Returns the available flights that match the search criteria(lowest price as default).
Verify the most up-to-date price and availability for the route selected.
Create a booking with the specific route and passenger info.
Verify the book status before payment.
After the customer completed the payment, platform/ota need to inform the DidaTravel that they need to issue ticket.
InformTicket: after DidaTravel issue the ticket,call the url that the customer provided to push ticket infomation.
OrderDetail: get order details once per minute.