feat(subtypes): Add function to convert protobuf for filtering

This will transform a protobuf message with a oneof for attributes into
the API format to support filtering for list endpoints.

internal/types/subtypes/attribute_transform.go

@@ -130,3 +130,59 @@ func protoToStruct(p proto.Message) (*structpb.Struct, error) {
 	}
 	return st, nil
 }
+
+// Filterable converts a proto.Message so any subtype attributes fields are
+// structed like the API so filter strings will be correctly applied. If the
+// given proto.Message does not have any subtype attributes, the original
+// proto.Message is returned.  To determine if the message needs
+// transformation, it looks for a oneof field named "attrs". It also expects
+// that there is a structpb.Struct field named "attributes" as part of the
+// oneof. Thus the message must be like:
+//
+//    message Foo {
+//      // other fields
+//      oneof attrs {
+//        google.protobuf.Struct attributes = 100;
+//        // other attribute fields
+//      }
+//    }
+//
+// If the message does not conform to this structure,
+// the original message is returned.
+func Filterable(item proto.Message) (proto.Message, error) {
+	clone := proto.Clone(item)
+	r := clone.ProtoReflect()
+
+	attrsField := r.Descriptor().Oneofs().ByName("attrs")
+	if attrsField == nil {
+		return item, nil
+	}
+
+	defaultAttrField := attrsField.Fields().ByName("attributes")
+	if defaultAttrField == nil {
+		return item, nil
+	}
+
+	var attr proto.Message
+	var pbAttrs proto.Message
+	var err error
+
+	oneofField := r.WhichOneof(attrsField)
+	if oneofField == nil {
+		// attrs field is not set, nothing to do
+		return item, nil
+	}
+
+	attr = r.Get(oneofField).Message().Interface()
+	pbAttrs, err = protoToStruct(attr)
+	if err != nil {
+		return nil, err
+	}
+
+	r.Set(defaultAttrField, protoreflect.ValueOfMessage(pbAttrs.ProtoReflect()))
+	f, err := protoToStruct(r.Interface())
+	if err != nil {
+		return nil, err
+	}
+	return f, nil
+}

internal/types/subtypes/attribute_transform_test.go

@@ -0,0 +1,104 @@
+package subtypes
+
+import (
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/hashicorp/boundary/internal/gen/testing/attribute"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/testing/protocmp"
+	"google.golang.org/protobuf/types/known/structpb"
+)
+
+func TestFilterable(t *testing.T) {
+	cases := []struct {
+		name string
+		item proto.Message
+		want proto.Message
+	}{
+		{
+			"TestResource/sub_resource",
+			&attribute.TestResource{
+				Type: "sub_resource",
+				Attrs: &attribute.TestResource_SubResourceAttributes{
+					SubResourceAttributes: &attribute.TestSubResourceAttributes{
+						Name: "test",
+					},
+				},
+			},
+			func() *structpb.Struct {
+				w, _ := structpb.NewStruct(map[string]interface{}{
+					"type": "sub_resource",
+					"attributes": map[string]interface{}{
+						"name": "test",
+					},
+				})
+				return w
+			}(),
+		},
+		{
+			"TestResource/default",
+			&attribute.TestResource{
+				Type: "default",
+				Attrs: &attribute.TestResource_Attributes{
+					Attributes: func() *structpb.Struct {
+						attrs, _ := structpb.NewStruct(map[string]interface{}{
+							"name": "test",
+						})
+						return attrs
+					}(),
+				},
+			},
+			func() *structpb.Struct {
+				w, _ := structpb.NewStruct(map[string]interface{}{
+					"type": "default",
+					"attributes": map[string]interface{}{
+						"name": "test",
+					},
+				})
+				return w
+			}(),
+		},
+		{
+			"TestNoOneOf",
+			&attribute.TestNoOneOf{
+				Type: "sub_resource",
+				Attributes: func() *structpb.Struct {
+					attrs, _ := structpb.NewStruct(map[string]interface{}{
+						"name": "test",
+					})
+					return attrs
+				}(),
+			},
+			&attribute.TestNoOneOf{
+				Type: "sub_resource",
+				Attributes: func() *structpb.Struct {
+					attrs, _ := structpb.NewStruct(map[string]interface{}{
+						"name": "test",
+					})
+					return attrs
+				}(),
+			},
+		},
+		{
+			"TestNoAttributes",
+			&attribute.TestNoAttributes{
+				Id:   "test",
+				Type: "no_attr",
+			},
+			&attribute.TestNoAttributes{
+				Id:   "test",
+				Type: "no_attr",
+			},
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			got, err := Filterable(tc.item)
+			require.NoError(t, err)
+			require.Empty(t, cmp.Diff(got, tc.want, protocmp.Transform()))
+		})
+	}
+}

internal/types/subtypes/attributes.go

@@ -46,7 +46,7 @@ var globalAttributeRegistry attributeRegistry
 // to be called on any protobuf message. However, if a message has subtypes but
 // does not provide a field with a subtype of "default", or if the default
 // field is not a *structpb.Struct type, an error is returned.
-func (ak attributeRegistry) register(d protoreflect.MessageDescriptor) error {
+func (ak *attributeRegistry) register(d protoreflect.MessageDescriptor) error {
 	ak.Lock()
 	defer ak.Unlock()
 
@@ -96,7 +96,7 @@ func (ak attributeRegistry) register(d protoreflect.MessageDescriptor) error {
 // attributeField retrieves the FieldDescriptor for a given subtype's
 // attribute fields. If the corresponding protobuf message has not been
 // registered it will return an error.
-func (ak attributeRegistry) attributeField(d protoreflect.MessageDescriptor, t Subtype) (protoreflect.FieldDescriptor, error) {
+func (ak *attributeRegistry) attributeField(d protoreflect.MessageDescriptor, t Subtype) (protoreflect.FieldDescriptor, error) {
 	ak.RLock()
 	defer ak.RUnlock()
 

internal/types/subtypes/source_registry.go

@@ -35,7 +35,7 @@ type sourceRegistry struct {
 	m map[protoreflect.FullName]protoreflect.FieldDescriptor
 }
 
-func (s sourceRegistry) register(d protoreflect.MessageDescriptor) error {
+func (s *sourceRegistry) register(d protoreflect.MessageDescriptor) error {
 	s.Lock()
 	defer s.Unlock()
 
@@ -58,7 +58,7 @@ func (s sourceRegistry) register(d protoreflect.MessageDescriptor) error {
 	return nil
 }
 
-func (s sourceRegistry) get(d protoreflect.MessageDescriptor) protoreflect.FieldDescriptor {
+func (s *sourceRegistry) get(d protoreflect.MessageDescriptor) protoreflect.FieldDescriptor {
 	s.RLock()
 	defer s.RUnlock()