Upstream server stickiness for clients when loadbalancing different connection types

Greetings,

Thanks for reading.

I have an application that needs to be reverse proxied & load balanced

The reverse proxying was achieved quite easily but iam not sure how the load balacing will work due to a complication that we have.

The problem is that the application needs to be accessed via websocket + the HTTP API it supports and a client should ensure they are connected to the same physical server for both. Since the websocket and HTTP API are served from different server applications, they have different ports.

How can Nginx rules be written such that the HTTP API goes to the same upstream physical server for both types of connections (until, that server fails ofcourse).

Any help would be appreciated. Thanks in advance

Rgds