Using web controller to start jobs by name from the job registry with Spring Batch 6

[fmbenhassine]

This was originally posted by @marbon87 here #4866 (comment). I am creating this discussion here in case someone else has the same request.

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Hi @fmbenhassine ,

thanks for your support. We have a webmvc-controller for starting jobs and use the jobregistry with a logic like this:

	@NonNull
	public Optional<JobExecution> start(@NonNull String jobName,
										@NonNull JobParameters jobParameters)
		throws JobInstanceAlreadyCompleteException, JobExecutionAlreadyRunningException, JobParametersConversionException, JobRestartException, InvalidJobParametersException {
		Job job = jobRegistry.getJob(jobName);
		if (job == null) {
			return Optional.empty();
		}
		JobParametersIncrementer jobParametersIncrementer = job.getJobParametersIncrementer();
		if (jobParametersIncrementer != null) {
			jobParameters = jobParametersIncrementer.getNext(jobParameters);
		}
		return jobOperator.start(job, jobParameters);
	}

Do you have an advice how this can be implemented without AutomaticJobRegistrar and JobLoader.

Best regards, Mark

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Please check my answer below.

[fmbenhassine]

Do you have an advice how this can be implemented without AutomaticJobRegistrar and JobLoader.

Yes. JobLoader and AutomaticJobRegistrar are indeed deprecated in v6 and scheduled for removal in v7. The suggested replacement is to use the MapJobRegistry which should be populated as needed at startup with the jobs to operate.

Prior to v6, users had to define the registry as a bean and use a bean post processor or a SmartInitializingSingleton to populate the it before use. v6 simplified this by making MapJobRegistry smart enough to populate itself with jobs from the application context (see #4855). This should be sufficient for most cases, but if it is not the case or if you need to populate the registry with jobs from other contexts or locations, then you can always populate the MapJobRegistry with any mechanism you want (@PostConstruct, InitializingBean, etc) before injecting it in the job operator used by the web controller. You can also provide a custom JobRegistry implementation that is populated as needed at startup.

Please let me know if this helps of if you need further support.