public function isEnabled()
    {
        if ($this->enabled === null) {
            $config = $this->app['config'];
            $configEnabled = value($config->get('debugbar.enabled'));

            if ($configEnabled === null) {
                $configEnabled = $config->get('app.debug');
            }

            $this->enabled = $configEnabled && !$this->app->runningInConsole() && !$this->app->environment('testing');
        }

        return $this->enabled;
    }