some_random_error_controller.php

/**
 * @see \Symfony\Component\HttpKernel\Controller\ErrorController
 */
final class ErrorController
{
    private bool $debug = false;
    private ErrorRendererInterface $errorRenderer;
    private Environment $twig;

    /**
     * Default constructor
     */
    public function __construct(ErrorRendererInterface $errorRenderer, Environment $twig, bool $debug = false)
    {
        $this->debug = $debug;
        $this->errorRenderer = $errorRenderer;
        $this->twig = $twig;
    }

    /**
     * Show the error.
     */
    public function show(Request $request, \Throwable $exception, DebugLoggerInterface $logger = null): Response
    {
        if ($exception instanceof HttpExceptionInterface) {
            $code = $exception->getStatusCode();
        } else {
            $code = $exception->getCode();
        }

        $template = null;
        $httpStatusCode = 500;

        if (403 === $code) {
            $httpStatusCode = 403;
            $template = '@gestion/error/error403.html.twig';
        } elseif (404 === $code) {
            $httpStatusCode = 404;
            $template = '@gestion/error/error404.html.twig';
        } elseif (!$this->debug) {
            $template = '@gestion/error/error.html.twig';
        } elseif ('Symfony BrowserKit' === $request->headers->get('User-Agent')) {
            // Debug mode, et test unitaires, c'est safe de faire ça ici.
            return new Response(
                $this->flattenNormalizerExceptionTrace(
                    $this->normalizeExceptionTrace($exception)
                ),
                $httpStatusCode
            );
        }

        foreach ($request->getAcceptableContentTypes() as $contentType) {
            // Always let HTML pass.
            if (false !== \strpos($contentType, 'html')) {
                break;
            }
            if ('application/json' === $contentType) {
                $responseData = [
                    'code' => $code,
                    'message' => $exception->getMessage(),
                ];
                if ($this->debug) {
                    $responseData['trace'] = $this->normalizeExceptionTrace($exception);
                }

                return new JsonResponse($responseData, $httpStatusCode);
            }
        }

        if ($template) {
            // $this->getAndCleanOutputBuffering($request->headers->get('X-Php-Ob-Level', -1));

            return new Response($this->twig->render($template, ['exception' => $exception]), $httpStatusCode);
        }

        // Cut and pasted code from \Symfony\Component\HttpKernel\Controller\ErrorController
        $exception = $this->errorRenderer->render($exception);

        return new Response($exception->getAsString(), $exception->getStatusCode(), $exception->getHeaders());
    }
}