Ngninx load balancer help (for http2 url hash balancing)

I would prefer to load use nginx as my load balancer as my app is using uwsgi protocol internally and would like to offer http2 sevices (balanced on url depth). If I use haproxy, I will have to use tcp mode and which will not allow url hash balancing.

The issue is that during service changes, the nginx configuration will need to be changed.

I was wondering if somebody could point me to the right resources to fetch rancher-metadata on service upgrades, scaling and such so that I can rewrite/reload the nginx configuration.