I'm trying to copy Spring context to Runnable/Callable tasks for a special case. I want other threads to run as they run before.
I've read this How to enable request scope in async task executor
and implemented a custom ThreadPoolTaskExecutor + decorator.
#Configuration
public class ContextCopyConfig {
private Integer connectionsLimit=10;
#Bean(name = "contextExecutor")
public Executor contextExecutor() {
ThreadPoolTaskExecutor poolExecutor = new ThreadPoolTaskExecutor();
poolExecutor.setTaskDecorator(new ContextCopyingDecorator());
poolExecutor.setMaxPoolSize(connectionsLimit);
poolExecutor.setCorePoolSize(connectionsLimit);
poolExecutor.initialize();
return poolExecutor;
}
}
I was planning to use this executor as follows:
#Autowired
#Qualifier(value = "contextExecutor")
private Executor contextExecutor;
public void parallelHere() throws IOException, InterruptedException, ExecutionException {
Collection<Callable<Pair<String, OutputStream>>> tasks = new ArrayList<>(); //some tasks
//ExecutorService executor = Executors.newFixedThreadPool(connectionsLimit);
List<Future<Pair<String, OutputStream>>> results = ((ThreadPoolTaskExecutor) contextExecutor).getThreadPoolExecutor().invokeAll(tasks);
((ThreadPoolTaskExecutor) contextExecutor).getThreadPoolExecutor().shutdown(); //always reclaim resources
}
However, contextExecutor is always invoked (in any thread!).
How can I fix it?
This post:
How to create additional TaskExecutor beside TaskExecutionAutoConfiguration?
describes the issue. Springboot creates a default Executor only if user did not create a custom one.
In SpringBoot 2+ you have to use
#AutoConfigureAfter(TaskExecutionAutoConfiguration.class)
on your custom configuration.
In previous Spring versions however, no TaskExecutionAutoConfiguration exists and Executor is created by a factory. Using lines below, you can create the exect copy of default executor, created by Spring.
#Primary
#Bean
//see package org.springframework.aop.interceptor.AsyncExecutionInterceptor
public Executor getDefaultExecutor(){
// Executor defaultExecutor = super.getDefaultExecutor(beanFactory);
// return (defaultExecutor != null ? defaultExecutor : new SimpleAsyncTaskExecutor());
return new SimpleAsyncTaskExecutor();
}
KafkaProperties java doc:
/**
* What to do when there is no initial offset in Kafka or if the current offset
* does not exist any more on the server.
*/
private String autoOffsetReset;
I have hello world appllication which contains application.properties
spring.kafka.consumer.group-id=foo
spring.kafka.consumer.auto-offset-reset=latest
At this case #KafkaListener method is invoked for all entries. But expected result was that #KafkaListener method is invoked only for latest 3 options I send. I tried to use another option:
spring.kafka.consumer.auto-offset-reset=earlisest
But behaviour the same.
Can you explain this stuff?
P.S.
code sample:
#SpringBootApplication
public class Application implements CommandLineRunner {
public static Logger logger = LoggerFactory.getLogger(Application.class);
public static void main(String[] args) {
SpringApplication.run(Application.class, args).close();
}
#Autowired
private KafkaTemplate<String, String> template;
private final CountDownLatch latch = new CountDownLatch(3);
#Override
public void run(String... args) throws Exception {
this.template.send("spring_kafka_topic", "foo1");
this.template.send("spring_kafka_topic", "foo2");
this.template.send("spring_kafka_topic", "foo3");
latch.await(60, TimeUnit.SECONDS);
logger.info("All received");
}
#KafkaListener(topics = "spring_kafka_topic")
public void listen(ConsumerRecord<?, ?> cr) throws Exception {
logger.info(cr.toString());
latch.countDown();
}
}
Update:
Behaviour doesn't depends on
spring.kafka.consumer.auto-offset-reset
it is only depends on spring.kafka.consumer.auto-offset-reset=earliest
spring.kafka.consumer.enable-auto-commit
if I set spring.kafka.consumer.enable-auto-commit=false - I see all records.
if I set spring.kafka.consumer.enable-auto-commit=true - I see only 3 last records.
