How to configure the expires header if my static file is served by resin?

Server NGINX
1

Hello, all

I use nginx as a reverse proxy and all traffic goes to resin. The
css/js files are also hosted on resin.

Now I want to add the expires directives to css/js, is the following
configuration correct?

location ~ .*.(css|js)$
{
include proxy_params;
proxy_pass http://back_end;
#access_log off;
expires 6h;
}

  location / {
      include proxy_params;
      proxy_pass http://back_end;
  }

thanks.