/// <summary>
/// Gets quotes by executing queries against Yahoo Finance using YQL
/// </summary>
/// <param name="stocks"></param>
/// <returns></returns>
public IEnumerable <StockQuote> GetQuotes(IEnumerable <Stock> stocks)
{
// if no stocks provided, return empty list
if (stocks == null)
{
return(new List <StockQuote>());
}
// enumerate and check count; if no stocks provided, return empty list
var stockList = stocks.ToList();
if (stockList.Count == 0)
{
return(new List <StockQuote>());
}
// get url for query
string queryUrl = _urlProvider.GetQuotesUrl(stockList.Select(s => s.Symbol));
if (string.IsNullOrWhiteSpace(queryUrl))
{
throw new QueryUrlNotProvidedException();
}
// get results of query
string results = _webRequestExecutor.ExecuteRequest(queryUrl);
if (string.IsNullOrWhiteSpace(results))
{
throw new QueryResultsAreEmptyException();
}
// interpret response and return
return(_quotesResultTranslator.TranslateResultsToQuotes(results));
}