Updated the external interface

exchange_rates.go

@@ -20,7 +20,7 @@ var DefaultTimeout = 5 * time.Second
 // ExchangeRates returs the list exchange rates
 func ExchangeRates() (map[string]float64, error) {
 
-	var rates ExchangeRate
+	var rates exchangeRate
 
 	ratesMap := make(map[string]float64, 0)
 

exchange_rates_model.go

@@ -0,0 +1,24 @@
+package ydfinance
+
+// exchangeRate defines the exchange rate
+type exchangeRate struct {
+	Time  string             `xml:"time"`
+	Cubes []exchangeRateCube `xml:"Cube"`
+}
+
+// exchangeRateCube defines an exchange rate cube
+type exchangeRateCube struct {
+	TimedCubes []exchangeRateTimedCube `xml:"Cube"`
+}
+
+// exchangeRateTimedCube defines an exchange rate timed cube
+type exchangeRateTimedCube struct {
+	Time  string                     `xml:"time,attr"`
+	Rates []exchangeRateCurrencyCube `xml:"Cube"`
+}
+
+// exchangeRateCurrencyCube defines an exchange rate currency cube
+type exchangeRateCurrencyCube struct {
+	Currency string  `xml:"currency,attr"`
+	Rate     float64 `xml:"rate,attr"`
+}