reverse proxy + basic authentication (no replies)

Hello,

Please excuse me if this has been asked/solved before. I've searched an answer for some good hours but haven't found so i'm trying here.

I have a website on some different server, which does not have any authentication. (So it loads directly the private stuff)
I have configured nginx as a reverse proxy which is pretty clear, and works fine.

Is it possible to configure basic authentication in nginx as the only layer of authentication, and if this is succesfull continue with the reverse proxy role and load the website from a different server?

Thank you!