public async Task <IActionResult> Get(string product, [FromQuery] string targetCurrency)
{
HttpResponseMessage responseProducts = await client.GetAsync("Prices.csv");
responseProducts.EnsureSuccessStatusCode();
HttpResponseMessage responseParities = await client.GetAsync("ExchangeRates.csv");
responseParities.EnsureSuccessStatusCode();
string productsString = await responseProducts.Content.ReadAsStringAsync();
string paritiesString = await responseParities.Content.ReadAsStringAsync();
IEnumerable <Product> products = reader.ParseProducts(productsString);
IEnumerable <Parity> parities = reader.ParseParities(paritiesString);
decimal price = converter.CalculatePrice(product, targetCurrency, products, parities);
return(Ok(new Response(price)));
}