Корректный, хоть и грубый захват JSON'а

src/endpoints_handlers/AuthRegistrationExecutor.h

@@ -33,14 +33,16 @@ public:
     auto body = req.body();
     object json_as_object = json::parse(body).as_object();
 
-    std::string login = serialize(json_as_object.at("login").as_string());
-    std::string password = serialize(json_as_object.at("password").as_string());
+    std::string login = json_as_object.at("login").as_string().c_str();
+    std::string password = json_as_object.at("password").as_string().c_str();
 
     User user;
 
     user.SetLogin(login);
     user.SetPassword(password);
 
+    user_dao_->GetByLogin(login);
+
     http::response<ResponseType> res{
         http::status::ok, req.version()
       };