make update false for immutable fields of persistentVolume

apis/cluster.cattle.io/v3/schema/schema.go

@@ -1,6 +1,9 @@
 package schema
 
 import (
+	"reflect"
+	"strings"
+
 	"github.com/rancher/norman/types"
 	m "github.com/rancher/norman/types/mapper"
 	"github.com/rancher/types/apis/cluster.cattle.io/v3"
@@ -78,7 +81,24 @@ func persistentVolumeTypes(schemas *types.Schemas) *types.Schemas {
 		}{}).
 		MustImport(&Version, v1.PersistentVolume{}, struct {
 			Description string `json:"description"`
-		}{})
+		}{}).
+		MustImportAndCustomize(&Version, v1.PersistentVolume{}, func(schema *types.Schema) {
+			schema.MustCustomizeField("volumeMode", func(field types.Field) types.Field {
+				field.Update = false
+				return field
+			})
+			// All fields of PersistentVolumeSource are immutable
+			val := reflect.ValueOf(v1.PersistentVolumeSource{})
+			for i := 0; i < val.Type().NumField(); i++ {
+				if tag, ok := val.Type().Field(i).Tag.Lookup("json"); ok {
+					name := strings.Split(tag, ",")[0]
+					schema.MustCustomizeField(name, func(field types.Field) types.Field {
+						field.Update = false
+						return field
+					})
+				}
+			}
+		})
 }
 
 func storageClassTypes(schemas *types.Schemas) *types.Schemas {