Laravel make dynamic root at runtime in filesystem

I am trying to upload image from one server to another server. I am using laravel filesystem. I have too many folders for file uploading. I want to make root location dynamic at runtime. But i am not getting any proper solution for this problem. Can anyone help me regarding this problem.

    ['driver' => '','host' => '111.111.11.11','username' => 'root','password' => 'test!@##@!','visibility' => 'public','permPublic' => 0777,'root' => '/var/www/html/tests',    ]