Immutable PHP Currency Converter

The gocanto/converter composer package by Gustavo Ocanto is an immutable PHP currency converter that’s data-agnostic.

Related: Laravel Money is a package for formatting money in Laravel projects.

You need to bring your own database or repository of currency conversion data, and implement a data layer for the conversions. Here’s an example repository from the project:

<?php
 
namespace Gocanto\Converter\Examples;
 
use Gocanto\Converter\CurrencyValue;
use Gocanto\Converter\Interfaces\CurrenciesRepositoryInterface;
 
class CurrenciesRepositoryExample implements CurrenciesRepositoryInterface
{
    /**
     * @param string $code
     * @return CurrencyValue
     */
    public function getCurrentRate(string $code) : CurrencyValue
    {
        // here, you need to write any related logic to query your DB. Once you have this info,
        // you will have to create the currency value object with the valid info as so:
 
        return new CurrencyValue('U.S. Dollars', 'USD', '$', 0.731271);
    }
}

Next, here’s an example of a currency conversion backed by the data repository:

use Gocanto\Converter\Examples\CurrenciesRepositoryExample;
use Gocanto\Converter\Converter;
use Gocanto\Converter\RoundedNumber;
 
$repository = new CurrenciesRepositoryExample;
$converter = new Converter($repository);
 
$conversion = $converter
    ->withAmount(RoundedNumber::make(10))
    ->withCurrency('SGD')
    ->convertTo('USD');

You can learn more about this package, get full installation instructions, and view the source code on GitHub at gocanto/converter.