How might one get access to the JOB_EXECUTION_ID in onWriteError?

[tvaughan77]

Hi,

I have an "public class ErrorClassifyingStepListener extends StepListenerSupport<Long, Long>" I use on all my steps to map Exceptions to different Enums that I can write to an errors table in the database (our db error schema has an "error_type" column with enum values like BAD_PHONE, BAD_MSG, etc).

I'd like to keep track of which JOB_EXECUTION_ID the thread was running when I write the error to my error table, but I don't see an obvious way to get access to that information from within a StepListenerSupport child.

Any thoughts?

Thanks in advance,
Tom

[tvaughan77]

This isn't as nice or as elegant as I'd want it to be, but to get access to the job execution ID so that I might link up that ID with an error that was encountered during a step in that job's execution, I did the following:

• wrote an error row to my DB in onWriteError
• Saved off the ID of the error_row I just wrote...stored that ID in a ThreadLocal ArrayList in my listener
• In the afterStep() method (which does have access to the job execution object), I ran through the accumulated error rows and updated them with the job_execution_id

Here's the code, in case my description doesn't make sense. Not guaranteeing this is bug proof, as I haven't stressed it or reviewed it much yet. It seems to work on first blush, though:

public class AlertErrorClassifyingStepListener extends StepListenerSupport<Long, Long> {

    private CustomerAlertInstanceErrorDAO customerAlertInstanceErrorDAO;
    protected final Log log = LogFactory.getLog(this.getClass());

    /**
     * <p>Using a ThreadLocal array list here because this StepListener is a singleton shared by multiple running Alert Batch
     * Jobs in multiple running threads.  For now, each job is single-threaded.  Thus, any error we detect in the
     * onWriteError() method can be added to this thread local list so that when the step is complete we can update the
     * database in the afterStep() method to let us know what job execution ID the error happened in.</p>
     *
     * <p>We want to tie step errors with job execution IDs for display and management purposes.  Note that the Long values in
     * this array list are the customer_alert_instance_error.id fields, and <strong>not</strong>
     * the customer_alert_instance_error.customer_alert_instance_id fields.</p>
     *
     * <p>This data is garbage collected when the thread running the current job dies.</p>
     */
    private ThreadLocal<ArrayList<Long>> alertErrorThreadLocalList = new ThreadLocal<ArrayList<Long>>() {
        @Override
        protected ArrayList<Long> initialValue() {
            return new ArrayList<Long>();
        }
    };


    /**
     * <p>Update our  customer alert instance error data store with the currently running job's execution ID for
     * every error our onWriteError() method saved off to the thread-local alertErrorThreadLocalList array</p>
     * @see org.springframework.batch.core.StepExecutionListener#afterStep(org.springframework.batch.core.StepExecution)
     */
    @Override
    public ExitStatus afterStep(StepExecution stepExecution) {
        Long jobExecutionId = stepExecution.getJobExecutionId();
        for(Long errorId : alertErrorThreadLocalList.get()) {
            customerAlertInstanceErrorDAO.updateErrorWithJobExecution(errorId, jobExecutionId);
        }

        debug(log, "in afterStep for jobExecution Id %d. New errors in the customer_alert_instance table written during " +
                "this step are %s", jobExecutionId, StringUtils.join(alertErrorThreadLocalList.get(), " "));

        return super.afterStep(stepExecution);
    }

    @Override
    public ExitStatus onErrorInStep(StepExecution stepExecution, Throwable e) {
        return super.onErrorInStep(stepExecution, e);
    }

    /**
     * This is run within the transaction of the failed alert job, which will be rolled back.
     * So run this method in a new transaction.
     * See http://static.springframework.org/spring-batch/spring-batch-docs/reference/html-single/index.html#d0e4511
     * @see org.springframework.batch.core.ItemWriteListener#onWriteError(java.lang.Exception, java.lang.Object)
     */
    @Override
    @Transactional(propagation = REQUIRES_NEW)
    public void onWriteError(Exception ex, List<? extends Long> items) {
        CustomerAlertInstanceError.SkipReason skipReason = translateException(ex);
        debug(log, "Requesting alertErrorDAO logging of exception of type %s", skipReason.name());

        Long caiErrorId = customerAlertInstanceErrorDAO.logError(items.get(0), skipReason, ex);
        this.alertErrorThreadLocalList.get().add(caiErrorId);
    }

    private CustomerAlertInstanceError.SkipReason translateException(final Exception ex) {
        // ...does stuff
    }

    @Autowired
    public void setCustomerAlertInstanceErrorDAO(CustomerAlertInstanceErrorDAO customerAlertInstanceErrorDAO) {
        this.customerAlertInstanceErrorDAO = customerAlertInstanceErrorDAO;
    }
}