vcl 4.0;
import std;

sub vcl_recv {

  # Retrieve WordPress logged in username, store it in a custom http x-header and clean cookie
  if (req.http.Cookie ~ "wordpress_logged_in")  {      
     set req.http.X-UserID = regsuball(req.http.Cookie, "^.*wordpress_logged_in_[^=]+[^;]=([^;]*);*.*$", "\1");
     set req.http.X-UserID = regsuball(req.http.X-UserID, "%7C.*", "");
     # Remove wordpress_logged_in and wordpress_ cookies
     set req.http.Cookie = regsuball(req.http.Cookie, "wordpress_logged_in_[^=]+[^;]+(; )?", "");
  } 

}