[fix] Set `x-forwarded-for` from req.connection.socket.remoteAddress if...

[fix] Set `x-forwarded-for` from req.connection.socket.remoteAddress if req.connection.remoteAddress is not defined

lib/node-http-proxy.js

@@ -346,7 +346,7 @@ HttpProxy.prototype.proxyRequest = function (req, res, options) {
   //
   // Add `x-forwarded-for` header to availible client IP to apps behind proxy
   //
-  req.headers['x-forwarded-for'] = req.connection.remoteAddress;
+  req.headers['x-forwarded-for'] = req.connection.remoteAddress || req.connection.socket.remoteAddress;
   
   //
   // Emit the `start` event indicating that we have begun the proxy operation.