref(schema.Maximum, 0.0)
+		if math.Ceil(maximumAsFloat64) == maximumAsFloat64 {
+			maximumAsInt64Ptr = ptr.To(int64(maximumAsFloat64))
+		} else {
+			allErrs = append(
+				allErrs,
+				field.Invalid(
+					fldPath.Child("maximum"),
+					maximumAsFloat64,
+					"ClusterClass variables only support a whole number for maximum",
+				),
+			)
+		}
+	}
+	if schema.Minimum != nil {
+		minimumAsFloat64 := ptr.Deref(schema.Minimum, 0.0)
+		if math.Ceil(minimumAsFloat64) == minimumAsFloat64 {
+			minimumAsInt64Ptr = ptr.To(int64(minimumAsFloat64))
+		} else {
+			allErrs = append(
+				allErrs,
+				field.Invalid(
+					fldPath.Child("minimum"),
+					minimumAsFloat64,
+					"ClusterClass variables only support a whole number for minimum",
+				),
+			)
+		}
+	}
+
 	props := &clusterv1.JSONSchemaProps{
 		Type:                   schema.Type,
 		Required:               schema.Required,
@@ -81,20 +115,17 @@ func ConvertAPIExtensionsToJSONSchemaProps(
 		MaxLength:              schema.MaxLength,
 		MinLength:              schema.MinLength,
 		Pattern:                schema.Pattern,
+		Maximum:                maximumAsInt64Ptr,
+		Minimum:                minimumAsInt64Ptr,
 		ExclusiveMaximum:       schema.ExclusiveMaximum,
 		ExclusiveMinimum:       schema.ExclusiveMinimum,
 		XPreserveUnknownFields: ptr.Deref(schema.XPreserveUnknownFields, false),
 		Default:                schema.Default,
 		Enum:                   schema.Enum,
 		Example:                schema.Example,
-	}
-
-	if schema.Maximum != nil {
-		props.Maximum = ptr.To(int64(*schema.Maximum))
-	}
-
-	if schema.Minimum != nil {
-		props.Minimum = ptr.To(int64(*schema.Minimum))
+		Description:            schema.Description,
+		MaxProperties:          schema.MaxProperties,
+		MinProperties:          schema.MinProperties,
 	}
 
 	if schema.AdditionalProperties != nil && schema.AdditionalProperties.Schema != nil {
@@ -157,5 +188,22 @@ func ConvertAPIExtensionsToJSONSchemaProps(
 		}
 	}
 
+	if schema.XValidations != nil {
+		props.XValidations = make([]clusterv1.ValidationRule, 0, len(schema.XValidations))
+		for _, v := range schema.XValidations {
+			reason := ""
+			if v.Reason != nil {
+				reason = string(*v.Reason)
+			}
+			props.XValidations = append(props.XValidations, clusterv1.ValidationRule{
+				Rule:              v.Rule,
+				Message:           v.Message,
+				MessageExpression: v.MessageExpression,
+				Reason:            clusterv1.FieldValueErrorReason(reason),
+				FieldPath:         v.FieldPath,
+			})
+		}
+	}
+
 	return props, allErrs
 }