Java 手动更改 Spring Batch 元数据表是一个坏主意吗？
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Is it a bad idea to change the Spring Batch Meta-Data tables manually?
提问by songyuanyao
Background
背景
I'm using Spring Batch 2.1.8, and run jobs by CommandLineJobRunner. Such as:
我正在使用 Spring Batch 2.1.8，并通过CommandLineJobRunner. 如：
java org.springframework.batch.core.launch.support.CommandLineJobRunner classpath:launchContext.xml theJobId
Problem
问题
At some condition such as a server crash, running job could be interrupted.
But the interrupted job left a STARTEDstatus in the Spring Batch Meta-Data tables, and can't be run again.
在某些情况下，例如服务器崩溃，正在运行的作业可能会中断。但是中断的作业STARTED在 Spring Batch Meta-Data 表中留下了状态，并且无法再次运行。
org.springframework.batch.core.repository.JobExecutionAlreadyRunningException: A job execution for this job is already running
I can think of two solutions:
我可以想到两种解决方案：
Solution1
解决方案1
Add a new job parameter and change it everytime to make it a "new" job for Spring Batch. Such as:
添加一个新的作业参数并每次更改它以使其成为 Spring Batch 的“新”作业。如：
java org.springframework.batch.core.launch.support.CommandLineJobRunner classpath:launchContext.xml theJobId times=0
And when need to rerun it, do clear all corresponding output data, count up timesonce, and then rerun the job.
当需要重新运行时，清除所有相应的输出数据，计数times一次，然后重新运行作业。
Solution2
解决方案2
Change the Spring Batch Meta-Data tables manually.
手动更改 Spring Batch 元数据表。
To update the status to make the job restartable. Such as:
更新状态以使作业可重新启动。如：
UPDATE BATCH_JOB_EXECUTION SET END_TIME = SYSTIMESTAMP, STATUS = 'FAILED', EXIT_CODE = 'FAILOVER' WHERE JOB_EXECUTION_ID =
(SELECT MAX(JOB_EXECUTION_ID) FROM BATCH_JOB_EXECUTION WHERE JOB_INSTANCE_ID =
(SELECT MAX(JOB_INSTANCE_ID) FROM BATCH_JOB_INSTANCE WHERE JOB_NAME = 'XXX'));
I've tried it and it seems works well.
我试过了，似乎效果很好。
Question
题
Is Solution2 a bad idea? Are there any traps?
解决方案 2 是个坏主意吗？有陷阱吗？
Thanks in advance. And any other solutions are appreciated.
提前致谢。任何其他解决方案都值得赞赏。
采纳答案by Michael Minella
Solution 2 is the accepted approach right now. The API does not provide a way to fix this scenario. There have been requests in the past for the framework to clean up automatically, but 99% of the time, a human decision is needed to determine if cleanup is truly required.
解决方案 2 是目前公认的方法。API 不提供修复这种情况的方法。过去曾有人要求框架自动清理，但在 99% 的情况下，需要人工决定来确定是否确实需要清理。
My only note for option 2 would be to check the BATCH_STEP_EXECUTION table as well to see what state the last executed step was left in.
我对选项 2 的唯一说明是还要检查 BATCH_STEP_EXECUTION 表，以查看最后执行的步骤处于什么状态。
回答by Steef
I created a specific spring bean for this which is triggered on a container refresh (which happens on app (re)start too).
我为此创建了一个特定的 spring bean，它在容器刷新时触发（这也发生在应用程序（重新）启动时）。
It searches for 'running' jobs, marks them 'FAILED' and restarts them.
它搜索“正在运行”的作业，将它们标记为“失败”并重新启动它们。
import java.util.Date;
import java.util.List;
import java.util.Set;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.batch.core.BatchStatus;
import org.springframework.batch.core.JobExecution;
import org.springframework.batch.core.explore.JobExplorer;
import org.springframework.batch.core.launch.JobOperator;
import org.springframework.batch.core.repository.JobRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationListener;
import org.springframework.context.event.ContextRefreshedEvent;
import org.springframework.stereotype.Component;
@Component
public class BatchJobRestarter implements ApplicationListener<ContextRefreshedEvent> {
private static final Logger LOGGER = LoggerFactory.getLogger(BatchJobRestarter.class);
@Autowired
private JobExplorer jobExplorer;
@Autowired
JobRepository jobRepository;
@Autowired
JobOperator jobOperator;
@Override
public void onApplicationEvent(ContextRefreshedEvent contextRefreshedEvent) {
LOGGER.info("Container restart: restarting 'running' batch jobs");
List<String> jobs = jobExplorer.getJobNames();
for (String job : jobs) {
Set<JobExecution> runningJobs = jobExplorer.findRunningJobExecutions(job);
for (JobExecution runningJob : runningJobs) {
try {
LOGGER.info("Restarting job {} with parameters {}", runningJob.getJobInstance().getJobName(), runningJob.getJobParameters().toString());
runningJob.setStatus(BatchStatus.FAILED);
runningJob.setEndTime(new Date());
jobRepository.update(runningJob);
jobOperator.restart(runningJob.getId());
} catch (Exception e) {
LOGGER.error(e.getMessage(), e);
}
}
}
}
}
Steef
斯蒂夫
