public function loadConfigDir($dir, $env = null)
    {
        !$env && $env = $this->name;
        $config = $this->getFileConfig($dir . '/config.php');
        $envConfig = $this->getFileConfig($dir . '/config-' . $env . '.php');
        $config = array_replace_recursive($config, $envConfig);
        $this->wei->setConfig($config);
        return $this;
    }