func_get_args hash cache key example

cache_key.php

<?php

function getProductData(int $productId, string ... $predicates)
{
    $args = func_get_args();
    $hash = '';
    foreach ($args as $arg){
        $hash .= (string)($arg);
    }

    $cacheKey = md5($hash);

    //@todo -> fetch data form external service on cache miss and update the cache
}