public async Task <UserEntity> Register(UserEntity user, CancellationToken cancellationToken)
{
if (user == null)
{
throw new ArgumentNullException(nameof(user));
}
if (string.IsNullOrEmpty(user.Username))
{
throw new ArgumentException("Username is null!");
}
if (string.IsNullOrEmpty(user.Password))
{
throw new ArgumentException("Password is null!");
}
if ((await _repository.GetByUsername(user.Username, cancellationToken)) != null)
{
throw new ArgumentException($"Username already exists : '{user.Username}'");
}
UserEntity newUser = new UserEntity
{
Username = user.Username,
Password = _dataProtection.HashPassword(user.Password)
};
await _repository.Create(newUser, cancellationToken);
newUser.Password = null;
return(newUser);
}