Laravel将动态子域重定向到文件夹

I creating CMS with function auto-creating subdomains

Example: user pressing button Create domain I adding subdomain name john to DB and creating folder domain.com/subdomains/john.domain.com now i need redirect this subdomain john.domain.com to directory domain.com/subdomains/john.domain.com

code web.php:

if (!function_exists('getSubDomain')) {
    function getSubDomain($url)
    {
        $domain = $url = str_replace(Request::getRequestUri(),'', $url);
        $url = str_replace('http:','',$url);
        $url = str_replace('//','',$url);
        $url = str_replace('www.','',$url);
        $url = str_replace('domain.com','',$url);
        $url = rtrim($url,'.');
        $url = ltrim($url,'.');
        if($url){
            $user = ['john','barry','wells','cisco'];
            if(isset(array_flip($user)[$url])){
                return true;
            }
        }
        return false;
    }
}


Route::group(['domain' => '{sub}.domain.com'], function(){
    if(getSubDomain(Request::url())){

        //Here need redirect to folder.

        echo "Subdomain";
        exit;
    }
});