Please clarify menaning of spring.kafka.consumer.auto-offset-reset property
The KafkaProperties in Spring Boot does this:
public Map<String, Object> buildProperties() {
Map<String, Object> properties = new HashMap<String, Object>();
if (this.autoCommitInterval != null) {
properties.put(ConsumerConfig.AUTO_COMMIT_INTERVAL_MS_CONFIG,
this.autoCommitInterval);
}
if (this.autoOffsetReset != null) {
properties.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG,
this.autoOffsetReset);
}
This buildProperties() is used from the buildConsumerProperties() which, in turn in the:
#Bean
#ConditionalOnMissingBean(ConsumerFactory.class)
public ConsumerFactory<?, ?> kafkaConsumerFactory() {
return new DefaultKafkaConsumerFactory<Object, Object>(
this.properties.buildConsumerProperties());
}
So, if you use your own ConsumerFactory bean definition be sure to reuse those KafkaProperties: https://docs.spring.io/spring-boot/docs/1.5.7.RELEASE/reference/htmlsingle/#boot-features-kafka-extra-props
UPDATE
OK. I see what's going on.
Try to add this property:
spring.kafka.consumer.enable-auto-commit=false
This way we won't have async auto-commits based on some commit interval.
The logic in our application is based on the exit fact after the latch.await(60, TimeUnit.SECONDS);. When we get 3 expected records we exit. This way the async auto-commit from the consumer might not happen yet. So, the next time you run the application the consumer polls data from the uncommited offset.
When we turn off auto-commit, we have an AckMode.BATCH, which is performed synchronously and we have an ability to see really latest recodrs in the topic for this foo consumer group.
Can anybody tell my is there a way of using the Spring Framework's #Async annotation without blocking / waiting on the result? Here is some code to clarify my question:
#Service
public class AsyncServiceA {
#Autowired
private AsyncServiceB asyncServiceB;
#Async
public CompletableFuture<String> a() {
ThreadUtil.silentSleep(1000);
return asyncServiceB.b();
}
}
#Service
public class AsyncServiceB {
#Async
public CompletableFuture<String> b() {
ThreadUtil.silentSleep(1000);
return CompletableFuture.completedFuture("Yeah, I come from another thread.");
}
}
and the configuration:
#SpringBootApplication
#EnableAsync
public class Application implements AsyncConfigurer {
private static final Log LOG = LogFactory.getLog(Application.class);
private static final int THREAD_POOL_SIZE = 1;
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
#Bean
public CommandLineRunner commandLineRunner(ApplicationContext ctx) {
return args -> {
final AsyncServiceA bean = ctx.getBean(AsyncServiceA.class);
bean.a().whenComplete(LOG::info);
};
}
#Override
#Bean(destroyMethod = "shutdown")
public ThreadPoolTaskExecutor getAsyncExecutor() {
final ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(THREAD_POOL_SIZE);
executor.setMaxPoolSize(THREAD_POOL_SIZE);
executor.initialize();
return executor;
}
#Override
public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
// omitted
}
}
When I run the application the executor goes through calling AsyncServiceA.a() and leaves, but it still holds the thread from the pool waiting on the CompletableFuture.get() method. Since there is just a single thread in the pool the AsyncServiceB.b() cannot be executed. What I'm expecting is that thread to be returned to the pool after it executes the AsyncServiceA.a() and then be available to execute the AsyncServiceB.b().
Is there a way to do that?
Note 1: I've tried with ListenableFuture also but the result is the same.
Note 2: I've successfully did it manually (without the #Async) by giving the executor to each method like so:
AsyncServiceA
public CompletableFuture<String> manualA(Executor executor) {
return CompletableFuture.runAsync(() -> {
LOG.info("manualA() working...");
ThreadUtil.silentSleep(1000);
}, executor)
.thenCompose(x -> asyncServiceB.manualB(executor));
}
AsyncServiceB
public CompletableFuture<String> manualB(Executor executor) {
return CompletableFuture.runAsync(() -> {
LOG.info("manualB() working...");
ThreadUtil.silentSleep(1000);
}, executor)
.thenCompose(x -> CompletableFuture
.supplyAsync(() -> "Yeah, I come from another thread.", executor));
}
Here is the ThreadUtil if someone was wondering.
public class ThreadUtil {
public static void silentSleep(long millis) {
try {
Thread.sleep(millis);
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
}
}
Update: Added issue for non-blocking Async annotation https://jira.spring.io/browse/SPR-15401
The #Async support has been part of Spring since Spring 3.0 which was way before the existence of Java8 (or 7 for that matter). Although support has been added for CompletableFutures in later versions it still is to be used for simple async execution of a method call. (The initial implementation reflects/shows the call).
For composing callbacks and operate non blocking the async support was never designed or intended to.
For non blocking support you would want to wait for Spring 5 with its reactive/non-blocking core, next to that you can always submit a ticket for non-blocking support in the async support.
