public IEnumerable<Exchange> GetRange(DateTime startDate, DateTime endDate, string targetCurrencyCode)
{
var exchangesInRange = this.dbSet
.Where(
e =>
startDate <= e.Date && e.Date <= endDate
)
.ToList();
var targetExchanges = exchangesInRange
.Where(
e =>
e.CurrencyCode == targetCurrencyCode
)
.ToList();
var numberOfDaysInRange = (endDate - startDate).Days + 1; // Inclusive.
if (targetExchanges.Count == numberOfDaysInRange)
return targetExchanges;
var availableDatesInRange = exchangesInRange.Select(ex => ex.Date).Distinct();
var availableTargetDates = targetExchanges.Select(ex => ex.Date);
var rangeCount = availableDatesInRange.Count();
var targetCount = availableTargetDates.Count();
if (rangeCount != targetCount)
{
Trace.WriteLine("For the range given there are "+rangeCount+" dates in the db, "+targetCount+" of them are for "+targetCurrencyCode+".");
var resEx = new ExchangeResource.TryRequestingOtherDatesOrCurrency(
"Rates for "+targetCurrencyCode+" are not available for some of the dates requested."
);
var absentTargetDates = availableDatesInRange.Except(availableTargetDates);
resEx.AddFailedDates(absentTargetDates);
throw resEx;
}
Trace.WriteLine(
String.Format("Found rates for {0} out of {1} days in the DB. Let's retrieve the rest!", targetExchanges.Count, numberOfDaysInRange)
);
var currentDate = startDate;
var availableDates = targetExchanges.Select(e => e.Date).ToDictionary(d => d);
var datesToRetrieve = new List<DateTime>(numberOfDaysInRange - targetExchanges.Count);
while (currentDate <= endDate) // Inclusive.
{
if (!availableDates.ContainsKey(currentDate))
{
datesToRetrieve.Add(currentDate);
}
currentDate = currentDate.AddDays(1);
}
Trace.WriteLine("We have " + datesToRetrieve.Count + " dates to retrieve.");
IEnumerable<Exchange> retrievedExchanges;
try
{
Trace.WriteLine("Call to exchange external resource.");
retrievedExchanges = DataAccessLayer.ExchangeResources
.External
.DefaultExternalResource
.RetrieveAndPopulateExchanges(
datesToRetrieve,
targetCurrencyCode,
this.dbSet // TODO: test that if dbSet is populated then it is saved to the db on SaveChanges.
);
}
finally
{
this.exchangeContext.SaveChanges();
}
return targetExchanges.Concat(retrievedExchanges.Where(ex => ex.CurrencyCode == targetCurrencyCode));
}
public IEnumerable <Exchange> GetRange(DateTime startDate, DateTime endDate, string targetCurrencyCode)
{
var exchangesInRange = this.dbSet
.Where(
e =>
startDate <= e.Date && e.Date <= endDate
)
.ToList();
var targetExchanges = exchangesInRange
.Where(
e =>
e.CurrencyCode == targetCurrencyCode
)
.ToList();
var numberOfDaysInRange = (endDate - startDate).Days + 1; // Inclusive.
if (targetExchanges.Count == numberOfDaysInRange)
{
return(targetExchanges);
}
var availableDatesInRange = exchangesInRange.Select(ex => ex.Date).Distinct();
var availableTargetDates = targetExchanges.Select(ex => ex.Date);
var rangeCount = availableDatesInRange.Count();
var targetCount = availableTargetDates.Count();
if (rangeCount != targetCount)
{
Trace.WriteLine("For the range given there are " + rangeCount + " dates in the db, " + targetCount + " of them are for " + targetCurrencyCode + ".");
var resEx = new ExchangeResource.TryRequestingOtherDatesOrCurrency(
"Rates for " + targetCurrencyCode + " are not available for some of the dates requested."
);
var absentTargetDates = availableDatesInRange.Except(availableTargetDates);
resEx.AddFailedDates(absentTargetDates);
throw resEx;
}
Trace.WriteLine(
String.Format("Found rates for {0} out of {1} days in the DB. Let's retrieve the rest!", targetExchanges.Count, numberOfDaysInRange)
);
var currentDate = startDate;
var availableDates = targetExchanges.Select(e => e.Date).ToDictionary(d => d);
var datesToRetrieve = new List <DateTime>(numberOfDaysInRange - targetExchanges.Count);
while (currentDate <= endDate) // Inclusive.
{
if (!availableDates.ContainsKey(currentDate))
{
datesToRetrieve.Add(currentDate);
}
currentDate = currentDate.AddDays(1);
}
Trace.WriteLine("We have " + datesToRetrieve.Count + " dates to retrieve.");
IEnumerable <Exchange> retrievedExchanges;
try
{
Trace.WriteLine("Call to exchange external resource.");
retrievedExchanges = DataAccessLayer.ExchangeResources
.External
.DefaultExternalResource
.RetrieveAndPopulateExchanges(
datesToRetrieve,
targetCurrencyCode,
this.dbSet // TODO: test that if dbSet is populated then it is saved to the db on SaveChanges.
);
}
finally
{
this.exchangeContext.SaveChanges();
}
return(targetExchanges.Concat(retrievedExchanges.Where(ex => ex.CurrencyCode == targetCurrencyCode)));
}