Once the Event Store is populated, it is available to provide Events to be forwarded as notifications to interested parties. We’ll look at two styles of making these Events available. One style is through RESTful resources that are queried by clients, and the second style is by sending messages over a topic/exchange of a middleware messaging product.
Granted, the REST-based approach is not truly a forwarding technique. Yet, it is used to produce the same results as a Publish-Subscribe style, much as an e-mail client is a “subscriber” to e-mail messages “published” by an e-mail server.