Event message architecture

Integration nodes publish messages on reserved topics after significant events within the integration node. By subscribing to these topics, a client is informed when these events occur.

For each topic, the type of event and message body are explained. The body of these messages is either in JSON or XML format, depending on the topic.

An event publication can contain more than one entry if the topic is the same (for example, if several message flows are created in the same operation).

The general notation of the system topics on which events are published is as follows: 
$SYS/Broker/integrationNodeName/event_type/...
For events that are published that use MQTT as the transport, the notation is as follows:
IBM/IntegrationBus/integrationNodeName/event_type/...
where:
integrationNodeName
is the name of the integration node that issues or raises this event.
event_type
event_type is the type of the event. The following event types are available:
Table 1. Types of event and how they are represented in publication topics. The table describes the event groups, event types, and the equivalent notation for event_type.
Event group Event type Notation format for event_type
OperationalEvents
  • Resource statistics (JSON)
  • Resource statistics (XML)
  • Message flow statistics (JSON)
  • Message flow statistics (XML)
  • Workload Management
  • Statistics/JSON/Resource
  • ResourceStatistics
  • Statistics/JSON
  • StatisticsAccounting
  • WorkloadManagement
AdminEvents
  • Integration node status
  • Integration server status
  • Integration server configuration
  • Status/ExecutionGroup
  • Status
  • Configuration/ExecutionGroup
BusinessEvents
  • Monitoring
  • Monitoring

Message flow statistics and resource statistics event types are published in both JSON and XML format. All other event types are published in XML format.

This specification of topics helps client applications to filter events, which are based on the integration node from which the event originated and the type of event. The client applications register subscriptions for these topics to receive the reports.

For specific events, additional information is included in the topic to help filter on the specific object that raised the event. The inclusion of the string Broker (or for MQTT, IntegrationBus) at the second level of the topic hierarchy allows for future extension to additional subsystems that publish system management events through the integration node.