Exchanger and Swap

Interoperability package for Exchanger and Swap.

Installation

composer require peso/peso-exchanger-interop

Usage

The library is essentially 2 classes:

• \Peso\Exchanger\Interop\ExchangerService wraps Peso services to be used in Exchanger

• \Peso\Exchanger\Interop\PesoService wraps Exchanger services to be used in Peso

Peso services in Exchanger

Create a Peso service and pass it to Exchanger:

<?php

use Exchanger\Exchanger;
use Exchanger\ExchangeRateQueryBuilder;
use Peso\Exchanger\Interop\ExchangerService;
use Peso\Services\EuropeanCentralBankService;

$service = new ExchangerService(new EuropeanCentralBankService());
$exchanger = new Exchanger($service);

$query = (new ExchangeRateQueryBuilder('EUR/USD'))
    ->setDate(new DateTimeImmutable('2025-06-13'))
    ->build();

$rate = $exchanger->getExchangeRate($query);

echo $rate->getValue(), PHP_EOL; // 1.1512

Peso services in Swap

Swap is a library that wraps Exchanger so it works too:

<?php

use Peso\Exchanger\Interop\ExchangerService;
use Peso\Services\EuropeanCentralBankService;
use Swap\Builder;

$service = new ExchangerService(new EuropeanCentralBankService());
$swap = (new Builder())
    ->addExchangeRateService($service)
    ->build();

$rate = $swap->historical('EUR/USD', new DateTimeImmutable('2025-06-13'));

echo $rate->getValue(), PHP_EOL; // 1.1512

Exchanger services in Peso

Create an Exchanger service and pass it to Peso:

<?php

use Exchanger\Service\EuropeanCentralBank;
use Peso\Exchanger\Interop\PesoService;
use Peso\Peso\CurrencyConverter;

$service = new PesoService(new EuropeanCentralBank());
$peso = new CurrencyConverter($service);

// 1.1512
echo $peso->getHistoricalConversionRate('EUR', 'USD', '2025-06-13'), PHP_EOL;

Caching

Caching can be tricky due to design differences of Peso and Exchanger. In Peso, caching is a responsibility of a Service. In Exchanger, caching is a responsibility of the Exchanger itself.

• When using Exchanger or Swap with Peso services, a cache can be set on either side or even both:

  <?php
  
  use Peso\Exchanger\Interop\ExchangerService;
  use Peso\Services\EuropeanCentralBankService;
  use Swap\Builder;
  use Symfony\Component\Cache\Adapter\FilesystemAdapter;
  use Symfony\Component\Cache\Psr16Cache;
  
  $cache = new Psr16Cache(new FilesystemAdapter(/* ... */));
  $service = new ExchangerService(
      // Peso-side cache
      new EuropeanCentralBankService($cache)
  );
  
  $exchanger = new Exchanger($service, $cache); // Exchanger-side cache
  // or
  $swap = (new Builder())
      ->addExchangeRateService($service)
      ->useSimpleCache($cache) // Swap-side cache
      ->build();
  

• When using Peso with Exchanger services, the only place to set up a cache is the wrapper itself:

  <?php
  
  use Exchanger\Service\EuropeanCentralBank;
  use Peso\Exchanger\Interop\PesoService;
  use Peso\Peso\CurrencyConverter;
  use Symfony\Component\Cache\Adapter\FilesystemAdapter;
  use Symfony\Component\Cache\Psr16Cache;
  
  $cache = new Psr16Cache(new FilesystemAdapter(/* ... */));
  $service = new PesoService(new EuropeanCentralBank(), $cache);
  $peso = new CurrencyConverter($service);