I tried to use a rewrite policy but It didn't work.
The URL on the client can not change.
I have two pools, one default pool forwarding "/" and another pool to forward the WebSocket and api. My big problem is because of the path on the destination server, /app/api/ and /app/websocket/, when the client access /api/ and /WebSocket/.
It needs to work as a reverse proxy. On Nginx works well using three locations where each location to forward according to proxy_pass.