How to launch Spring Batch Job Asynchronously

Question

I have followed the spring batch doc and couldn't get my job running Asynchronously.

So I am running the Job from a web container and the job will be triggered via a REST end point.

I wanted to get the JobInstance ID to pass it in response before completing the whole job. So they can check the status of the job later with the JobInstance ID instead of waiting. But I couldn't get it work. Below is the sample code I tried. Please let me know what am I missing or wrong.

BatchConfig to make Async JobLauncher

@Configuration
public class BatchConfig {

    @Autowired
    JobRepository jobRepository;


    @Bean
    public JobLauncher simpleJobLauncher() throws Exception {
        SimpleJobLauncher jobLauncher = new SimpleJobLauncher();
        jobLauncher.setJobRepository(jobRepository);
        jobLauncher.setTaskExecutor(new SimpleAsyncTaskExecutor());
        jobLauncher.afterPropertiesSet();
        return jobLauncher;
    }
}

Controller

@Autowired
JobLauncher jobLauncher;

@RequestMapping(value="/trigger-job", method = RequestMethod.GET)
public Long workHard() throws Exception {
    JobParameters jobParameters = new JobParametersBuilder().
            addLong("time", System.currentTimeMillis())
            .toJobParameters();
    JobExecution jobExecution = jobLauncher.run(batchComponent.customJob("paramhere"), jobParameters);
    System.out.println(jobExecution.getJobInstance().getInstanceId());
    System.out.println("OK RESPONSE");
    return jobExecution.getJobInstance().getInstanceId();
}

And JobBuilder as component

@Component
public class BatchComponent {

    @Autowired
    private JobBuilderFactory jobBuilderFactory;

    @Autowired
    private StepBuilderFactory stepBuilderFactory;

    public Job customJob(String someParam) throws Exception {
        return jobBuilderFactory.get("personProcessor")
                .incrementer(new RunIdIncrementer()).listener(listener())
                .flow(personPorcessStep(someParam)).end().build();
    }


    private Step personPorcessStep(String someParam) throws Exception {
        return stepBuilderFactory.get("personProcessStep").<PersonInput, PersonOutput>chunk(1)
                .reader(new PersonReader(someParam)).faultTolerant().
                        skipPolicy(new DataDuplicateSkipper()).processor(new PersonProcessor())
                .writer(new PersonWriter()).build();
    }


    private JobExecutionListener listener() {
        return new PersonJobCompletionListener();
    }

    private class PersonInput {
        String firstName;

        public PersonInput(String firstName) {
            this.firstName = firstName;
        }

        public String getFirstName() {
            return firstName;
        }

        public void setFirstName(String firstName) {
            this.firstName = firstName;
        }
    }

    private class PersonOutput {
        String firstName;

        public String getFirstName() {
            return firstName;
        }

        public void setFirstName(String firstName) {
            this.firstName = firstName;
        }
    }

    public class PersonReader implements ItemReader<PersonInput> {
        private List<PersonInput> items;
        private int count = 0;

        public PersonReader(String someParam) throws InterruptedException {
            Thread.sleep(10000L); //to simulate processing
            //manipulate and provide data in the read method
            //just for testing i have given some dummy example
            items = new ArrayList<PersonInput>();
            PersonInput pi = new PersonInput("john");
            items.add(pi);
        }

        @Override
        public PersonInput read() {
            if (count < items.size()) {
                return items.get(count++);
            }
            return null;
        }
    }


    public class DataDuplicateSkipper implements SkipPolicy {

        @Override
        public boolean shouldSkip(Throwable exception, int skipCount) throws SkipLimitExceededException {
            if (exception instanceof DataIntegrityViolationException) {
                return true;
            }
            return true;
        }
    }


    private class PersonProcessor implements ItemProcessor<PersonInput, PersonOutput> {

        @Override
        public PersonOutput process(PersonInput item) throws Exception {
            return null;
        }
    }

    private class PersonWriter implements org.springframework.batch.item.ItemWriter<PersonOutput> {
        @Override
        public void write(List<? extends PersonOutput> results) throws Exception {
            return;
        }
    }

    private class PersonJobCompletionListener implements JobExecutionListener {
        public PersonJobCompletionListener() {
        }

        @Override
        public void beforeJob(JobExecution jobExecution) {

        }

        @Override
        public void afterJob(JobExecution jobExecution) {
            System.out.println("JOB COMPLETED");
        }
    }
}

Main Function

@SpringBootApplication
@EnableBatchProcessing
@EnableScheduling
@EnableAsync
public class SpringBatchTestApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringBatchTestApplication.class, args);
    }
}

I am using annotation based configurations and use gradle with the below batch package.

compile('org.springframework.boot:spring-boot-starter-batch')

Please let me know if some more info needed. I couldn't find any example to run this common use case.

Thanks for you time.

Answer 1

Try this,In your Configuration You need to create customJobLauncher with SimpleAsyncTaskExecutor using the @Bean(name = "myJobLauncher") and same will be used @Qualifier in your controller.

@Bean(name = "myJobLauncher")
public JobLauncher simpleJobLauncher() throws Exception {
    SimpleJobLauncher jobLauncher = new SimpleJobLauncher();
    jobLauncher.setJobRepository(jobRepository);
    jobLauncher.setTaskExecutor(new SimpleAsyncTaskExecutor());
    jobLauncher.afterPropertiesSet();
    return jobLauncher;
}

In your Controller

@Autowired
@Qualifier("myJobLauncher")
private JobLauncher jobLauncher;