/**
* Returns the exchange rate for two currencies.
* @param string $fromCurrency Currency code to convert from (eg: USD)
* @param string $toCurrency Currency code to convert to (eg: AUD)
* @return int
*/
public function getRate($fromCurrency, $toCurrency)
{
$fromCurrency = trim(strtoupper($fromCurrency));
$toCurrency = trim(strtoupper($toCurrency));
/*
* Look up in the cache
*/
$key = $fromCurrency . '_' . $toCurrency;
if (array_key_exists($key, self::$rateCache)) {
return self::$rateCache[$key];
}
/*
* Look up in the database cache
*/
$converter = ExchangeConverter::getDefault();
if (!$converter->class_name) {
throw new ApplicationException('Currency rate converter is not configured.');
}
$interval = $converter->refresh_interval;
$intervalDate = Carbon::now()->subHours($interval);
$record = ExchangeRate::make()->where('from_currency', $fromCurrency)->where('to_currency', $toCurrency)->where('created_at', '>', $intervalDate);
if ($record = $record->first()) {
return self::$rateCache[$key] = $record->rate;
}
/*
* Evaluate rate using a currency rate converter
*/
try {
$rate = $converter->getExchangeRate($fromCurrency, $toCurrency);
$record = ExchangeRate::make();
$record->from_currency = $fromCurrency;
$record->to_currency = $toCurrency;
$record->rate = $rate;
$record->save();
return self::$rateCache[$key] = $rate;
} catch (Exception $ex) {
/*
* Load the most recent rate from the cache
*/
$record = ExchangeRate::make()->where('from_currency', $fromCurrency)->where('to_currency', $toCurrency)->orderBy('created_at', 'desc');
if (!($record = $record->first())) {
throw $ex;
}
return self::$rateCache[$key] = $record->rate;
}
}
protected function index_onSave()
{
$record = ExchangeConverter::getDefault();
return $this->update_onSave($record->id);
}
