How to configure graceful shutdown using DelegatingSecurityContextScheduledExecutorService with Spring

Question

I'm trying to use the new options to do graceful shutdown with spring introduced in version 2.3, but I'm struggling to make my scheduled task to behave the same way.

As I need a valid user in the context during scheduled tasks execution, I am using DelegatingSecurityContextScheduledExecutorService to achieve this goal.

Here is a sample of my implementation of SchedulingConfigurer:

@Configuration
@EnableScheduling
public class ContextSchedulingConfiguration implements SchedulingConfigurer {

    @Override
    public void configureTasks(ScheduledTaskRegistrar taskRegistrar) {
        taskRegistrar.setScheduler(taskExecutor());
    }

    @Bean
    public TaskSchedulerCustomizer taskSchedulerCustomizer() {
        return taskScheduler -> {
            taskScheduler.setAwaitTerminationSeconds(120);
            taskScheduler.setWaitForTasksToCompleteOnShutdown(true);
            taskScheduler.setPoolSize(2);
        };
    }

    @Bean
    public Executor taskExecutor() {
        ThreadPoolTaskScheduler threadPool = new ThreadPoolTaskScheduler();
        taskSchedulerCustomizer().customize(threadPool);
        threadPool.initialize();
        threadPool.setThreadNamePrefix("XXXXXXXXX");

        SecurityContext schedulerContext = createSchedulerSecurityContext();
        return new DelegatingSecurityContextScheduledExecutorService(threadPool.getScheduledExecutor(), schedulerContext);

    }

    private SecurityContext createSchedulerSecurityContext() {
        //This is just an example, the actual code makes several changes to the context.
        return SecurityContextHolder.createEmptyContext();
    }

    @Scheduled(initialDelay = 5000, fixedDelay = 15000)
    public void run() throws InterruptedException {
        System.out.println("Started at: " + LocalDateTime.now().toString());
        long until = System.currentTimeMillis() + TimeUnit.SECONDS.toMillis(30);
        while (System.currentTimeMillis() < until) {}
        System.out.println("Ended at: " + LocalDateTime.now().toString());
    }
}

But when I send a termination signal while the sheduled task is running, the application does not wait for the task.

If in my bean taskExecutor I replace the last two lines, returning the ThreadPoolTaskScheduler without a context, everything work as expected. It only doesn't work when I return the DelegatingSecurityContextScheduledExecutorService.

How can I set the context for the taskExecutor and at the same time configure to wait for tasks to complete on shutdown?

I alredy tried several variations of this code, using another implementations of the interfaces TaskScheduler and TaskExecutor, but without success.

Your code isn't clear do you want a scheduler or an executor? Also do you really need a hardcoded `SecurityContext` or propagate the existing one to the new thread? Also your code looks convulted. Nonentheless you should make both of them beans currently that isn't the case so the delegating one isn't closed. — M. Deinum, Aug 11 '20 at 04:54

score 4 · Accepted Answer · answered Aug 11 '20 at 05:06

For starters cleanup your code and use the proper return types in the bean methods (be specific) and expose both as beans (marking one as @Primary!).

@Configuration
@EnableScheduling
public class ContextSchedulingConfiguration implements SchedulingConfigurer {

    @Override
    public void configureTasks(ScheduledTaskRegistrar taskRegistrar) {
        taskRegistrar.setScheduler(securitytaskScheduler());
    }

    @Bean
    public ThreadPoolTaskScheduler taskScheduler() {
        ThreadPoolTaskScheduler taskScheduler= new ThreadPoolTaskScheduler();
        taskScheduler.setAwaitTerminationSeconds(120);
        taskScheduler.setWaitForTasksToCompleteOnShutdown(true);
        taskScheduler.setPoolSize(2);
        taskScheduler.setThreadNamePrefix("XXXXXXXXX");
        return taskScheduler;
    }
    
    @Bean
    @Primary
    public DelegatingSecurityContextScheduledExecutorService securitytaskScheduler() {
        SecurityContext schedulerContext = createSchedulerSecurityContext();
        return new DelegatingSecurityContextScheduledExecutorService(taskScheduler().getScheduledExecutor(), schedulerContext);

   }

    private SecurityContext createSchedulerSecurityContext() {
        //This is just an example, the actual code makes several changes to the context.
        return SecurityContextHolder.createEmptyContext();
    }

    @Scheduled(initialDelay = 5000, fixedDelay = 15000)
    public void run() throws InterruptedException {
        System.out.println("Started at: " + LocalDateTime.now().toString());
        long until = System.currentTimeMillis() + TimeUnit.SECONDS.toMillis(30);
        while (System.currentTimeMillis() < until) {}
        System.out.println("Ended at: " + LocalDateTime.now().toString());
    }
}

Important is to be as specific in your return types as possible. Configuration classes are detected early on and the return types are checked to determine the callbacks to be made. Now ThradPoolTaskScheduler is a DisposableBean an Executor is not and will not receive callbacks as such!.

Exposing `ThreadPoolTaskScheduler ` as a bean did the trick. Probably because of the `DisposableBean` behavior that you mentioned. Thank you very much @m-deinum for the tips, I'll consider them from now on. — Petter, Aug 11 '20 at 13:45

How to configure graceful shutdown using DelegatingSecurityContextScheduledExecutorService with Spring

1 Answers1

Linked