Azure Logic Apps + WCF Relay?

How do I connect a Logic App to a Service Bus WCF Relay running on-prem?

Following an (incomplete) tutorial on MSDN/MS Docs, I've successfully create a host and client app that communicate with each other via an Azure WCF Relay. Now, I want a Logic App to communicate with the host on my dev box.

How do I do this? Is this the right approach?