private void AssignCurrentStockValue(HoldingsSP500Mapping[] holdingsSP500Mapping)
        {
            var stocksStillHeld = new HashSet <string>();

            Parallel.ForEach(holdingsSP500Mapping, (currenHolding) =>
            {
                if (!currenHolding.SaleDate.HasValue)
                {
                    stocksStillHeld.Add(currenHolding.Ticker);
                }
            });

            var latestQuotes = _stockQuoteService.GetLatestQuoteForStocks(stocksStillHeld).Result;

            Parallel.ForEach(holdingsSP500Mapping, (currentHolding) =>
            {
                if (latestQuotes.ContainsKey(currentHolding.Ticker))
                {
                    currentHolding.CurrentStockValue = latestQuotes[currentHolding.Ticker];
                }
                else
                {
                    currentHolding.CurrentStockValue = 0;
                }
            });
        }
 public IEnumerable <string> Get()
 {
     _stockQuoteService.GetLatestQuoteForStocks(new List <string>()
     {
         "MSFT",
         //"AAPL"
     });
     return(new string[] { "value1", "value2" });
 }