How to Enable Request Scope in Async Task Executor

How to enable request scope in async task executor

We ran into the same problem - needed to execute code in the background using @Async, so it was unable to use any Session- or RequestScope beans. We solved it the following way:

• Create a custom TaskPoolExecutor that stores scoped information with the tasks
• Create a special Callable (or Runnable) that uses the information to set and clear the context for the background thread
• Create an override configuration to use the custom executor

Note: this will only work for Session and Request scoped beans, and not for security context (as in Spring Security). You'd have to use another method to set the security context if that is what you're after.

Note2: For brevity, only shown the Callable and submit() implementation. You can do the same for the Runnable and execute().

Here is the code:

Executor:

public class ContextAwarePoolExecutor extends ThreadPoolTaskExecutor {
    @Override
    public <T> Future<T> submit(Callable<T> task) {
        return super.submit(new ContextAwareCallable(task, RequestContextHolder.currentRequestAttributes()));
    }

    @Override
    public <T> ListenableFuture<T> submitListenable(Callable<T> task) {
        return super.submitListenable(new ContextAwareCallable(task, RequestContextHolder.currentRequestAttributes()));
    }
}

Callable:

public class ContextAwareCallable<T> implements Callable<T> {
    private Callable<T> task;
    private RequestAttributes context;

    public ContextAwareCallable(Callable<T> task, RequestAttributes context) {
        this.task = task;
        this.context = context;
    }

    @Override
    public T call() throws Exception {
        if (context != null) {
            RequestContextHolder.setRequestAttributes(context);
        }

        try {
            return task.call();
        } finally {
            RequestContextHolder.resetRequestAttributes();
        }
    }
}

Configuration:

@Configuration
public class ExecutorConfig extends AsyncConfigurerSupport {
    @Override
    @Bean
    public Executor getAsyncExecutor() {
        return new ContextAwarePoolExecutor();
    }
}

SimpleAsyncTaskExecutor Interceptor - Enable Request Scope in SimpleAsyncTaskExecutor

So I also tried another solution using ThreadPoolTaskExecutor.

Basically I used this solution: http://www.chrisport.ch/java/2016/10/12/java-spring-context-aware.html and switched MDC context stuff to final RequestAttributes originalContextCopy = RequestContextHolder.getRequestAttributes(); and RequestContextHolder.resetRequestAttributes();

Scope 'request' is not active for the current thread while using @Async

That is correct, an @Async thread cannot be bound to or use request scope as there is no request scope in the asynchronous execution.

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