Caching of currency conversion rates

[onlime]

Hey @amrshawky, great project! This is just the easiest to use and cleanest currency library I found.

Are you planning to implement any kind of caching, so that we don't hit rate limits at exchangerate.host API? I would like to use the default Laravel Cache driver for this, maybe allowing to pass any PSR-6 compliant cache implementation. Caching should ideally be done on both single currency conversions (by e.g. storing from-to currency rates in an array) or for whole rates data (see below).

I didn't find it easy to implement this in your library and pass some caching over to amrshawky/currency through Laravel facade, so for the moment, I am just using this helper class in my project:

<?php

namespace App\Helpers;

use AmrShawky\LaravelCurrency\Facade\Currency;
use Illuminate\Support\Facades\Cache;
use Illuminate\Support\Facades\Log;

class CurrencyCached
{
    /**
     * @var array currency rates
     */
    protected array $rates;

    /**
     * @var string cache key
     */
    protected string $cacheKey = 'currency-rates';

    /**
     * @param int|null $cacheTtl
     */
    public function __construct(int $cacheTtl = null)
    {
        $ttl = $cacheTtl ?? config('app.cache_ttl.currency');
        $this->rates = Cache::remember($this->cacheKey, $ttl, function () {
            return Currency::rates()->latest()->get();
        });
    }

    /**
     * Currency conversion.
     *
     * @param float $amount
     * @param string $toCurrency
     * @param string $fromCurrency
     * @return float|int
     */
    public function convert(float $amount, string $toCurrency = 'CHF', string $fromCurrency = 'EUR')
    {
        return $amount * $this->rates[$toCurrency] / $this->rates[$fromCurrency];
    }
}

Cheers, Philip

[amrshawky]

Hi @onlime,

Thanks for bringing this up, I didn't consider implementing any kind of caching to be honest since it's easy to use it with Laravel cache, But this would be a great feature to add to the library and I'll definitely consider adding it soon.

Thanks.

[DevNack]

Hey everybody, i think you shouldn't because rates may change every minute.

Best

[Shudhanshupatidar]

hey there, I think the rates are not valid. I'm converting USD to ETH and the ETH rates too much