Once your deployment is active, you can test the UrlRewriteFilter by making a simple GET request at the old api 3.1 endpoint from the browser.
Example: (This is a test endpoint)
Success: HTTP CODE 200
welcome to stream manager event route
Once you enter the URL in the browser and hit "Enter", you should see your URL automatically changing to
<streammanagerurl>/streammanager/api/4.0/event/test?action=broadcast in the browser's address bar.