Convert JSON request in Symfony app

JsonRequestListener.php

<?php

namespace Sokil\EventListener;

use Symfony\Component\HttpKernel\Event\GetResponseEvent;
use Symfony\Component\HttpKernel\KernelEvents;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class JsonRequestListener implements EventSubscriberInterface
{
    public function onKernelRequest(GetResponseEvent $event)
    {
        $request = $event->getRequest();
        if ('json' !== $request->getContentType()) {
            return;
        }

        $content = $request->getContent();
        $requestPayload = json_decode($content, true);

        // error decoding request
        if($requestPayload === null && json_last_error() !== JSON_ERROR_NONE) {
            return;
        }
        
        $request->request->replace($requestPayload);
    }

    public static function getSubscribedEvents()
    {
        return array(
            KernelEvents::REQUEST => array(array('onKernelRequest', 16)),
        );
    }
}

services.yaml

services:
  json_request_listener:
    class: Sokil\EventListener\JsonRequestListener
    tags:
      - {name: kernel.event_listener, event: kernel.request, method: onKernelRequest, priority: -255 }