Grep the Euro foreign exchange reference rates from the ECB or openexchangerates.org
Installation with Composer
composer require dwo/exchange_rate_adapter
$adapter = new EcbExchangeRateAdapter();
$exchangeRates = $adapter->getAll();
$adapter = new OpenExchangeRateAdapter($yourAppId);
$exchangeRates = $adapter->getAll();
You will receive an array with the available currencies
array(31) {
["USD"]=>
float(1.0711)
["JPY"]=>
float(127.64)
...
)