How to track referrer of referrer in web api

Question

I have this page A - https://example.com/addproduct/

Assume user has come to this page from page B https://referrer.com/.

An ajax request is being fired on this page to create product - /api/products/ [POST].

I will get page A (https://pagea.com/addproduct/) as referrer in this products api but I want to get the referrer of this page A i.e. page B in api. What is the best way to achieve it?

Should I pass this from javascript in request body or http header? Is there any other way?

Answer 1

As long as page A and page B is under your site. When user navigate from page B to page A, you can put an identifier whenever user click navigation element on page B.

Example on page B, you have :

<button onclick="navigate()">Go to page A<button>

Then,

<script type="text/javascript">
   function navigate(){
     var currentLocation = window.location.href;
     window.location = "http://yoursite.com/?addproduct="+currentLocation;
   }
</script>