Documentation says retry limit is item-based, but it behaves as if the limit is chunk-based.

[fxpaquette]

Regarding the retry() and retryLimit() method that can be added to a faultTolerantStepBuilder.
Example:

@Bean
public Step step1(JobRepository jobRepository, PlatformTransactionManager transactionManager) {
	return new StepBuilder("step1", jobRepository)
				.<String, String>chunk(2, transactionManager)
				.reader(itemReader())
				.writer(itemWriter())
				.faultTolerant()
				.retryLimit(3)
				.retry(Exception.class)
				.build();
}

The official documentation here specifies that

The Step allows a limit for the number of times an individual item can be retried

First, the retry limit is not actually the number of retries but rather the maximum number of failed tries, since a limit of 1 one will yield no retries.
Second, in the example above, imagine the following scenario (notice the chunk size is 2 and the retry limit is 3):
An error is thrown on the two first tries for item A.
On the third attempt, item A is written succesfully.
Then, an error is thrown for item B.
Observed result: The step fails immediately for having reached the retry limit of 3.

Is the documentation misleading or there is something I am missing here ?

[fmbenhassine]

Thank you for opening this issue. We do not exclude that this could be a bug in Spring Batch. However, we are not sure to reproduce your specific problem by piecing things together from code snippets.

If you would like us to spend some time investigating, please spend some time providing a complete yet minimal example that reproduces the problem. To help you in reporting your issue, we have prepared a project template that you can use as a starting point. Please check the Issue Reporting Guidelines for more details about this. You can also check the chunk-scanning sample here (you might need to adapt it to retry items).

Thank you for your collaboration.

[fxpaquette]

Hi, sorry for the late response. I've included a minimal example to reproduce the observed behavior.

What I am trying to highlight is the fact that the retry limit (3 in my example) is actually chunk-based, rather than item-based as the docs says here

Also, a retry limit of n yields only n-1 retries.

Here is the output of my spring-batch-mcve.zip example:

[main] INFO org.springframework.batch.core.configuration.annotation.BatchRegistrar - Finished Spring Batch infrastructure beans configuration in 18 ms.
[main] INFO org.springframework.jdbc.datasource.embedded.EmbeddedDatabaseFactory - Starting embedded database: url='jdbc:h2:mem:testdb;DB_CLOSE_DELAY=-1;DB_CLOSE_ON_EXIT=false', username='sa'
[main] INFO org.springframework.batch.core.repository.support.JobRepositoryFactoryBean - No database type set, using meta data indicating: H2
[main] INFO org.springframework.batch.core.configuration.annotation.BatchObservabilityBeanPostProcessor - No Micrometer observation registry found, defaulting to ObservationRegistry.NOOP
[main] INFO org.springframework.batch.core.configuration.annotation.BatchObservabilityBeanPostProcessor - No Micrometer observation registry found, defaulting to ObservationRegistry.NOOP
[main] INFO org.springframework.batch.core.launch.support.SimpleJobLauncher - No TaskExecutor has been set, defaulting to synchronous executor.
[main] INFO org.springframework.batch.core.launch.support.SimpleJobLauncher - Job: [SimpleJob: [name=job]] launched with the following parameters: [{}]
[main] INFO org.springframework.batch.core.job.SimpleStepHandler - Executing step: [step]
reading item = 1
reading item = 2
processing item = 1
processing item = 2
About to write chunk: [items=[1, 2], skips=[]]
About to write item: 1
Throwing exception on item 1 Total: 1 exceptions
processing item = 1
processing item = 2
About to write chunk: [items=[1, 2], skips=[]]
About to write item: 1
Throwing exception on item 1 Total: 2 exceptions
processing item = 1
processing item = 2
About to write chunk: [items=[1, 2], skips=[]]
About to write item: 1
writing item = 1
About to write item: 2
Throwing exception on item 2 Total: 3 exceptions
processing item = 1
[main] ERROR org.springframework.batch.core.step.AbstractStep - Encountered an error executing step step in job job
org.springframework.retry.ExhaustedRetryException: Retry exhausted after last attempt in recovery path, but exception is not skippable. ...
FAILED