Bugsnag session tracking for Symfony projects to allow stability score computing

bugsnag.yml

bugsnag:
  api_key: "%env(BUGSNAG_API_KEY)%"
  app_version: "%env(PROJECT_VERSION)%"

services:
  App\Core\Bugsnag\SessionBugsnagListener:
    arguments:
      - '@service_container'
    tags:
      - { name: "kernel.event_subscriber" }

SessionBugsnagListener.php

<?php

namespace App\Core\Bugsnag;

use Bugsnag\Client;
use InvalidArgumentException;
use Psr\Container\ContainerInterface;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\HttpKernel\Event\GetResponseEvent;
use Symfony\Component\HttpKernel\Event\RequestEvent;
use Symfony\Component\HttpKernel\Event\ResponseEvent;
use Symfony\Component\HttpKernel\HttpKernelInterface;
use Symfony\Component\HttpKernel\KernelEvents;

class SessionBugsnagListener implements EventSubscriberInterface
{

    /** @var Client */
    private $client;
    /** @var ContainerInterface */
    private $container;

    public function __construct(ContainerInterface $container)
    {
        $this->container = $container;
        $this->client = $this->container->get('bugsnag');
    }

    public function onKernelRequest($event)
    {
        // Compatibility with Symfony < 5 and Symfony >=5
        if (!$event instanceof GetResponseEvent && !$event instanceof RequestEvent) {
            throw new InvalidArgumentException('onKernelRequest function only accepts GetResponseEvent and RequestEvent arguments');
        }

        if ($event->getRequestType() !== HttpKernelInterface::MASTER_REQUEST) {
            return;
        }

        $this->client->startSession();
    }

    public function onKernelResponse(ResponseEvent $event)
    {
//        $this->client->getSessionTracker()->sendSessions();
    }

    public static function getSubscribedEvents()
    {
        return [
            KernelEvents::REQUEST => ['onKernelRequest', 256],
            KernelEvents::RESPONSE => ['onKernelResponse', 256]
        ];
    }

}

As stated on Bugsnag's doc, a session for a server-side project is equivalent to : "a request is processed". This snippet achieve this.