Access to host IP and port from container

Hi there!
Question: Is there any possibility to access host IP and random port mapping info inside container?

I have non-common service scenario, my case is cluster for MOBA(multiplayer online battle arena) game.
Each battle runs on individual instance of battle-server(container). Battle-server at start should register itself in registry by providing its public IP and port and its status(BUSY, WAITING).
So I planned to create a service with random port mapping and just scale it to amount of instances depends on current workload. But I didn’t find how to access public IP and random port mapping info within container.
Another variant that I think will work is starting containers with ‘host’ network and give possibility to use any free port to application…
Or maybe someone can suggest better solution?

Thank you!

You can find out information about “self” using rancher-metadata.
curl http://rancher-metadata/latest/self