Spring batch error tolerance

Question

I'm trying to import city data from a csv file, some data may be duplicated which invoke conflict error ERROR: duplicate key value violates unique constraint "city__unique_idx" Detail: Key (country, city_name, latitude, longitude)=(231, Monticello, 30.5450000000000017, -83.8703000000000003) already exists. 2018-03-13 14:34:03.607 ERROR 13275 --- [ main] o.s.batch.core.step.AbstractStep : Encountered an error executing step cityStep1 in job importCityJob. I want to know how to ignore this error and keep the job running because it currently exits immediately.

Writer:

@Bean
public ItemWriter<City> cityWriter(EntityManagerFactory factory) {
    JpaItemWriter<City> writer = new JpaItemWriter<>();
    writer.setEntityManagerFactory(factory);
    return writer;
}

Here is my job method:

@Bean
public Step cityStep1(ItemWriter<City> writer) {
    return stepBuilderFactory.get("cityStep1").<City, City>chunk(10).reader(cityReader())
            .processor(cityProcessor()).writer(writer).build();
}

@Bean
public Job importHotelJob(JobCompletionNotificationListener listener, Step cityStep) {
    return jobBuilderFactory.get("importCityJob").incrementer(new RunIdIncrementer())
            .listener(listener)
            .next(cityStep1)
            .build();

Thanks.

Edit1:

After I applied faultTolerant()

@Bean
public Step cityStep1(ItemWriter<City> writer) {
    return stepBuilderFactory.get("cityStep1").<City, City>chunk(50).reader(cityReader())
            .processor(cityProcessor()).writer(writer)
            .faultTolerant()
            .skip(ConflictException.class)
            .skip(ConstraintViolationException.class)
            .noRetry(ConflictException.class)
            .noRetry(ConstraintViolationException.class)
            .skipLimit(150)
            .build();

I still get error:

2018-03-14 15:49:40.047 ERROR 26613 --- [           main] o.h.engine.jdbc.spi.SqlExceptionHelper   : ERROR: duplicate key value violates unique constraint "city__unique_idx"
  Detail: Key (country, city_name, latitude, longitude)=(231, Monticello, 30.5450000000000017, -83.8703000000000003) already exists.
2018-03-14 15:49:40.161 ERROR 26613 --- [           main] o.s.batch.core.step.AbstractStep         : Encountered an error executing step cityStep1 in job importCityJob
org.springframework.retry.ExhaustedRetryException: Retry exhausted after last attempt in recovery path, but exception is not skippable.; nested exception is javax.persistence.PersistenceException: org.hibernate.exception.ConstraintViolationException: could not execute statement
    at org.springframework.batch.core.step.item.FaultTolerantChunkProcessor$5.recover(FaultTolerantChunkProcessor.java:405) ~[spring-batch-core-3.0.8.RELEASE.jar:3.0.8.RELEASE]
    at org.springframework.retry.support.RetryTemplate.handleRetryExhausted(RetryTemplate.java:512) ~[spring-retry-1.2.1.RELEASE.jar:na]
    at org.springframework.retry.support.RetryTemplate.doExecute(RetryTemplate.java:351) ~[spring-retry-1.2.1.RELEASE.jar:na]
    at org.springframework.retry.support.RetryTemplate.execute(RetryTemplate.java:211) ~[spring-retry-1.2.1.RELEASE.jar:na]

Answer 1

You need to make your step fault tolerant for specific exceptions.

@Bean
public Step cityStep1(ItemWriter<City> writer) {
    return stepBuilderFactory.get("cityStep1")
                .<City,City>chunk(10)
                .reader(cityReader())
                .processor(cityProcessor())
                .writer(writer)
                .faultTolerant()
                .skip(YourException.class)
                .noRetry(YourException.class)
                .noRollback(YourException.class)
                .skipLimit(10)
                .build();
}

You haven't listed your writer or exception that you received so you can put that exception in place of YourException.

noRetry , noRollBack have been put to alter default Spring Batch behavior in case of skipping as spring batch roll backs transaction for whole chunk & then reprocesses item bu item. If you are OK with that way, you can remove these parts from your step definition.