fix field setting

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

util.go

@@ -125,7 +125,9 @@ func newPathRequest(path string, method string, body string, msg interface{}, ta
 				fieldsmap[t.name] = fmt.Sprintf("%v", val.Interface())
 			}
 		} else if (body == "*" || body == t.name) && method != http.MethodGet {
+			if tnmsg.Field(i).CanSet() {
 				tnmsg.Field(i).Set(val)
+			}
 		} else {
 			if val.Type().Kind() == reflect.Slice {
 				for idx := 0; idx < val.Len(); idx++ {