http {
  upstream database {
  postgres_server 127.0.0.1 dbname=stardb user=username password=yourpass;
}


server {
listen 80 default_server;
listen [::]:80 default_server;

location /ip {
    postgres_pass     database;
    rds_json on;

    #postgres_query HEAD GET "SELECT * FROM establishment_view;
    postgres_query    HEAD GET  "SELECT http_host as ip FROM establishment_view where aet = 'NXS_DEV_FLO2'";
    }

    location /port {
        postgres_pass     database;
        rds_json on;

        postgres_query    HEAD GET  "SELECT coalesce(http_port, '80') as port  FROM establishment_view where aet = 'NXS_DEV_FLO2'";
    }