Is there any OpenHAB API I can use from within OSGi?

Sorry if this has been asked before (it seems such a simple question) but I haven’t found anything about it, and I haven’t got much time left to make a decision.

I work with an OSGI-based platform ( so it seemed a good idea to interact directly with OpenHAB in the samme OSGi container. Is there any OSGI service or exported package that I can use as an API from my OSGI bundle? I am not looking to create a binding, but to interact with the devices in OpenHAB - say, like the REST API, only that it seems too much workaround when both sides are already inside OSGI.