Customer registration with invitation code only

[ChMa]

Hallo together 🙂 Is it possible to implement a functionality at Shopify so that you can just register when you have received a code from an existing member or from the company direct? So it should work like BestSecret. When you clicking in registration on the website you have to insert a code, so that you have the possibility to register. If you don't have a code, you can't register. 

Thanks for your help!

Christian