public async Task <UserTokenModel> Authenticate(string username, string password) { if (username != null) { var user = (await _unitOfWork.Users.Find(u => u.Email.ToLower() == username.ToLower())).SingleOrDefault(); if (_passwordHashService.Validate(password, user.Password)) { return(new UserTokenModel { Token = CreateToken(user.UserId), UserId = user.UserId }); } } return(null); }