Merge pull request #3 from DrOctavius/main

added non nil uuid graphql scalar

Author: DrOctavius

Diff for: core/listeners/graphql/scalar/scalars.graphqls

@@ -4,4 +4,7 @@ scalar TimeDefault
 scalar TimeRFC3339
 """2006-01-02T15:04:05.999999999Z07:00"""
 scalar TimeRFC3339Nano
-scalar UUID
+
+
+scalar UUID
+scalar NonNilUUID

Diff for: core/listeners/graphql/scalar/uuid_non_nil.go

@@ -0,0 +1,33 @@
+package scalar
+
+import (
+	"fmt"
+	"github.com/99designs/gqlgen/graphql"
+	"github.com/google/uuid"
+	"io"
+)
+
+func MarshalNonNilUUID(u uuid.UUID) graphql.Marshaler {
+	return graphql.WriterFunc(func(w io.Writer) {
+		if u == uuid.Nil {
+			// todo: what to do in this case?!
+		}
+		w.Write([]byte("\"" + u.String() + "\""))
+	})
+}
+
+func UnmarshalNonNilUUID(v interface{}) (uuid.UUID, error) {
+	switch v := v.(type) {
+	case string:
+		_uuid, _err := uuid.Parse(v)
+		if _err != nil {
+			return uuid.Nil, _err
+		}
+		if _uuid == uuid.Nil {
+			return uuid.Nil, fmt.Errorf("%T nil uuid is not permitted", v)
+		}
+		return _uuid, nil
+	default:
+		return uuid.Nil, fmt.Errorf("%T is not a string", v)
+	}
+}