/// <summary>
/// Polls the current session for quotes.
/// <returns>
/// The <c>Quote</c> instances for this search.
/// </returns>
/// </summary>
private async Task <IList <Quote> > PollCurrentSession()
{
// Flag to track if TripAdvisor API has completed compiling results
bool complete = false;
// Container for the flight quotes
var flightCollection = new List <Quote>();
// Build request URL for current session
string url = TripAdvisorUrlBuilder.BuildPollUrl(_sessionId);
do
{
// Wait 1 second to avoid excessive API calls.
// The free TripAdvisor API has a limit, so we need to avoid
// wasting calls.
Thread.Sleep(1000);
// Query TripAdvisor API
var jsonResponse = await MakeHTTPRequestRaw(url);
// Build quote parser for json payload
var flightParser = new TripAdvisorPayloadParser(jsonResponse);
// Parse the payload into quote instances
var flights = flightParser.GetQuoteData();
// Add the batch of flight quotes
flightCollection.AddRange(flights);
// Check if the TripAdvisor API has signaled completion
if (flightParser.IsComplete())
{
complete = true;
}
} while (!complete); // Iterate until TripAdvisor is done
// Return the flight quotes, dropping duplicates
return(flightCollection
.GroupBy(x => new
{
x.Key,
x.Cost.CurrencyType,
x.Cost.Value,
x.DepartureAirline,
x.DepartureArrivalTime,
x.DepartureStopCount,
x.DepartureTakeoffTime,
x.ReturnAirline,
x.ReturnArrivalTime,
x.ReturnStopCount,
x.ReturnTakeoffTime,
x.ReturnFlightNumber,
x.DepartureFlightNumber
})
.Select(x => x.First())
.ToList());
}
/// <summary>
/// Creates a session for the search parameters.
/// <param name="origin">The name of the origin </param>
/// <param name="destination">The name of the destination airport.</param>
/// <param name="departureDate">The date that the flight will depart from the origin airport.</param>
/// <returns>
/// An awaitable Task instance.
/// </returns>
/// </summary>
private async Task CreateSession(string origin, string destination, DateTime departureDate)
{
// Get airport objects from names
var originAirport = GetAirportFromAirportName(origin);
var destinationAirport = GetAirportFromAirportName(destination);
// Build Url to request the creation of the session
string url = TripAdvisorUrlBuilder.BuildSessionUrl(
originAirport.IataCode,
destinationAirport.IataCode,
departureDate);
// Send request to create session
var response = await MakeHTTPRequest <CreateSessionResponse>(url);
// Extract session Id for later polling
_sessionId = response.search_params.sid;
}
