Overview
At a high level, the system is essentially an event bus - a pipeline that receives events. Rules associated with the event bus evaluate events as they arrive. Each rule checks whether an event matches the rule’s criteria. You associate a rule with a specific event bus, so the rule only applies to events received by that event bus. This follows a Publisher/Subscriber pattern wherein a publisher creates (publishes) an event in the system and any number of subscribers can listen to this event as it happens, according to the rules set up by the subscriber.