Exchange

Exchange is PHP script works with currencies. You can convert price.

Here is changelog.

Extension for framework

• Nette extension

Installation via composer

$ composer require h4kuna/exchange

Optional packages

$ composer require guzzlehttp/guzzle guzzlehttp/psr7 h4kuna/dir nette/caching

Support PSR-6 for cache.

How to use

Init object Exchange by ExchangeFactory. Default Driver for read is Cnb, here are others.

For example define own exchange rates:

• 25 CZK = 1 EUR
• 20 CZK = 1 USD

use h4kuna\Exchange\Currency\Property;
use h4kuna\Exchange\Driver\Cnb\Day;
use h4kuna\Exchange\Exchange;
use h4kuna\Exchange\ExchangeFactory;
use h4kuna\Exchange\RatingList\CacheEntity;
use h4kuna\Exchange\RatingList\RatingList;

{ # by factory
	$exchangeFactory = new ExchangeFactory(
		from: 'eur',
		to: 'usd',
		allowedCurrencies: [
			'CZK',
			'USD',
			'eur', // lower case will be changed to upper case
		],
	);

	$exchange = $exchangeFactory->create();
}

{ # custom RatingList
	$ratingList = new RatingList(new DateTimeImmutable(), new DateTimeImmutable(), null, [
		'EUR' => new Property(1, 25.0, 'EUR'),
		'USD' => new Property(1, 20.0, 'USD'),
		'CZK' => new Property(1, 1.0, 'CZK'),
	]);
	$exchange = new Exchange('EUR', $ratingList, 'USD');
}

echo $exchange->change(100) . PHP_EOL; // EUR -> USD = 125.0

// use only upper case
echo $exchange->change(100, 'CZK') . PHP_EOL; // CZK -> USD = 5.0
echo $exchange->change(100, null, 'CZK') . PHP_EOL; // EUR -> CZK = 2500.0
echo $exchange->change(100, 'USD', 'CZK') . PHP_EOL; // USD -> CZK = 2000.0

Change driver and date

Download history exchange rates. Make new instance of Exchange with history rate.

use h4kuna\Exchange\RatingList;
use h4kuna\Exchange;

$exchangePast = $exchangeFactory->create(cacheEntity: new CacheEntity(new Datetime('2000-12-30'), new Day));
echo $exchangePast->change(100) . PHP_EOL;

Access and iterator

use h4kuna\Exchange\Currency\Property;
/* @var $property Property */
$property = $exchange['EUR'];
var_dump($property);
echo PHP_EOL;

foreach ($exchange as $code => $property) {
	/* @var $property Property */
	var_dump($code, $property);
}

Caching

The cache invalid automatic at some time, defined by property SourceData::$refresh. From this property is counted time to live. Little better is invalid cache by cron. Because one request on server does not lock other requests. Let's run cron max. 29 minutes before invalidate cache.

use h4kuna\Exchange\RatingList\RatingListCache;
use h4kuna\Exchange\RatingList\CacheEntity;
use h4kuna\Exchange\Driver\Cnb\Day;

/** @var RatingListCache $ratingListCache */
$ratingListCache->rebuild(new CacheEntity(null, new Day));

In example, is used h4kuna\Exchange\Driver\Cnb\Day::$refresh is defined at 14:30 + 30 minute the cache is valid. Run cron 14:32 every day.