public async Task <RegistrationResponse> RegisterNewUser([FromBody] RegistrationRequest registrationRequest)
        {
            if (await usersClient.IsUserNameExists(registrationRequest.UserName).ConfigureAwait(false))
            {
                return new RegistrationResponse()
                       {
                           Status = RegistrationStatus.UserAlreadyExists,
                       }
            }
            ;

            var newUserId = await usersClient.RegisterNewUserAsync(registrationRequest.UserName, registrationRequest.PasswordHash).ConfigureAwait(false);

            var newSessionId = await sessionsClient.CreateSessionOnUser(newUserId).ConfigureAwait(false);

            return(new RegistrationResponse()
            {
                Status = RegistrationStatus.Registred,
                Sid = newSessionId.ToString(),
                UserName = registrationRequest.UserName
            });
        }