Event applications are designed for task flow or batch processing, and are typically invoked by events, such as scheduled times, system triggers, or external triggers.
In this example, the company's customer relationship management (CRM) system generates a list of subscribers who have opted to receive outage notifications. The list contains customer telephone numbers (MSISDNs) and cities for which an outage-notification service is provided. This list is uploaded to subscriber storage. When a service outage is planned for the city of Dublin, the Process Subscriber state retrieves subscribers from the list. For each subscriber:
Invoke the application, by assigning it to an active event, and creating an event window. Event windows can be one-time or recurring. This application has a one-time event window.
An alternative to manually uploading subscribers to the database is to use an event application to fetch subscribers from the system of record, and use batch processing to upload and store them in the database.