Ensure NillableDuration can round-trip with unstructured

Author: adammw

pkg/apis/v1/duration.go

@@ -17,6 +17,7 @@ limitations under the License.
 package v1
 
 import (
+	"encoding/base64"
 	"encoding/json"
 	"fmt"
 	"slices"
@@ -52,6 +53,17 @@ func (d *NillableDuration) UnmarshalJSON(b []byte) error {
 	if err != nil {
 		return err
 	}
+
+	// check for base64 encoded string, can happen from unstructuredConverter marshalling []byte
+	base64Decoded, err := base64.StdEncoding.DecodeString(str)
+	if err == nil && base64Decoded[0] == byte('"') {
+		b = base64Decoded
+		err = json.Unmarshal(base64Decoded, &str)
+		if err != nil {
+			return err
+		}
+	} // otherwise, it is not base64 encoded
+
 	if str == Never {
 		return nil
 	}

pkg/apis/v1/nodepool_validation_cel_test.go

@@ -72,6 +72,13 @@ var _ = Describe("CEL/Validation", func() {
 			nodePool.Spec.Template.Spec.ExpireAfter = MustParseNillableDuration("Never")
 			Expect(env.Client.Create(ctx, nodePool)).To(Succeed())
 		})
+		It("should support round trip to/from unstructured", func() {
+			nodePool.Spec.Template.Spec.ExpireAfter = MustParseNillableDuration("30s")
+			u := lo.Must(runtime.DefaultUnstructuredConverter.ToUnstructured(nodePool))
+			nodePool2 := &NodePool{}
+			lo.Must0(runtime.DefaultUnstructuredConverter.FromUnstructured(u, nodePool2))
+			Expect(nodePool2).To(Equal(nodePool))
+		})
 		DescribeTable("should succeed on a valid expireAfter", func(value string) {
 			u := lo.Must(runtime.DefaultUnstructuredConverter.ToUnstructured(nodePool))
 			lo.Must0(unstructured.SetNestedField(u, value, "spec", "template", "spec", "expireAfter"))