When should a process start or a service be activated? The trigger can be a requirement in an application, process, or service that then invokes the service or process. However, frequently the link is not that straightforward. When 'something happens' (a business event!), that should lead to the start of other actions or the continuation or redirection of running processes. However, whose responsibility is it to determine that a business event has taken place, and even more importantly, who to notify? The process instance that happens to produce an event should not bare the burden of finding out who needs to be notified—especially as the list of interested parties can be hugely dynamic. Nor should the event be presented to any service, composite application, or process to check out whether perhaps it wants to consume it.
This session discusses Event-Driven SOA—an architecture where applications, processes, and services can produce business events, and interested consumers are notified of those events—through the mediation by the SOA Suite 11g Event Delivery Network (EDN). In this session, we will see how business events are defined across the enterprise, and how an interest in specific types of business events (with specific payloads) can be registered. The session demonstrates how events can be produced, how they are processed by the EDN, and handed to the interested parties. Special attention is given to the correlation of events, ensuring that the correct composite instance is provided with the event. We will discuss how the events can not only originate within the SOA Suite, but also outside of it, through AQ, PL/SQL and Java, ADF BC, and JMS. As a last step, we will discuss Complex Event Processing (CEP) as a potential source of business events. CEP will handle large volumes of small, usually insignificant events. However, by filtering, aggregating, and analyzing for deviations and threshold transgressions, CEP will occasionally find business events that are subsequently sent to the Event Delivery Network. This session has many demonstrations (end-to-end).