Ngrok with HTTPS on Laravel

app.php

<?php

$middleware->use([
    \App\Http\Middleware\HandleNgrokRequests::class,
]);

AppServiceProvider.php

<?php

public function boot(): void
{
    URL::forceHttps();
    URL::useOrigin('https://' . request()->header('X-Forwarded-Host'));
}

HandleNgrokRequests.php

<?php

declare(strict_types=1);

use Closure;
use Illuminate\Http\RedirectResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\URL;
use Symfony\Component\HttpFoundation\Response;

class HandleNgrokRequests
{
    public function handle(Request $request, Closure $next): Response
    {
        $response = $next($request);

        $ngrokHost = $request->header('X-Forwarded-Host');

        if ($ngrokHost && (str_ends_with($ngrokHost, 'ngrok-free.app') || str_ends_with($ngrokHost, 'ngrok.io'))) {

            if ($response instanceof RedirectResponse) {
                $this->fixRedirectTarget($response, $ngrokHost);
            } elseif ($response->isSuccessful()) {
                $contentType = $response->headers->get('Content-Type', '');

                $isHtml = str_contains($contentType, 'html');
                $isInertiaJson = $request->header('X-Inertia') && str_contains($contentType, 'json');

                if ($isHtml || $isInertiaJson) {
                    $this->fixResponseBody($response, $ngrokHost);
                }
            }
        }

        return $response;
    }

    /**
     * Fixes a redirect URL by rebuilding it.
     */
    private function fixRedirectTarget(RedirectResponse $response, string $ngrokHost): void
    {
        $targetUrl = $response->getTargetUrl();
        $localDomain = config('app.domain');

        if (! empty($localDomain) && str_contains($targetUrl, $localDomain)) {
            $path = parse_url($targetUrl, PHP_URL_PATH) ?? '/';
            $query = parse_url($targetUrl, PHP_URL_QUERY);

            $newTarget = 'https://'.$ngrokHost.$path;
            if ($query) {
                $newTarget .= '?'.$query;
            }

            $response->setTargetUrl($newTarget);
        }
    }

    /**
     * Replaces all occurrences of the local domain in the response body (HTML or JSON).
     */
    private function fixResponseBody(Response $response, string $ngrokHost): void
    {
        $localDomain = config('app.domain');
        if (empty($localDomain)) {
            return;
        }

        $content = $response->getContent();
        if (is_string($content) && str_contains($content, $localDomain)) {
            $escapedDomain = preg_quote($localDomain, '/');
            $pattern = '/(https?:\/\/)([\w.-]+\.'.$escapedDomain.')/';
            $newContent = preg_replace($pattern, 'https://'.$ngrokHost, $content);

            $response->setContent($newContent);
        }
    }
}

start_ngrok.sh

ngrok http --host-header=rewrite subdomain.domain.test:80