fix: missing immutable setup under type_def (#649)

This PR fixes an issue where the `is_immutable` configuration was not being applied to nested fields (e.g. `HealthCheckConfig.Type`). 

Verified using `route53-controller`. The generator now correctly applies validation markers to immutable nested fields in `HealthCheckConfig`, resulting in the correct `x-kubernetes-validations` in the output CRD.

```diff
diff --git a/apis/v1alpha1/types.go b/apis/v1alpha1/types.go
index afc17d0..e25f221 100644
--- a/apis/v1alpha1/types.go
+++ b/apis/v1alpha1/types.go
@@ -148,14 +148,18 @@ type HealthCheckConfig struct {
 	IPAddress                    *string          `json:"ipAddress,omitempty"`
 	InsufficientDataHealthStatus *string          `json:"insufficientDataHealthStatus,omitempty"`
 	Inverted                     *bool            `json:"inverted,omitempty"`
-	MeasureLatency               *bool            `json:"measureLatency,omitempty"`
-	Port                         *int64           `json:"port,omitempty"`
-	Regions                      []*string        `json:"regions,omitempty"`
-	RequestInterval              *int64           `json:"requestInterval,omitempty"`
-	ResourcePath                 *string          `json:"resourcePath,omitempty"`
-	RoutingControlARN            *string          `json:"routingControlARN,omitempty"`
-	SearchString                 *string          `json:"searchString,omitempty"`
-	Type                         *string          `json:"type,omitempty"`
+	// +kubebuilder:validation:XValidation:rule="self == oldSelf",message="Value is immutable once set"
+	MeasureLatency *bool     `json:"measureLatency,omitempty"`
+	Port           *int64    `json:"port,omitempty"`
+	Regions        []*string `json:"regions,omitempty"`
+	// +kubebuilder:validation:XValidation:rule="self == oldSelf",message="Value is immutable once set"
+	RequestInterval *int64  `json:"requestInterval,omitempty"`
+	ResourcePath    *string `json:"resourcePath,omitempty"`
+	// +kubebuilder:validation:XValidation:rule="self == oldSelf",message="Value is immutable once set"
+	RoutingControlARN *string `json:"routingControlARN,omitempty"`
+	SearchString      *string `json:"searchString,omitempty"`
+	// +kubebuilder:validation:XValidation:rule="self == oldSelf",message="Value is immutable once set"
+	Type *string `json:"type,omitempty"`
 }
 
 // A complex type that contains the last failure reason as reported by one Amazon
diff --git a/config/crd/bases/route53.services.k8s.aws_healthchecks.yaml b/config/crd/bases/route53.services.k8s.aws_healthchecks.yaml
index ea5e040..d55c176 100644
--- a/config/crd/bases/route53.services.k8s.aws_healthchecks.yaml
+++ b/config/crd/bases/route53.services.k8s.aws_healthchecks.yaml
@@ -82,6 +82,9 @@ spec:
                     type: string
                   measureLatency:
                     type: boolean
+                    x-kubernetes-validations:
+                    - message: Value is immutable once set
+                      rule: self == oldSelf
                   port:
                     format: int64
                     type: integer
@@ -92,14 +95,23 @@ spec:
                   requestInterval:
                     format: int64
                     type: integer
+                    x-kubernetes-validations:
+                    - message: Value is immutable once set
+                      rule: self == oldSelf
                   resourcePath:
                     type: string
                   routingControlARN:
                     type: string
+                    x-kubernetes-validations:
+                    - message: Value is immutable once set
+                      rule: self == oldSelf
                   searchString:
                     type: string
                   type:
                     type: string
+                    x-kubernetes-validations:
+                    - message: Value is immutable once set
+                      rule: self == oldSelf
                 type: object
               tags:
                 description: |-

```

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

Author: justin0u0

pkg/model/attr.go

@@ -21,10 +21,11 @@ import (
 )
 
 type Attr struct {
-	Names  names.Names
-	GoType string
-	Shape  *awssdkmodel.Shape
-	GoTag  string
+	Names       names.Names
+	GoType      string
+	Shape       *awssdkmodel.Shape
+	GoTag       string
+	IsImmutable bool
 }
 
 func NewAttr(

pkg/model/model.go

@@ -541,6 +541,9 @@ func (m *Model) processNestedFieldTypeDefs(
 			if field.FieldConfig.GoTag != nil {
 				setTypeDefAttributeGoTag(crd, fieldPath, field, tdefs)
 			}
+			if field.IsImmutable() {
+				setTypeDefAttributeImmutable(crd, fieldPath, tdefs)
+			}
 		}
 	}
 }
@@ -674,6 +677,15 @@ func setTypeDefAttributeGoTag(crd *CRD, fieldPath string, f *Field, tdefs []*Typ
 	}
 }
 
+// setTypeDefAttributeImmutable sets the IsImmutable flag for the corresponding
+// attribute represented by fieldPath of nested field.
+func setTypeDefAttributeImmutable(crd *CRD, fieldPath string, tdefs []*TypeDef) {
+	_, fieldAttr := getAttributeFromPath(crd, fieldPath, tdefs)
+	if fieldAttr != nil {
+		fieldAttr.IsImmutable = true
+	}
+}
+
 // updateTypeDefAttributeWithReference adds a new AWSResourceReference attribute
 // for the corresponding attribute represented by fieldPath of nested field
 func updateTypeDefAttributeWithReference(crd *CRD, fieldPath string, tdefs []*TypeDef) {

templates/apis/type_def.go.tpl

@@ -7,6 +7,9 @@ type {{ .Names.Camel }} struct {
 	{{- if $attr.Shape.Documentation }}
 	{{ $attr.Shape.Documentation }}
 	{{- end }}
+	{{- if $attr.IsImmutable }}
+	// +kubebuilder:validation:XValidation:rule="self == oldSelf",message="Value is immutable once set"
+	{{- end }}
 	{{ $attr.Names.Camel }} {{ $attr.GoType }} {{ $attr.GetGoTag }}
 {{- end }}
 }