snipe-it/app/Http/Middleware/CheckForSetup.php

<?php

namespace App\Http\Middleware;

use Closure;
use Config;
use Route;
use Schema;
use App\Models\User;
use App\Models\Setting;

class CheckForSetup
{
    public function handle($request, Closure $next, $guard = null)
    {

            if (Setting::setupCompleted()) {

                if  ($request->is('setup*')) {
                    return redirect(config('app.url'));
                } else {
                    return $next($request);
                }

            } else {
                if (!$request->is('setup*')) {
                    return redirect(config('app.url').'/setup')->with('Request',$request);
                }

                return $next($request);

            }


    }
}