UpdateBooking method

// Request to update a Booking.
message UpdateBookingRequest {
  // The booking to be updated
  // The following fields can be set in a booking:
  // - status, to cancel a booking.
  // - one of the following is required:
  //   - start_time AND duration in the slot, to reschedule a booking.
  //   - party_size (for dining reservations).
  Booking booking = 1;
}

// Response with the updated Booking.
message UpdateBookingResponse {
  // The updated booking (required)
  Booking booking = 1;

  // The updated user payment option originally used to pay for this booking.
  // This should be set if the UpdateBookingRequest results in a change to
  // the UserPaymentOption.
  // For instance, if the booking is canceled, the UserPaymentOption should
  // reflect an additional credit to the user. In the case of a multi-use
  // payment option, the current_count should be increased by one to
  // allow the user to create another booking with this payment option. In the
  // case of a single-use payment option, a new single-use user payment option
  // should be returned. (required if altered in update)
  UserPaymentOption user_payment_option = 2;

  // If updating a booking fails, this field should reflect the business logic
  // error (e.g., booking is not cancellable) (required if failure occurs)
  BookingFailure booking_failure = 3;
}