Tracking vanity url's with analytics

We would like to track vanity url usage through analytics. One possible solution that we see is to add the vanity url as query parameter to the resulting url. So for example https://www.my-site.com/my-vanity-url becomes https://www.my-site.com/my/real/page.html?s_url=/my-vanity-url

Is this feasible? What API's could be used to add the vanity url as query parameter to the response. Or is there a better solution?