Reset scheduled job after completion - spring-batch

Question

I have an scheduled job implemented with Spring batch. Right now when it finishes it doesn't start again because it is detected as completed, is it possible to reset its state after completion?
#Component
class JobScheduler {
#Autowired
private Job job1;
#Autowired
private JobLauncher jobLauncher;
#Scheduled(cron = "0 0/15 * * * ?")
public void launchJob1() throws Exception {
this.jobLauncher.run(this.job1, new JobParameters());
}
}
#Configuration
public class Job1Configuration{
#Autowired
private JobBuilderFactory jobBuilderFactory;
#Autowired
private StepBuilderFactory stepBuilderFactory;
#Bean
public Job job1() {
return this.jobBuilderFactory.get("job1")
.start(this.step1()).on(STEP1_STATUS.NOT_READY.get()).end()
.from(this.step1()).on(STEP1_STATUS.READY.get()).to(this.step2())
.next(this.step3())
.end()
.build();
}
}
I know I can set a job parameter with the time or the id, but this will launch a new execution every 15 minutes. I want to repeat the same execution until is completed without errors, and then, execute a new one.

Answer 1

You can't restart your job because you're setting the job status to COMPLETE by calling end() in .start(this.step1()).on(STEP1_STATUS.NOT_READY.get()).end().
You should instead either fail the job by calling .start(this.step1()).on(STEP1_STATUS.NOT_READY.get()).fail()
or stop the job by calling .start(this.step1()).on(STEP1_STATUS.NOT_READY.get()).stopAndRestart(step1())
Those options will mean the job status is either FAILED or STOPPED instead of COMPLETE which means that if you launch the job with the same JobParameters, it will restart the previous job execution.
See https://docs.spring.io/spring-batch/docs/current/reference/html/step.html#configuringForStop
To launch the job in a way that handles restarting previous instances or starting a new instance, you could look at how the SimpleJobService in spring-batch-admin does it and modify the launch method slightly for your purposes. This requires you to specify an incremental job parameter that is used to launch new instances of your job.
https://github.com/spring-attic/spring-batch-admin/blob/master/spring-batch-admin-manager/src/main/java/org/springframework/batch/admin/service/SimpleJobService.java#L250
#Override
public JobExecution launch(String jobName, JobParameters jobParameters) throws NoSuchJobException,
JobExecutionAlreadyRunningException, JobRestartException, JobInstanceAlreadyCompleteException,
JobParametersInvalidException {
JobExecution jobExecution = null;
if (jobLocator.getJobNames().contains(jobName)) {
Job job = jobLocator.getJob(jobName);
JobExecution lastJobExecution = jobRepository.getLastJobExecution(jobName, jobParameters);
boolean restart = false;
if (lastJobExecution != null) {
BatchStatus status = lastJobExecution.getStatus();
if (status.isUnsuccessful() && status != BatchStatus.ABANDONED) {
restart = true;
}
}
if (job.getJobParametersIncrementer() != null && !restart) {
jobParameters = job.getJobParametersIncrementer().getNext(jobParameters);
}
jobExecution = jobLauncher.run(job, jobParameters);
if (jobExecution.isRunning()) {
activeExecutions.add(jobExecution);
}
} else {
if (jsrJobOperator != null) {
// jobExecution = this.jobExecutionDao
// .getJobExecution(jsrJobOperator.start(jobName, jobParameters.toProperties()));
jobExecution = new JobExecution(jsrJobOperator.start(jobName, jobParameters.toProperties()));
} else {
throw new NoSuchJobException(String.format("Unable to find job %s to launch",
String.valueOf(jobName)));
}
}
return jobExecution;
}

Answer 2

I think the difficulty here comes from mixing scheduling with restartability. I would make each schedule execute a distinct job instance (for example by adding the run time as an identifying job parameter).
Now if a given schedule fails, it could be restarted separately until completion without affecting subsequent schedules. This can be done manually or programmtically in another scheduled method.

Answer 3

This is the solution I came up with after all the comments:
#Component
class JobScheduler extends JobSchedulerLauncher {
#Autowired
private Job job1;
#Scheduled(cron = "0 0/15 * * * ?")
public void launchJob1() throws Exception {
this.launch(this.job1);
}
}
public abstract class JobSchedulerLauncher {
#Autowired
private JobOperator jobOperator;
#Autowired
private JobExplorer jobExplorer;
public void launch(Job job) throws JobExecutionAlreadyRunningException, JobRestartException, JobInstanceAlreadyCompleteException,
JobParametersInvalidException, NoSuchJobException, NoSuchJobExecutionException, JobExecutionNotRunningException, JobParametersNotFoundException, UnexpectedJobExecutionException {
// Get the last instance
final List<JobInstance> jobInstances = this.jobExplorer.findJobInstancesByJobName(job.getName(), 0, 1);
if (CollectionUtils.isNotEmpty(jobInstances)) {
// Get the last executions
final List<JobExecution> jobExecutions = this.jobExplorer.getJobExecutions(jobInstances.get(0));
if (CollectionUtils.isNotEmpty(jobExecutions)) {
final JobExecution lastJobExecution = jobExecutions.get(0);
if (lastJobExecution.isRunning()) {
this.jobOperator.stop(lastJobExecution.getId().longValue());
this.jobOperator.abandon(lastJobExecution.getId().longValue());
} else if (lastJobExecution.getExitStatus().equals(ExitStatus.FAILED) || lastJobExecution.getExitStatus().equals(ExitStatus.STOPPED)) {
this.jobOperator.restart(lastJobExecution.getId().longValue());
return;
}
}
}
this.jobOperator.startNextInstance(job.getName());
}
}
My job now uses an incrementer, based on this one https://docs.spring.io/spring-batch/docs/current/reference/html/job.html#JobParametersIncrementer:
#Bean
public Job job1() {
return this.jobBuilderFactory.get("job1")
.incrementer(new CustomJobParameterIncrementor())
.start(this.step1()).on(STEP1_STATUS.NOT_READY.get()).end()
.from(this.step1()).on(STEP1_STATUS.READY.get()).to(this.step2())
.next(this.step3())
.end()
.build();
}
In my case my scheduler won't start 2 instances of the same job at the same time, so if I detect a running job in this code it means that the server restarted leaving the job with status STARTED, that's why I stop it and abandon it.