How to forward a request to another URL with all request information (headers, ip etc.)?

Please see below:

1. My app receives request from the user.


2. My app makes an API call to the 3rd party application using request module.

In order 3rd party API to work properly it needs to receive USERS IP and header information. (It's an ad server). But when I send a request through my app -as expected- 3rd party receives my app server's IP and headers.

The question is: How can I make my application's request to the 3rd party API to "seem like" the user? How can I "clone" the request of user's to 3rd party?

Thanks