Events are changes in the states or attributes of the objects that Orchestrator finds in the plugged-in technology. Orchestrator monitors events by implementing event handlers.
Orchestrator plug-ins allow you to monitor events in a plugged-in technology in different ways. The Orchestrator plug-in API allows you to create the following types of event handlers to monitor events in a plugged-in technology.
- Passively monitor objects in the plugged-in technology for changes in their state. The plugged-in technology or the plug-in implementation defines the events that listeners monitor. Listeners do not initiate events, but notify Orchestrator when the events occur. Listeners detect events either by polling the plugged-in technology or by receiving notifications from the plugged-in technology. When events occur, Orchestrator policies or workflows that are waiting for the event can react by starting operations in the Orchestrator server. Listener components are optional.
- Monitor certain events in the plugged-in technology and start operations in the Orchestrator server if the events occur. Policies can monitor policy triggers and policy gauges. Policy triggers define an event in the plugged-in technology that, when it occurs, causes a running policy to start an operation in the Orchestrator server, for example running a workflow. Policy gauges define ranges of values for the attributes of an object in the plugged-in technology that, when exceeded, cause Orchestrator to start an operation. Policies are optional.
- Workflow triggers
- If a running workflow contains a Wait Event element, when it reaches that element it suspends its run and waits for an event to occur in a plugged-in technology. Workflow triggers define the events in the plugged-in technology that Waiting Event elements in workflows await. You register workflow triggers with watchers. Workflow triggers are optional.
- Watch workflow triggers for a certain event in the plugged-in technology, on behalf of a Waiting Event element in a workflow. When the event occurs, the watchers notify any worklows that are waiting for that event. Watchers are optional.