Universal Event Listeners
Universal Event Listeners allow you to write a piece of
Groovy code that controls when an event is triggered, subsequently executing a predefined task.
The Groovy code is periodically executed and when it returns
TRUE, the task is executed.
Table 40.9. Attributes of Universal message task
|Node IDs to handle the event|
In a Cluster environment, each universal event listener has a Node IDs attribute which may be used to specify which Cluster node performs the Groovy code. There are following possibilities:
In a standalone environment, the Node IDs attribute is ignored.
|Interval of check in seconds||Periodicity of Groovy code execution.|
Groovy code that evaluates either to
A piece of Groovy is repeatedly executed and evaluated; based on the result, the event is either triggered and the task executed or no action is taken.
For example, you can continually check for essential data sources before starting a graph. Or, you can do complex checks of a running graph and, for example, decide to kill it if necessary. You can even call the CloverDX Server Core functions using the ServerFacade interface, see Javadoc: http://host:port/clover/javadoc/index.html