When i wanted to het the current hostname of the application in nodejs I always got back ```localhost``` and not the real hostname.. This was because it was behind an Apache webserver :D solution below

get current hostname even if behind ngix or apache (nodejs with express)

var hostname = req.headers['x-forwarded-server'];
                if (typeof hostname == "undefined") {
                    hostname = ( req.headers.host.match(/:/g) ) ? req.headers.host.slice(0, req.headers.host.indexOf(":")) : req.headers.host;
                }