How to expose existing REST API through Azure Service Bus (or through something else)

Question

I have an existing on-premise REST API from an external vendor. I'd like to expose this API unmodified to the outside world through an Azure website. So I have customers that run this API on-premise and I'm developing a PaaS/SaaS app that should access these on-premise API's.

I also have a client SDK from the external vendor that calls the API. Works without issues when running on-premise. However, now I want to use this SDK from my Azure website.

How do I route REST service calls generated by the SDK to the on-premise API? I thought about using Azure Service Bus WebHttpRelayBinding but this seems to require a WCF contract which I do not have.

In other words: is there a way to send unmodified HTTP traffic to an on-premise system from Azure (through Azure Service Bus or by any other means)?

Answer 1

If you want to access an On-Premise service from the Azure service/websites what you need is a Hybrid Connection.

For that you will need a BizTalk service to redirect the trafic to your on-prem service.

Here are the steps to how to setup a Hybrid connection:

https://azure.microsoft.com/en-us/documentation/articles/web-sites-hybrid-connection-get-started/