nginx.conf

events {}

http {
    upstream geoblock {
        server geoblock:8080;
    }

    map $host $backend {
        whoami-1.local whoami-1:80;
        whoami-2.local whoami-2:80;
    }

    server {
        listen 80;
        server_name whoami-1.local whoami-2.local;
        resolver 127.0.0.11;

        location / {
            proxy_pass http://$backend;
            proxy_set_header Host $host;
            auth_request /auth;
        }

        location /auth {
            internal;
            proxy_pass http://geoblock/v1/forward-auth;
            proxy_pass_request_body off;
            proxy_set_header Content-Length "";
            proxy_set_header X-Forwarded-For $remote_addr;
            proxy_set_header X-Forwarded-Host $http_host;
            proxy_set_header X-Forwarded-Method $request_method;
        }
    }
}