private async Task<SearchResultViewModel> CreateSearchResultViewModelAsync(SearchCriteriaModel criteriaModel)
{
var client = __client.Value;
var database = client.GetDatabase("flights");
var collection = database.GetCollection<Flight>("flights");
var aggregateOfFlight = collection.Aggregate();
var filter = CreateFilter(criteriaModel);
if (filter != null)
{
aggregateOfFlight = aggregateOfFlight.Match(filter);
}
var aggregateOfSearchResultViewModel = aggregateOfFlight.Group(
f => 1,
g => new SearchResultViewModel
{
TotalNumberOfFlights = g.Count(),
TotalNumberOfDelayedFlights = g.Sum(f => f.ArrivalDelay > 0.0 ? 1 : 0),
AverageDelayInMinutes = (double)g.Average(f => f.ArrivalDelay > 0.0 ? (double?)f.ArrivalDelay : null)
});
return await aggregateOfSearchResultViewModel.SingleAsync();
}
private FilterDefinition<Flight> CreateFilter(SearchCriteriaModel criteriaModel)
{
var filterBuilder = Builders<Flight>.Filter;
var clauses = CreateClauses(criteriaModel, filterBuilder);
if (clauses.Count > 0)
{
return filterBuilder.And(clauses);
}
else
{
return null;
}
}
public async Task<ActionResult> Search(SearchCriteriaModel criteriaModel)
{
var viewModel = await CreateSearchResultViewModelAsync(criteriaModel);
return View("SearchResultView", viewModel);
}
private List<FilterDefinition<Flight>> CreateClauses(SearchCriteriaModel criteriaModel, FilterDefinitionBuilder<Flight> filterBuilder)
{
var clauses = new List<FilterDefinition<Flight>>();
if (criteriaModel.FromDate != null)
{
var fromDate = DateTime.SpecifyKind(DateTime.Parse(criteriaModel.FromDate), DateTimeKind.Utc);
var clause = filterBuilder.Gte(f => f.FlightDate, fromDate);
clauses.Add(clause);
}
if (criteriaModel.ToDate != null)
{
var toDate = DateTime.SpecifyKind(DateTime.Parse(criteriaModel.ToDate), DateTimeKind.Utc);
var clause = filterBuilder.Lte(f => f.FlightDate, toDate);
clauses.Add(clause);
}
if (criteriaModel.AirlineId != null)
{
var clause = filterBuilder.Eq(f => f.AirlineId, criteriaModel.AirlineId.Value);
clauses.Add(clause);
}
if (criteriaModel.OriginId != null)
{
var clause = filterBuilder.Eq(f => f.OriginAirportId, criteriaModel.OriginId.Value);
clauses.Add(clause);
}
if (criteriaModel.DestinationId != null)
{
var clause = filterBuilder.Eq(f => f.DestinationAirportId, criteriaModel.DestinationId.Value);
clauses.Add(clause);
}
return clauses;
}