This class uses a memcached caching DB to find malicious users

ThrottleClass.php

namespace App\Http\Middleware;

use Closure;
use Illuminate\Contracts\Cache\Repository;


class ThrottleMiddleware
{

    public $cache;

    public function __construct(Repository $memcache)
    {
        $this->cache = $memcache;
    }

    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @return mixed
     */
    public function handle($request, Closure $next)
    {

      $ip = $_SERVER['REMOTE_ADDR'];
      $jsonOfRequest = json_encode($request->all());

      // check for blacklisted IP
      $status = $this->cache->get($ip);
      if ( $status === "blacklisted" ) {
        return response('503 Service Unavailable', '503');
      }

      // save unix timestamp of request
      $lastUnixRequest = $this->cache->get('last:'.$ip);
      $this->cache->put('last:'.$ip, time(), 5);

      // grab the most recent requests in 5 minutes
      $recentRequests = ($this->cache->get('recent:' . $ip)) ? intval($this->cache->get('recent:' . $ip)) : 0;
      $totalRequests = ($this->cache->get('total:' . $ip)) ? intval($this->cache->get('total:' . $ip)) : 0;


      // if last submit was less than 15 seconds ago
      if ( $lastUnixRequest >= ( time() - 15 ) ) {

        $lastRequest = $this->cache->get('lastRequest:'.$ip);

        if ( $recentRequests > 5 ) {
          $this->cache->put('watchlist', $ip . ";" . time(), 1200);
        }

        if ( $totalRequests > 50 && $recentRequests > 10 ) {
          $this->cache->forever($ip, "blacklisted");
          $this->cache->forever("blacklist", $ip.";".time());
        }

        if ($lastRequest === $jsonOfRequest) {
          return redirect("forms/repeat-request");
        }

      }


      // store recent requests increment for 5 minute;
      $increasedRecentRequest = $recentRequests + 1;
      $this->cache->put('recent:'.$ip, $increasedRecentRequest, 5);

      // store total requests increment 20 hours
      $increasedTotalRequest = $totalRequests + 1;
      $this->cache->put('total:'.$ip, $increasedTotalRequest, 1200);

      // store request for 1 minute
      $this->cache->put('lastRequest:'.$ip, $jsonOfRequest, 1);

      return $next($request);
    }
}