I've responded on the ticket https://jira.spring.io/browse/SPR-15401 but I'll respond here as well to qualify the response by M. Deinum.
#Async by virtue of how it works (decorating the method call via AOP) can only do one thing, which is to turn the entire method from sync to async. That means the method has to be sync, not a mix of sync and async.
So ServiceA which does some sleeping and then delegates to the async ServiceB would have to wrap the sleeping part in some #Async ServiceC and then compose on ServiceB and C. That way ServiceA becomes async and does not need to have the #Async annotation itself..
This is my scenario:
My app has Mongo Auditing enabled, with a custom AuditorAware which gets the current user from the SecurityContext. This works well with synchronous methods, and the current auditor is successfully saved, but I can't make it work properly with #Async methods.
I have an async method (CompletableFuture) that makes some updates on my Mongo Database. When the AuditorAware.getCurrentAuditor() is called, no authentication info exists, and I can't get the current auditor (SecurityContextHolder.getContext().getAuthentication() returns null).
#Override
public User getCurrentAuditor() {
Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
if (authentication == null || !authentication.isAuthenticated()
|| authentication instanceof AnonymousAuthenticationToken) {
log.error("Not authenticated");
return null;
}
[...]
}
I'm using a DelegatingSecurityContextAsyncTaskExecutor:
#Configuration
#EnableAsync
public class AsyncConfig implements AsyncConfigurer {
#Override
public Executor getAsyncExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(20);
executor.setMaxPoolSize(100);
executor.setQueueCapacity(200);
executor.initialize();
return new DelegatingSecurityContextAsyncTaskExecutor(executor);
}
#Override
public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
return new ItacaExceptionHandler();
}
}
How can I make it work properly?
Spring security context is always bound to Threadlocal.
Probabably you may to additionally set MODE_INHERITABLETHREADLOCAL for the security context.
#Bean
public MethodInvokingFactoryBean methodInvokingFactoryBean() {
MethodInvokingFactoryBean methodInvokingFactoryBean = new MethodInvokingFactoryBean();
methodInvokingFactoryBean.setTargetClass(SecurityContextHolder.class);
methodInvokingFactoryBean.setTargetMethod("setStrategyName");
methodInvokingFactoryBean.setArguments(new String[]{SecurityContextHolder.MODE_INHERITABLETHREADLOCAL});
return methodInvokingFactoryBean;
}
http://www.ogrigas.eu/spring/2010/04/inherit-spring-security-context-in-child-threads
How to set up Spring Security SecurityContextHolder strategy?
Following the comments on kuhajeyan's answer, it appears you are not properly using CompletableFuture with Spring #Async.
If you launch your tasks by using e.g. CompletableFuture.supplyAsync(Supplier), they will be executed by the common ForkJoinPool and not the one you have configured for #Async. You could use the overloads that take an Executor as argument, but it would not actually benefit from the advantages of #Async.
What you should do, instead, is let Spring handle the task execution, and simply return a completed CompletableFuture like this:
#Async
public CompletableFuture<String> someMethod() {
// do some computation, but return a completed future
return CompletableFuture.completedFuture("Hello World!");
}
Spring will then execute your method asynchronously in the configured executor while immediately return a CompletableFuture which will be completed when your method returns.
If you are using Spring 4.2 or above, this is supported out of the box. Otherwise there is a bit of implementation required, but that would be for another question.
In my app I have some async web services. Server accept request, return OK response and start processing request with AsyncTaskExecutor. My question is how to enable request scope here because in this processing I need to get class which is annotated by:
#Scope(value = WebApplicationContext.SCOPE_REQUEST, proxyMode = ScopedProxyMode.TARGET_CLASS)
Now I get exception:
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scopedTarget.requestContextImpl': Scope 'request' is not active for the current thread; consider defining a scoped proxy for this bean if you intend to refer to it from a singleton; nested exception is java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet/DispatcherPortlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.
