public function send()
    {
        try {
            $this->requestParams = common_http_Request::currentRequest()->getParams();
            $this->launchData = LtiLaunchData::fromRequest(common_http_Request::currentRequest());
            $baseUrl = null;

            if ($this->requiresRedirect() && !empty($this->getReturnBaseUrl())) {
                $this->errorRedirectResponse();
            } else {
                echo $this->showLtiErrorPage();
            }
        } catch (\Exception $e) {
            $this->renderer->setTemplate(Template::getTemplate('error/error500.tpl', 'tao'));
            echo $this->renderer->render();
        }
    }