private static async Task Run(IReadOnlyList <string> Arguments)
{
// Configure JSON.NET and Refit.
_httpClient = new HttpClient(new CacheBustingMessageHandler())
{
BaseAddress = new Uri(_mappingServiceUrlBase)
};
_jsonSerializer = new JsonSerializer();
_mappingService = RestService.For <IMappingService>(_httpClient);
JsonConvert.DefaultSettings = () => new JsonSerializerSettings
{
// Preserve case of property names.
ContractResolver = new Newtonsoft.Json.Serialization.DefaultContractResolver(),
// Preserve cyclical object references.
PreserveReferencesHandling = PreserveReferencesHandling.All
};
Func <Task <GetOpenServiceCallsResponse> > getOpenServiceCalls = ParseCommandLine(Arguments);
do
{
// Call web service using specified function, then verify object references are preserved.
Stopwatch stopwatch = Stopwatch.StartNew();
GetOpenServiceCallsResponse response = await getOpenServiceCalls();
stopwatch.Stop();
Console.WriteLine($"Retrieved {response.ServiceCalls.Count} service calls, {response.Customers.Count} customers, and {response.Technicians.Count} technicians in {stopwatch.Elapsed.TotalSeconds:0.000} seconds.");
VerifyObjectReferencesPreserved(response);
} while (string.IsNullOrWhiteSpace(Console.ReadLine()));
}
public async Task <GetOpenServiceCallsResponse> GetOpenServiceCallsAsync()
{
var response = new GetOpenServiceCallsResponse();
// Each row in SQL result represents a unique service call but may contain duplicate customers and technicians.
const string sql = @"select sc.Id, sc.Scheduled, sc.[Open], c.Id, c.Name, c.Address, c.City, c.State, c.ZipCode, t.Id, t.Name
from ServiceCalls sc
inner join Customers c on sc.CustomerId = c.Id
inner join Technicians t on sc.TechnicianId = t.Id
where sc.[Open] = 1";
using (var connection = new SqlConnection(_appSettings.Database))
{
await connection.OpenAsync();
await connection.QueryAsync <ServiceCall, Customer, Technician, ServiceCall>(sql, (ServiceCall, Customer, Technician) =>
{
// This lambda method runs once per row in SQL result.
response.ServiceCalls.Add(ServiceCall);
// Reference existing customers and technicians or add to collection if first time encountered.
if (!response.Customers.TryGetValue(Customer.Id, out var customer))
{
// Customer mapped by Dapper not in collection.
customer = Customer;
response.Customers.Add(customer);
}
if (!response.Technicians.TryGetValue(Technician.Id, out var technician))
{
// Technician mapped by Dapper not in collection.
technician = Technician;
response.Technicians.Add(technician);
}
// Configure relationships among objects.
ServiceCall.Customer = customer;
ServiceCall.Technician = technician;
customer.ServiceCalls.Add(ServiceCall);
if (!customer.Technicians.Contains(technician.Id))
{
// Technician not found in customer's collection.
customer.Technicians.Add(technician);
}
technician.ServiceCalls.Add(ServiceCall);
if (!technician.Customers.Contains(customer.Id))
{
// Customer not found in technician's collection.
technician.Customers.Add(customer);
}
return(null);
});
}
return(response);
}
private static void VerifyObjectReferencesPreserved(GetOpenServiceCallsResponse Response)
{
const int technicianId = 3276;
const int customerId = 75904;
const int serviceCallId = 8949862;
var technician = Response.Technicians[technicianId];
var customer = Response.Customers[customerId];
var serviceCall = Response.ServiceCalls[serviceCallId];
Trace.Assert(ReferenceEquals(technician, customer.Technicians[technicianId]));
Trace.Assert(ReferenceEquals(technician, serviceCall.Technician));
Trace.Assert(ReferenceEquals(customer, technician.Customers[customerId]));
Trace.Assert(ReferenceEquals(customer, serviceCall.Customer));
Trace.Assert(ReferenceEquals(serviceCall, technician.ServiceCalls[serviceCallId]));
Trace.Assert(ReferenceEquals(serviceCall, customer.ServiceCalls[serviceCallId]));
}