because it runs in SimpleAsyncTaskExecutor and not in DispatcherServlet
my async processing of request
taskExecutor.execute(new Runnable() {
#Override
public void run() {
asyncRequest(request);
}
});
where taskExecutor is:
<bean id="taskExecutor" class="org.springframework.core.task.SimpleAsyncTaskExecutor" />
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();
}
}
The easiest way is to use a task decorator like this:
static class ContextCopyingDecorator implements TaskDecorator {
#Nonnull
#Override
public Runnable decorate(#Nonnull Runnable runnable) {
RequestAttributes context =
RequestContextHolder.currentRequestAttributes();
Map<String, String> contextMap = MDC.getCopyOfContextMap();
return () -> {
try {
RequestContextHolder.setRequestAttributes(context);
MDC.setContextMap(contextMap);
runnable.run();
} finally {
MDC.clear();
RequestContextHolder.resetRequestAttributes();
}
};
}
}
To add this decorator to the task executor, all you need is to add it in the configuration routine:
#Override
#Bean
public Executor getAsyncExecutor() {
ThreadPoolTaskExecutor poolExecutor = new ThreadPoolTaskExecutor();
poolExecutor.setTaskDecorator(new ContextCopyingDecorator());
poolExecutor.initialize();
return poolExecutor;
}
There is no need for an additional holder or a custom thread-pool task executor.
A small update for 2021: Using current versions of Spring Boot, the mere existence of a bean of type TaskDecorator will suffice. Upon creating the context, the task decorator will be used to decorate the executors that Spring Boot creates.
The solutions mentioned before were not working for me.
The reason why the solution not working is, as mentioned in #Thilak's post, as soon as the original parent thread committed response to the client, the request objects may be garbage collected.
But with some tweak to the solution provided by #Armadillo I was able to get it working. I am using spring boot 2.2
Here is what I followed.
Create a custom TaskPoolExecutor that stores(after cloning) scoped
information with the tasks.
Create a special Callable (or Runnable)
that uses the cloned information to set the current context values
and clear the context for the async thread.
Executor (Same as in #Armadillo's post):
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 final RequestAttributes requestAttributes;
public ContextAwareCallable(Callable<T> task, RequestAttributes requestAttributes) {
this.task = task;
this.requestAttributes = cloneRequestAttributes(requestAttributes);
}
#Override
public T call() throws Exception {
try {
RequestContextHolder.setRequestAttributes(requestAttributes);
return task.call();
} finally {
RequestContextHolder.resetRequestAttributes();
}
}
private RequestAttributes cloneRequestAttributes(RequestAttributes requestAttributes){
RequestAttributes clonedRequestAttribute = null;
try{
clonedRequestAttribute = new ServletRequestAttributes(((ServletRequestAttributes) requestAttributes).getRequest(), ((ServletRequestAttributes) requestAttributes).getResponse());
if(requestAttributes.getAttributeNames(RequestAttributes.SCOPE_REQUEST).length>0){
for(String name: requestAttributes.getAttributeNames(RequestAttributes.SCOPE_REQUEST)){
clonedRequestAttribute.setAttribute(name,requestAttributes.getAttribute(name,RequestAttributes.SCOPE_REQUEST),RequestAttributes.SCOPE_REQUEST);
}
}
if(requestAttributes.getAttributeNames(RequestAttributes.SCOPE_SESSION).length>0){
for(String name: requestAttributes.getAttributeNames(RequestAttributes.SCOPE_SESSION)){
clonedRequestAttribute.setAttribute(name,requestAttributes.getAttribute(name,RequestAttributes.SCOPE_SESSION),RequestAttributes.SCOPE_SESSION);
}
}
if(requestAttributes.getAttributeNames(RequestAttributes.SCOPE_GLOBAL_SESSION).length>0){
for(String name: requestAttributes.getAttributeNames(RequestAttributes.SCOPE_GLOBAL_SESSION)){
clonedRequestAttribute.setAttribute(name,requestAttributes.getAttribute(name,RequestAttributes.SCOPE_GLOBAL_SESSION),RequestAttributes.SCOPE_GLOBAL_SESSION);
}
}
return clonedRequestAttribute;
}catch(Exception e){
return requestAttributes;
}
}
}
The change I made is to introduce cloneRequestAttributes() to copy and set the RequestAttribute, so that the values remain available even after the original parent thread commits response to the client.
Configuration:
Since there are other async configuration and I didn't want the behavior to be applicable in other async executors I've created its own task executor configuration.
#Configuration
#EnableAsync
public class TaskExecutorConfig {
#Bean(name = "contextAwareTaskExecutor")
public TaskExecutor getContextAwareTaskExecutor() {
ContextAwarePoolExecutor taskExecutor = new ConAwarePoolExecutor();
taskExecutor.setMaxPoolSize(20);
taskExecutor.setCorePoolSize(5);
taskExecutor.setQueueCapacity(100);
taskExecutor.setThreadNamePrefix("ContextAwareExecutor-");
return taskExecutor;
}
}
And finally on the async method, I use the executor name.
