If these properties are in place, the Notification Service will reconnect to all its clients and deliver all non-expired events to its consumers after a crash. With all this added information for each event, we need a general event structure. The structured event defines a standard data structure into which a wide variety of event data can be stored. The structured event is a more strongly typed event message known to the Notification Service and its clients. This structure will allow more efficient processing of the event notification.
Structured events consist of a header and a body.
The header contains two sections. The second section, which is the variable portion of the header, contains optional information about the event. This is constructed as a sequence of properties to hold QoS information related to the individual event notification. The separation of the header into two sections is designed so that a lightweight notification can be created. The filterable part is a sequence of properties.