code: private function checkContentLengthExceeded(): bool
      {
          if (isset($this->headers['Content-Length'])) {
              if ($this->payload->count() >= $this->headers['Content-Length']) {
                  return true;
              }
          }
          return false;
      }
docs: Check whether the readen bytes amount has reached the
  content length amount
  
  @return bool