Plug deduced type in

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/fieldmanager/fieldmanager.go

@@ -61,6 +61,22 @@ func NewFieldManager(models openapiproto.Models, objectConverter runtime.ObjectC
 	}, nil
 }
 
+// NewCRDFieldManager creates a new FieldManager specifically for
+// CRDs. This doesn't use openapi models (and it doesn't support the
+// validation field right now).
+func NewCRDFieldManager(objectConverter runtime.ObjectConvertor, objectDefaulter runtime.ObjectDefaulter, gv schema.GroupVersion, hub schema.GroupVersion) *FieldManager {
+	return &FieldManager{
+		typeConverter:   internal.DeducedTypeConverter{},
+		objectConverter: objectConverter,
+		objectDefaulter: objectDefaulter,
+		groupVersion:    gv,
+		hubVersion:      hub,
+		updater: merge.Updater{
+			Converter: internal.NewVersionConverter(internal.DeducedTypeConverter{}, objectConverter, hub),
+		},
+	}
+}
+
 // Update is used when the object has already been merged (non-apply
 // use-case), and simply updates the managed fields in the output
 // object.

staging/src/k8s.io/apiserver/pkg/endpoints/handlers/fieldmanager/internal/typeconverter.go

@@ -23,6 +23,7 @@ import (
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/kube-openapi/pkg/util/proto"
 	"sigs.k8s.io/structured-merge-diff/typed"
+	"sigs.k8s.io/structured-merge-diff/value"
 	"sigs.k8s.io/yaml"
 )
 
@@ -34,6 +35,38 @@ type TypeConverter interface {
 	TypedToObject(typed.TypedValue) (runtime.Object, error)
 }
 
+// DeducedTypeConverter is a TypeConverter for CRDs that don't have a
+// schema. It does implement the same interface though (and create the
+// same types of objects), so that everything can still work the same.
+// CRDs are merged with all their fields being "atomic" (lists
+// included).
+//
+// Note that this is not going to be sufficient for converting to/from
+// CRDs that have a schema defined (we don't support that schema yet).
+type DeducedTypeConverter struct{}
+
+var _ TypeConverter = DeducedTypeConverter{}
+
+// ObjectToTyped converts an object into a TypedValue with a "deduced type".
+func (DeducedTypeConverter) ObjectToTyped(obj runtime.Object) (typed.TypedValue, error) {
+	u, err := runtime.DefaultUnstructuredConverter.ToUnstructured(obj)
+	if err != nil {
+		return typed.TypedValue{}, err
+	}
+	return typed.DeducedParseableType{}.FromUnstructured(u)
+}
+
+// YAMLToTyped parses a yaml object into a TypedValue with a "deduced type".
+func (DeducedTypeConverter) YAMLToTyped(from []byte) (typed.TypedValue, error) {
+	return typed.DeducedParseableType{}.FromYAML(typed.YAMLObject(from))
+}
+
+// TypedToObject transforms the typed value into a runtime.Object. That
+// is not specific to deduced type.
+func (DeducedTypeConverter) TypedToObject(value typed.TypedValue) (runtime.Object, error) {
+	return valueToObject(value.AsValue())
+}
+
 type typeConverter struct {
 	parser *gvkParser
 }
@@ -75,7 +108,11 @@ func (c *typeConverter) YAMLToTyped(from []byte) (typed.TypedValue, error) {
 }
 
 func (c *typeConverter) TypedToObject(value typed.TypedValue) (runtime.Object, error) {
-	vu := value.AsValue().ToUnstructured(false)
+	return valueToObject(value.AsValue())
+}
+
+func valueToObject(value *value.Value) (runtime.Object, error) {
+	vu := value.ToUnstructured(false)
 	u, ok := vu.(map[string]interface{})
 	if !ok {
 		return nil, fmt.Errorf("failed to convert typed to unstructured: want map, got %T", vu)