Recoverability: Do task resume after VM shutdown?

[trung]

Hi,

My main use case is to run onetime task but it could be long-running one.
The question that I have is if the VM shutdown (either gracefully or not). Would the incomplete onetime task be resumed to execution?

Regards,

Trung

[kagkarlsson]

The best way is to gracefully stop the task and resume it again later. There is a similar example here: https://github.com/kagkarlsson/db-scheduler/blob/master/examples/spring-boot-example/src/main/java/com/github/kagkarlsson/examples/boot/config/LongRunningJobConfiguration.java#L89

Need to regularly check executionContext.getSchedulerState().isShuttingDown() in the loop, and return a CompletionHandler that persists the progress and reschedules to a later time (might be Instant.now() for immediate pick by another scheduler)

If not done gracefully, i.e. the CompletionHandler is never called, the task will eventually be detected as "dead" and be handled according to its DeadExecutionHandler (which by defaults reschedules to now() I think)