public override Task <BuyTicketsResponse> BuyTickets(BuyTicketsRequest request, ServerCallContext context)
{
var user = (User)context.GetHttpContext().Items["User"];
if (user == null)
{
throw new ArgumentNullException(nameof(user));
}
return(Task.FromResult(new BuyTicketsResponse
{
Success = _ticketRepository.BuyTickets(user.Username, request.Count)
}));
}