#Async("contextAwareTaskExecutor")
public void asyncMethod() {
}
Alternate Solution:
We ended up in this trouble by trying to reuse an existing component class. Though the solution made it look like it is convenient. Its much less hassle (cloning objects and reserving thread pool) if we could have referred the relevant request scoped values as method parameters. In our case, we are planning to refactor the code in such a way that the component class which is using the request scoped bean, and being reused from the async method, to accept the values as method parameters. Request scoped bean is removed from the reusable component and moved to the component class which invokes its method.
To put what I just described it in code:
Our current state is :
#Async("contextAwareTaskExecutor")
public void asyncMethod() {
reUsableCompoment.executeLogic() //This component uses the request scoped bean.
}
Refactored code:
#Async("taskExecutor")
public void asyncMethod(Object requestObject) {
reUsableCompoment.executeLogic(requestObject); //Request scoped bean is removed from the component and moved to the component class which invokes it menthod.
}
There is no way to get a request scoped object in an child async thread, since the original parent request processing thread may have already committed the response to the client and all the request objects are destroyed. One way to handle such scenarios is to use custom scope, like SimpleThreadScope.
one problem with SimpleThreadScope is that the child threads will not inherit parents scope variables, because it uses simple ThreadLocal internally. To overcome that implement a custom scope which is exactly similar to SimpleThreadScope but uses InheritableThreadLocal internally. For more info reg this
Spring MVC: How to use a request-scoped bean inside a spawned thread?
None of the above Solution works for me because in my case the parent thread responded for request back to the client and the request scoped object can't be referred in any worker threads.
I just made a work around to make above things work. I am using Spring Boot 2.2 and using customTaskExecutor with ContextAwareCallable just specified above.
Async Configuration:
#Bean(name = "cachedThreadPoolExecutor")
public Executor cachedThreadPoolExecutor() {
ThreadPoolTaskExecutor threadPoolTaskExecutor = new ContextAwarePoolExecutor();
threadPoolTaskExecutor.setCorePoolSize(corePoolSize);
threadPoolTaskExecutor.setMaxPoolSize(maxPoolSize);
threadPoolTaskExecutor.setQueueCapacity(queueCapacity);
threadPoolTaskExecutor.setAllowCoreThreadTimeOut(true);
threadPoolTaskExecutor.setThreadNamePrefix("ThreadName-");
threadPoolTaskExecutor.initialize();
return threadPoolTaskExecutor;
}
ContextAwarePoolExecutor:
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()));
}
}
Created Custom Context Aware Callable:
public class ContextAwareCallable<T> implements Callable<T> {
private Callable<T> task;
private CustomRequestScopeAttributes customRequestScopeAttributes;
private static final String requestScopedBean =
"scopedTarget.requestScopeBeanName";
public ContextAwareCallable(Callable<T> task, RequestAttributes context) {
this.task = task;
if (context != null) {
//This is Custom class implements RequestAttributes class
this.customRequestScopeAttributes = new CustomRequestScopeAttributes();
//Add the request scoped bean to Custom class
customRequestScopeAttributes.setAttribute
(requestScopedBean,context.getAttribute(requestScopedBean,0),0);
//Set that in RequestContextHolder and set as Inheritable as true
//Inheritable is used for setting the attributes in diffrent ThreadLocal objects.
RequestContextHolder.setRequestAttributes
(customRequestScopeAttributes,true);
}
}
#Override
public T call() throws Exception {
try {
return task.call();
} finally {
customRequestScopeAttributes.removeAttribute(requestScopedBean,0);
}
}
}
Custom class:
public class CustomRequestScopeAttributes implements RequestAttributes {
private Map<String, Object> requestAttributeMap = new HashMap<>();
#Override
public Object getAttribute(String name, int scope) {
if(scope== RequestAttributes.SCOPE_REQUEST) {
return this.requestAttributeMap.get(name);
}
return null;
}
#Override
public void setAttribute(String name, Object value, int scope) {
if(scope== RequestAttributes.SCOPE_REQUEST){
this.requestAttributeMap.put(name, value);
}
}
#Override
public void removeAttribute(String name, int scope) {
if(scope== RequestAttributes.SCOPE_REQUEST) {
this.requestAttributeMap.remove(name);
}
}
#Override
public String[] getAttributeNames(int scope) {
if(scope== RequestAttributes.SCOPE_REQUEST) {
return this.requestAttributeMap.keySet().toArray(new String[0]);
}
return new String[0];
}
//Override all methods in the RequestAttributes Interface.
