public function fetchRate(CurrencyPair $currencyPair)
{
$providerIds = [(int) $this->mainProvider, (int) $this->secondProvider];
/** @var CurrencyRateProvider[] $providers */
$providers = CurrencyRateProvider::find()->where(['id' => $providerIds])->orderBy(['FIELD (`id`, ' . implode(',', $providerIds) . ')' => ''])->all();
if (count($providers) !== 2) {
throw new Exception('One of providers not found');
}
$rates = [];
foreach ($providers as $provider) {
try {
$providerHandler = $provider->getImplementationInstance($this->httpAdapter);
if ($providerHandler !== null) {
$swap = new Swap($providerHandler);
$rate = $swap->quote($currencyPair->getBaseCurrency() . '/' . $currencyPair->getQuoteCurrency())->getValue();
$rates[] = floatval($rate);
} else {
throw new Exception('Provider "' . $provider->name . '" not found');
}
} catch (\Exception $e) {
throw new Exception('One or more currency providers did not return result');
}
}
$min = min($rates);
$max = max($rates);
return new Rate($max - $min >= $max * $this->criticalDifference / 100 ? $max : $rates[0], new \DateTime());
}
