checkIdParameterIsValid(eventId, UserErrorCode.INVALID_NOTFOUND, UserErrorCode.INVALID_NOTFOUND);
ParticipantsListTransaction transaction = new ParticipantsListTransaction(user, eventId);
transaction.execute();
EventEx event = transaction.getEvent();
List<Pair<EventTicket, EventTicketHolderList>> ticketAndHolders = transaction.getTicketAndHolders();
Map<String, List<String>> userTicketInfoMap = transaction.getUserTicketInfoMap();
try {
byte[] body = createCSVInputStream(event, ticketAndHolders, userTicketInfoMap);