}
Finally add the Async annotation in the method needed.
#Async("cachedThreadPoolExecutor")
public void asyncMethod() {
anyService.execute() //This Service execution uses request scoped bean
}
With Spring-boot-2.0.3.REALEASE / spring-web-5.0.7, I've come up with below code working for #Async
Class that holds the ThreadLocal context.
import java.util.Map;
public class ThreadContextHolder {
private ThreadContextHolder() {}
private static final ThreadLocal<Map<String, Object>> ctx = new ThreadLocal<>();
public static Map<String, Object> getContext() {
return ctx.get();
}
public static void setContext(Map<String, Object> attrs) {
ctx.set(attrs);
}
public static void removeContext() {
ctx.remove();
}
}
Async config :
#Bean
public Executor taskExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
...
...
executor.setTaskDecorator(
runnable -> {
RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes(); // or currentRequestAttributes() if you want to fall back to JSF context.
Map<String, Object> map =
Arrays.stream(requestAttributes.getAttributeNames(0))
.collect(Collectors.toMap(r -> r, r -> requestAttributes.getAttribute(r, 0)));
return () -> {
try {
ThreadContextHolder.setContext(map);
runnable.run();
} finally {
ThreadContextHolder.removeContext();
}
};
});
executor.initialize();
return executor;
}
And from the async method :
#Async
public void asyncMethod() {
logger.info("{}", ThreadContextHolder.getContext().get("key"));
}
#Armadillo's answer motivated me to write the implementation for Runnable.
Custom implementation for TaskExecutor:
/**
* This custom ThreadPoolExecutor stores scoped/context information with the tasks.
*/
public class ContextAwareThreadPoolExecutor extends ThreadPoolTaskExecutor {
#Override
public Future<?> submit(Runnable task) {
return super.submit(new ContextAwareRunnable(task, RequestContextHolder.currentRequestAttributes()));
}
#Override
public ListenableFuture<?> submitListenable(Runnable task) {
return super.submitListenable(new ContextAwareRunnable(task, RequestContextHolder.currentRequestAttributes()));
}
}
Custom implementation for Runnable:
/**
* This custom Runnable class can use to make background threads context aware.
* It store and clear the context for the background threads.
*/
public class ContextAwareRunnable implements Runnable {
private Runnable task;
private RequestAttributes context;
public ContextAwareRunnable(Runnable task, RequestAttributes context) {
this.task = task;
// Keeps a reference to scoped/context information of parent thread.
// So original parent thread should wait for the background threads.
// Otherwise you should clone context as #Arun A's answer
this.context = context;
}
#Override
public void run() {
if (context != null) {
RequestContextHolder.setRequestAttributes(context);
}
try {
task.run();
} finally {
RequestContextHolder.resetRequestAttributes();
}
}
}
I solved this issue adding the following bean configuration
<bean class="org.springframework.beans.factory.config.CustomScopeConfigurer">
<property name="scopes">
<map>
<entry key="request">
<bean class="org.springframework.context.support.SimpleThreadScope"/>
</entry>
</map>
</property>
</bean>
Update: the above solution does not clean up any objects associated with the threads as mention in spring's documentation. This alternative works for me: https://www.springbyexample.org/examples/custom-thread-scope-module.html
#Armadillo
Worked for me, many thanks.
As for Spring Security Context, there is more out-of-box solution and it worked for me either (found here How to set up Spring Security SecurityContextHolder strategy?)
In order to use SecurityContextHolder in child threads:
#Bean
public MethodInvokingFactoryBean methodInvokingFactoryBean() {
MethodInvokingFactoryBean methodInvokingFactoryBean = new MethodInvokingFactoryBean();
methodInvokingFactoryBean.setTargetClass(SecurityContextHolder.class);
methodInvokingFactoryBean.setTargetMethod("setStrategyName");
methodInvokingFactoryBean.setArguments(new String[]{SecurityContextHolder.MODE_INHERITABLETHREADLOCAL});
return methodInvokingFactoryBean;
}
Here is a related answer for anyone who wants to use RequestScope with non blocking I/O commands in an API, as opposed to spinning up child threads that live on past the original HTTP request.
SPRING ASYNC AWAIT REQUEST SCOPE
It is possible to implement a custom scope in Spring which stores request scoped objects in the current HttpServletRequest object, so that objects can be accessed before and after 'await' statements:
Async Await Usage
HttpServletRequest based RequestScope
Full Java API Code Sample