Use Marshal and UnmarshalJSON for HexBytes

libs/bytes/bytes.go

@@ -69,3 +69,24 @@ func (bz HexBytes) Format(s fmt.State, verb rune) {
 		s.Write([]byte(fmt.Sprintf("%X", []byte(bz))))
 	}
 }
+
+func (bz HexBytes) MarshalJSON() ([]byte, error) {
+	s := strings.ToUpper(hex.EncodeToString(bz))
+	jbz := make([]byte, len(s)+2)
+	jbz[0] = '"'
+	copy(jbz[1:], s)
+	jbz[len(jbz)-1] = '"'
+	return jbz, nil
+}
+
+func (bz *HexBytes) UnmarshalJSON(data []byte) error {
+	if len(data) < 2 || data[0] != '"' || data[len(data)-1] != '"' {
+		return fmt.Errorf("invalid hex string: %s", data)
+	}
+	bz2, err := hex.DecodeString(string(data[1 : len(data)-1]))
+	if err != nil {
+		return err
+	}
+	*bz = bz2
+	return nil
+}