Does nginx have a Routing API?

I am trying to see if nginx (OSS, not commercial) can be used not only
as a
load balancer, but as a network router/switch in the event that I need
shut my app down and redirect traffic to a CDN/static page, etc.

I was hoping to find a REST API that might allow me to configure routing
rules on the fly but alas, I see nothing.

Does nginx provide this functionality out of the box? Or can I pair it
something that does? This would be a Java app it is balancing, and I see
there is an nginx-clojure
(GitHub - nginx-clojure/nginx-clojure: Nginx module for embedding Clojure or Java or Groovy programs, typically those Ring based handlers.)
module. So perhaps I could expose a REST endpoint through Java (running
the nginx server) somehow…thoughts?

Posted at Nginx Forum: