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How To Stop Polling InboundChannelAdapter

Im polling files from 2 different directories in 1 server using RotatingServerAdvice and that´s working fine, the problem is that I can´t stop polling once time I start the inboundtest.start (). The main idea is retrive all the files in those directories, and then send inboundtest.stop (), this is the code.
#Bean
public SessionFactory<LsEntry> sftpSessionFactory() {
DefaultSftpSessionFactory factory = new DefaultSftpSessionFactory(false);
factory.setHost(host);
factory.setPort(port);
factory.setUser(user);
factory.setPassword(password);
factory.setAllowUnknownKeys(true);
//factory.setTestSession(true);
return factory;
}
#Bean
public SftpInboundFileSynchronizer sftpInboundFileSynchronizer() {
SftpInboundFileSynchronizer fileSynchronizer = new SftpInboundFileSynchronizer(sftpSessionFactory());
fileSynchronizer.setDeleteRemoteFiles(true);
fileSynchronizer.setRemoteDirectory(sftpRemoteDirectory);
fileSynchronizer.setFilter(new SftpRegexPatternFileListFilter(".*?\\.(txt|TXT?)"));
return fileSynchronizer;
}
#Bean(name = "sftpMessageSource")
#EndpointId("inboundtest")
#InboundChannelAdapter(channel = "sftpChannel",poller = #Poller("fileReadingMessageSourcePollerMetadata"), autoStartup = "false")
public MessageSource<File> sftpMessageSource() {
SftpInboundFileSynchronizingMessageSource source =
new SftpInboundFileSynchronizingMessageSource(sftpInboundFileSynchronizer());
source.setLocalDirectory(new File(sftpLocalDirectoryDownloadUpload));
source.setAutoCreateLocalDirectory(true);
source.setLocalFilter(new AcceptOnceFileListFilter<File>());
return source;
}
#Bean
public DelegatingSessionFactory<LsEntry> sessionFactory() {
Map<Object, SessionFactory<LsEntry>> factories = new LinkedHashMap<>();
factories.put("one", sftpSessionFactory());
// use the first SF as the default
return new DelegatingSessionFactory<LsEntry>(factories, factories.values().iterator().next());
}
#Bean
public RotatingServerAdvice advice() {
List<RotationPolicy.KeyDirectory> keyDirectories = new ArrayList<>();
keyDirectories.add(new RotationPolicy.KeyDirectory("one", sftpRemoteDirectory));
keyDirectories.add(new RotationPolicy.KeyDirectory("one", sftpRemoteDirectoryNonUpload));
return new RotatingServerAdvice(sessionFactory(), keyDirectories, false);
}
#Bean
MessageChannel controlChannel() {
return new DirectChannel();
}
#Bean
#ServiceActivator(inputChannel = "controlChannel")
ExpressionControlBusFactoryBean controlBus() {
return new ExpressionControlBusFactoryBean();
}
#Bean
public PollerMetadata fileReadingMessageSourcePollerMetadata() {
PollerMetadata meta = new PollerMetadata();
meta.setTrigger(new PeriodicTrigger(1000));
meta.setAdviceChain(List.of(advice()));
meta.setMaxMessagesPerPoll(1);
meta.setErrorHandler(throwable -> new IOException());
return meta;
}
Allways is waiting for a new file in one of the 2 directories, but thats no the idea, the idea is stop polling when all the files be retrived
From another class I call inbound.start() trouhg the control chanel here the code:
#Autowired
private MessageChannel controlChannel;
public void startProcessingFiles() throws InterruptedException {
controlChannel.send(new GenericMessage<>("#inboundtest.start()"));
}
I was tryong stop with this class but doesn´t works
#Component
public class StopPollingAdvice implements ReceiveMessageAdvice {
#Autowired
private MessageChannel controlChannel;
#Override
public Message<?> afterReceive(Message<?> message, Object o) {
System.out.println("There is no more files, stopping connection" + message.getPayload());
if(message == null) {
System.out.println("There is no more files, stopping connection" + message.getPayload());
Message operation = MessageBuilder.withPayload("#inboundtest.stop()").build();
controlChannel.send(operation);
}
return message;
}
}

OK. Now I see your point. The RotatingServerAdvice does move to other server only when the first is exhausted (by default, see that fair option). So, when you stop it in the advice it cannot go to other dir for fetching any more. You need to think about some other stopping solution. Something what is not tied to the advice and this afterReceive(), somewhere downstream in your flow...
Or you can provide a custom RotationPolicy (extension of StandardRotationPolicy) and in its overridden afterReceive() check for all the dirs processed and then send stop command.

Spring Integration - Async service activator for SQS messages

I am trying to implement an Integration flow for a sqs queue using a void async service activator but the handling logic is never triggered.
The message is received in the flow, succesfuly converted by my custom transformer but the async handling is never completed.
This is my configuration class:
#Configuration
public class SqsConfiguration {
/**
...
...
**/
#Bean("amazonSQSClientConfiguration")
ClientConfiguration getAmazonSQSClientConfiguration() {
ClientConfiguration clientConfiguration = new ClientConfiguration();
clientConfiguration.setConnectionTimeout(connectionTimeout);
clientConfiguration.setMaxConnections(maxConnections);
clientConfiguration.setSocketTimeout(socketTimeout);
clientConfiguration.setMaxConsecutiveRetriesBeforeThrottling(maxConsecutiveRetriesBeforeThrottling);
return clientConfiguration;
}
#Bean("amazonSQSAsync")
AmazonSQSAsync getAmazonSQSAsync() {
return AmazonSQSAsyncClientBuilder.standard()
.withClientConfiguration(getAmazonSQSClientConfiguration())
.withRegion(this.region)
.build();
}
#Bean("amazonSQSRequestListenerContainerConsumerPool")
protected ThreadPoolTaskExecutor amazonSQSRequestListenerContainerConsumerPool() {
int maxSize = (int) Math.round(concurrentHandlers * poolSizeFactor);
int queueCapacity = (int) Math.round(concurrentHandlers * poolQueueSizeFactor);
ThreadPoolTaskExecutor taskExecutor = new ThreadPoolTaskExecutor();
taskExecutor.setCorePoolSize(concurrentHandlers);
taskExecutor.setMaxPoolSize(maxSize);
taskExecutor.setKeepAliveSeconds(poolKeepAliveTimeSeconds);
taskExecutor.setQueueCapacity(queueCapacity);
taskExecutor.setThreadFactory(new NamedDaemonThreadFactory("AmazonSQSRequestHandler"));
taskExecutor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
log.info(
String.format(
"Amazon SQS request handler pool settings: {coreSize: %d, maxSize: %d, queueCapacity: %d}",
concurrentHandlers,
maxSize,
queueCapacity
)
);
return taskExecutor;
}
#Bean("sqsMessageDrivenChannelAdapter")
public MessageProducerSupport sqsMessageDrivenChannelAdapter() {
SqsMessageDrivenChannelAdapter adapter = new SqsMessageDrivenChannelAdapter(getAmazonSQSAsync(), this.queueName);
adapter.setMaxNumberOfMessages(this.maxNumberOfMessages);
adapter.setVisibilityTimeout(this.visibilityTimeout);
adapter.setSendTimeout(this.sendTimeout);
adapter.setWaitTimeOut(this.waitTimeOut);
adapter.setMessageDeletionPolicy(SqsMessageDeletionPolicy.ON_SUCCESS);
adapter.setTaskExecutor(amazonSQSRequestListenerContainerConsumerPool());
return adapter;
}
#Bean
#SuppressWarnings("unchecked")
IntegrationFlow sqsRequestIntegrationFlow() {
SqsEventHandlerDispatcher commandHandler = applicationContext.getBean(SqsEventHandlerDispatcher.class);
return IntegrationFlows.from(sqsMessageDrivenChannelAdapter())
.transform(converter::toEvent)
.log()
.handle(commandHandler, "handle", a -> a.async(true))
.log()
.get();
}
}
This is my handler:
#Slf4j
#Component
#MessageEndpoint
public class SqsEventHandlerDispatcher {
/**
...
...
**/
public ListenableFuture<?> handle(EventMessage event) {
return new ListenableFutureTask<Void>(() -> doHandle(event), null);
}
private void doHandle(EventMessage event) {
//my handling logic
}
}
The logic in doHandle() method is never reached.
Same integration flow with a sync handler which will return void works perfectly:
#Bean
#SuppressWarnings("unchecked")
IntegrationFlow sqsRequestIntegrationFlow() {
SqsEventHandlerDispatcher commandHandler = applicationContext.getBean(SqsEventHandlerDispatcher.class);
return IntegrationFlows.from(sqsMessageDrivenChannelAdapter())
.transform(converter::toEvent)
.log()
.handle(commandHandler, "handle")
.log()
.get();
}
===============================================================================
#Slf4j
#Component
#MessageEndpoint
public class SqsEventHandlerDispatcher {
public void handle(EventMessage event) {
//my handling logic
}
}
Am I missing something? Or can I achieve it by using Mono?
I don't have much experience neither with spring integration nor async processing.

I found a solution using reactive java.
This is how my service activator looks now:
public Mono handle(EventMessage event, #Header(AwsHeaders.ACKNOWLEDGMENT) Acknowledgment acknowledgment) {
return Mono.fromRunnable(() -> doHandle(event)).subscribeOn(Schedulers.elastic())
.doOnSuccess(r -> {
log.trace("Message successfully processed. Will delete it now!");
acknowledgment.acknowledge();
});
}
private void doHandle(EventMessage event) {
//my handling logic
}
I ve also updated the sqs message deletion policy to NEVER and will manually acknowledge when a message was successfully processed and can be deleted.
adapter.setMessageDeletionPolicy(SqsMessageDeletionPolicy.NEVER);

Spring Cloud Stream message is not received through message queue

I have 2 microservices(images and comments) which communicate one with another(discovered by eureka discovery service) using Spring Cloud Stream with broker rabbit mq. I want to send a message from images microservice to comment microservice.
The problem is that CommentController StreamListener method 'save' is not called.
Image Microservice-> CommentController.java:
public CommentController(MeterRegistry meterRegistry) {
this.meterRegistry = meterRegistry;
this.flux = Flux.<Message<Comment>>create(
emitter -> this.commentSink = emitter,
FluxSink.OverflowStrategy.IGNORE)
.publish()
.autoConnect();
}
#PostMapping("/comments")
public Mono<String> addComment(Mono<Comment> newComment) {
if (commentSink != null) {
return newComment
.map(comment -> {
commentSink.next(MessageBuilder
.withPayload(comment)
.setHeader(MessageHeaders.CONTENT_TYPE,
MediaType.APPLICATION_JSON_VALUE)
.build());
return comment;
})
.flatMap(comment -> {
meterRegistry
.counter("comments.produced", "imageId", comment.getImageId())
.increment();
return Mono.just("redirect:/");
});
} else {
return Mono.just("redirect:/");
}
}
#StreamEmitter
#Output(Source.OUTPUT)
public void emit(FluxSender output) {
output.send(this.flux);
}
Comment Microservice -> CommentService.java
#StreamListener
#Output(Processor.OUTPUT)
public Flux<Void> save(#Input(Processor.INPUT) Flux<Comment> newComment) {
return repository
.saveAll(newComment)
.flatMap(comment -> {
meterRegistry
.counter("comments.consumed", "imageId", comment.getImageId())
.increment();
return Mono.empty();
});
}
CommentService.java->#Service
#EnableBinding(Processor.class)
public class CommentService { ....
Repository which I cloned Chapter7/part 1
Image Microservice -> CommentController.java
Comment Microservice -> CommentService.java

How to handle JmsChannelFactoryBean errors, is there a possibility of custom error channel usage?

I have following configuration for creation of two channels (by using the JmsChannelFactoryBean):
#Bean
public JmsChannelFactoryBean jmsChannel(ActiveMQConnectionFactory activeMQConnectionFactory) {
JmsChannelFactoryBean fb = new JmsChannelFactoryBean(true);
fb.setConnectionFactory(activeMQConnectionFactory);
fb.setDestinationName("something.queue");
fb.setErrorHandler(t -> log.error("something went wrong on jms channel", t));
return fb;
}
#Bean
public JmsChannelFactoryBean jmsChannelDLQ(ActiveMQConnectionFactory activeMQConnectionFactory) {
JmsChannelFactoryBean fb = new JmsChannelFactoryBean(true);
fb.setConnectionFactory(activeMQConnectionFactory);
fb.setDestinationName("something.queue.DLQ");
fb.setErrorHandler(t -> log.error("something went wrong on jms channel", t));
return fb;
}
The something.queue is configured to put the dead letter on something.queue.DLQ. Im using mostly Java DSL to configure the app, and if possible - would like to keep this.
Case is: the message is taken from jmsChannel put to sftp outbound gateway, if there is a problem on sending the file, the message is put back into the jmsChannel as not delivered. After some retries it is designed as poisonus, and put to something.queue.DLQ.
Is it possbile to have the info on error channel when that happens?
What is best practice to handle errors when using JMS backed message channels?
EDIT 2
The integration flow is defined as:
IntegrationFlows.from(filesToProcessChannel).handle(outboundGateway)
Where filesToProcessChannel is the JMS backed channel and outbound gateway is defined as:
#Bean
public SftpOutboundGateway outboundGateway(SftpRemoteFileTemplate sftpRemoteFileTemplate) {
SftpOutboundGateway gateway = new SftpOutboundGateway(sftpRemoteFileTemplate, AbstractRemoteFileOutboundGateway.Command.PUT.getCommand(), EXPRESSION_PAYLOAD);
ArrayList<Advice> adviceChain = new ArrayList<>();
adviceChain.add(errorHandlingAdvice());
gateway.setAdviceChain(adviceChain);
return gateway;
}
Im trying to grab exception using advice:
#Bean
public Advice errorHandlingAdvice() {
RequestHandlerRetryAdvice advice = new RequestHandlerRetryAdvice();
RetryTemplate retryTemplate = new RetryTemplate();
SimpleRetryPolicy retryPolicy = new SimpleRetryPolicy();
retryPolicy.setMaxAttempts(1);
retryTemplate.setRetryPolicy(retryPolicy);
advice.setRetryTemplate(retryTemplate);
advice.setRecoveryCallback(new ErrorMessageSendingRecoverer(filesToProcessErrorChannel));
return advice;
}
Is this the right way?
EDIT 3
There is certanly something wrong with SFTPOutboundGateway and advices (or with me :/):
I used the folowing advice from the spring integration reference:
#Bean
public Advice expressionAdvice() {
ExpressionEvaluatingRequestHandlerAdvice advice = new ExpressionEvaluatingRequestHandlerAdvice();
advice.setSuccessChannelName("success.input");
advice.setOnSuccessExpressionString("payload + ' was successful'");
advice.setFailureChannelName("failure.input");
advice.setOnFailureExpressionString(
"payload + ' was bad, with reason: ' + #exception.cause.message");
advice.setTrapException(true);
return advice;
}
#Bean
public IntegrationFlow success() {
return f -> f.handle(System.out::println);
}
#Bean
public IntegrationFlow failure() {
return f -> f.handle(System.out::println);
}
And when I use :
return IntegrationFlows.from(filesToProcessChannel)
.handle((GenericHandler<File>) (payload, headers) -> {
if (payload.equals("x")) {
return null;
}
else {
throw new RuntimeException("some failure");
}
}, spec -> spec.advice(expressionAdvice()))
It gets called, and i get error message printed out (and that is expected), but when I try to use:
return IntegrationFlows.from(filesToProcessChannel)
.handle(outboundGateway, spec -> spec.advice(expressionAdvice()))
The advice is not called, and the error message is put back to JMS.
The app is using Spring Boot v2.0.0.RELEASE, Spring v5.0.4.RELEASE.
EDIT 4
I managed to resolve the advice issue using following configuration, still don't understand why the handler spec will not work:
#Bean
IntegrationFlow files(SftpOutboundGateway outboundGateway,
...
) {
return IntegrationFlows.from(filesToProcessChannel)
.handle(outboundGateway)
...
.log(LoggingHandler.Level.INFO)
.get();
}
#Bean
public SftpOutboundGateway outboundGateway(SftpRemoteFileTemplate sftpRemoteFileTemplate) {
SftpOutboundGateway gateway = new SftpOutboundGateway(sftpRemoteFileTemplate, AbstractRemoteFileOutboundGateway.Command.PUT.getCommand(), EXPRESSION_PAYLOAD);
ArrayList<Advice> adviceChain = new ArrayList<>();
adviceChain.add(expressionAdvice());
gateway.setAdviceChain(adviceChain);
return gateway;
}
#Bean
public ExpressionEvaluatingRequestHandlerAdvice expressionAdvice() {
ExpressionEvaluatingRequestHandlerAdvice advice = new ExpressionEvaluatingRequestHandlerAdvice();
advice.setSuccessChannelName("success.input");
advice.setOnSuccessExpressionString("payload + ' was successful'");
advice.setFailureChannelName("failure.input");
advice.setOnFailureExpressionString(
"payload + ' was bad, with reason: ' + #exception.cause.message");
advice.setTrapException(true);
return advice;
}
#Bean
public IntegrationFlow success() {
return f -> f.handle(System.out::println);
}
#Bean
public IntegrationFlow failure() {
return f -> f.handle(System.out::println);
}

Since the movement to the DLQ is performed by the broker, the application has no mechanism to log the situation - it is not even aware that it happened.
You would have to catch the exceptions yourself and publish the message the the DLQ yourself, after some number of attempts (JMSXDeliveryCount header), instead of using the broker policy.
EDIT
Add an Advice to the .handle() step.
.handle(outboundGateway, e -> e.advice(myAdvice))
Where myAdvice implements MethodInterceptor.
In the invoke method, after a failure, you can check the delivery count header and, if it exceeds your threshold, publish the message to the DLQ (e.g. send it to another channel that has a JMS outbound adapter subscribed) and log the error; if the threshold has not been exceeded, simply return the result of the invocation.proceed() (or rethrow the exception).
That way, you control publishing to the DLQ rather than having the broker do it. You can also add more information, such as the exception, to headers.
EDIT2
You need something like this
public class MyAdvice implements MethodInterceptor {
#Autowired
private MessageChannel toJms;
public Object invoke(MethodInvocation invocation) throws Throwable {
try {
return invocation.proceed();
}
catch Exception(e) {
Message<?> message = (Message<?>) invocation.getArguments()[0];
Integer redeliveries = messasge.getHeader("JMXRedeliveryCount", Integer.class);
if (redeliveries != null && redeliveries > 3) {
this.toJms.send(message); // maybe rebuild with additional headers about the error
}
else {
throw e;
}
}
}
}
(it should be close, but I haven't tested it). It assumes your broker populates that header.

Spring Batch Integration Remote Chunking error - Message contained wrong job instance id [25] should have been [24]

I'm running into this bug (more info here) which appears to mean that for multi-threaded batches using remote chunking you can't use a common response channel. I'm not exactly sure how to proceed to get this working. Surely there's a way to get this working, because without it I can't see much benefit to remote chunking.
Here's my DSL config that creates a JobRequest:
#Bean
IntegrationFlow newPollingJobsAdapter(JobLaunchingGateway jobLaunchingGateway) {
// Start by polling the DB for new PollingJobs according to the polling rate
return IntegrationFlows.from(jdbcPollingChannelAdapter(),
c -> c.poller(Pollers.fixedRate(10000)
// Do the polling on one of 10 threads.
.taskExecutor(Executors.newFixedThreadPool(10))
// pull out up to 100 new ids for each poll.
.maxMessagesPerPoll(100)))
.log(LoggingHandler.Level.WARN)
// The polling adapter above returns a list of ids. Split them out into
// individual ids
.split()
// Now push each one onto a separate thread for batch processing.
.channel(MessageChannels.executor(Executors.newFixedThreadPool(10)))
.log(LoggingHandler.Level.WARN)
// Transform each one into a JobLaunchRequest
.<Long, JobLaunchRequest>transform(id -> {
logger.warn("Creating job for ID {}", id);
JobParametersBuilder builder = new JobParametersBuilder()
.addLong("polling-job-id", id, true);
return new JobLaunchRequest(job, builder.toJobParameters());
})
.handle(jobLaunchingGateway)
// TODO: Notify somebody? No idea yet
.<JobExecution>handle(exec -> System.out.println("GOT EXECUTION: " + exec))
.get();
}
Nothing in here is particularly special, no odd configs that I'm aware of.
The job itself is pretty straight-forward, too:
/**
* This is the definition of the entire batch process that runs polling.
* #return
*/
#Bean
Job pollingJobJob() {
return jobBuilderFactory.get("pollingJobJob")
.incrementer(new RunIdIncrementer())
// Ship it down to the slaves for actual processing
.start(remoteChunkingStep())
// Now mark it as complete
.next(markCompleteStep())
.build();
}
/**
* Sends the job to a remote slave via an ActiveMQ-backed JMS queue.
*/
#Bean
TaskletStep remoteChunkingStep() {
return stepBuilderFactory.get("polling-job-step-remote-chunking")
.<Long, String>chunk(20)
.reader(runningPollingJobItemReader)
.processor(toJsonProcessor())
.writer(chunkWriter)
.build();
}
/**
* This step just marks the PollerJob as Complete.
*/
#Bean
Step markCompleteStep() {
return stepBuilderFactory.get("polling-job-step-mark-complete")
// We want each PollerJob instance to be a separate job in batch, and the
// reader is using the id passed in via job params to grab the one we want,
// so we don't need a large chunk size. One at a time is fine.
.<Long, Long>chunk(1)
.reader(runningPollingJobItemReader)
.processor(new PassThroughItemProcessor<Long>())
.writer(this.completeStatusWriter)
.build();
}
Here's the chunk writer config:
/**
* This is part of the bridge between the spring-batch and spring-integration. Nothing special or weird is going
* on, so see the RemoteChunkHandlerFactoryBean for a description.
*/
#Bean
RemoteChunkHandlerFactoryBean<PollerJob> remoteChunkHandlerFactoryBean() {
RemoteChunkHandlerFactoryBean<PollerJob> factory = new RemoteChunkHandlerFactoryBean<>();
factory.setChunkWriter(chunkWriter);
factory.setStep(remoteChunkingStep());
return factory;
}
/**
* This is the writer that will actually send the chunk to the slaves. Note that it also configures the
* internal channel on which replies are expected.
*/
#Bean
#StepScope
ChunkMessageChannelItemWriter<String> chunkWriter() {
ChunkMessageChannelItemWriter<String> writer = new ChunkMessageChannelItemWriter<>();
writer.setMessagingOperations(batchMessagingTemplate());
writer.setReplyChannel(batchResponseChannel());
writer.setThrottleLimit(1000);
return writer;
}
The problem seems to be that last section sets up the ChunkMessageChannelItemWriter such that the replyChannel is the same one used by all of the writers, despite each writer being step-scoped. It would seem that I need to add a replyChannel header to one of the messages, but I'm not sure where in the chain to do that or how to process that (if I need to at all?).
Also, this is being sent to the slaves via JMS/ActiveMQ and I'd like to avoid having just a stupid number of nearly-identical queues on ActiveMQ just to support this.
What are my options?

Given that you are using a shared JMS infrastructure, you will need a router to get the responses back to the correct chunk writer.
If you use prototype scope on the batchResponseChannel() #Bean; you'll get a unique channel for each writer.
I don't have time to figure out how to set up a chunked batch job so the following simulates your environment (non-singleton bean that needs a unique reply channel for each instance). Hopefully it's self-explanatory...
#SpringBootApplication
public class So44806067Application {
public static void main(String[] args) {
ConfigurableApplicationContext context = SpringApplication.run(So44806067Application.class, args);
SomeNonSingletonNeedingDistinctRequestAndReplyChannels chunker1 = context
.getBean(SomeNonSingletonNeedingDistinctRequestAndReplyChannels.class);
SomeNonSingletonNeedingDistinctRequestAndReplyChannels chunker2 = context
.getBean(SomeNonSingletonNeedingDistinctRequestAndReplyChannels.class);
if (chunker1.equals(chunker2)) {
throw new IllegalStateException("Expected different instances");
}
chunker1.sendSome();
chunker2.sendSome();
ChunkResponse results = chunker1.getResults();
if (results == null) {
throw new IllegalStateException("No results1");
}
if (results.getJobId() != 1L) {
throw new IllegalStateException("Incorrect routing1");
}
results = chunker2.getResults();
if (results == null) {
throw new IllegalStateException("No results2");
}
if (results.getJobId() != 2L) {
throw new IllegalStateException("Incorrect routing2");
}
context.close();
}
#Bean
public Map<Long, PollableChannel> registry() {
// TODO: should clean up entry for jobId when job completes.
return new ConcurrentHashMap<>();
}
#Bean
#Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public SomeNonSingletonNeedingDistinctRequestAndReplyChannels chunker() {
MessagingTemplate template = template();
final PollableChannel replyChannel = replyChannel();
SomeNonSingletonNeedingDistinctRequestAndReplyChannels bean =
new SomeNonSingletonNeedingDistinctRequestAndReplyChannels(template, replyChannel);
AbstractSubscribableChannel requestChannel = (AbstractSubscribableChannel) template.getDefaultDestination();
requestChannel.addInterceptor(new ChannelInterceptorAdapter() {
#Override
public Message<?> preSend(Message<?> message, MessageChannel channel) {
registry().putIfAbsent(((ChunkRequest<?>) message.getPayload()).getJobId(), replyChannel);
return message;
}
});
BridgeHandler bridge = bridge();
requestChannel.subscribe(bridge);
return bean;
}
#Bean
#Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public MessagingTemplate template() {
MessagingTemplate messagingTemplate = new MessagingTemplate();
messagingTemplate.setDefaultChannel(requestChannel());
return messagingTemplate;
}
#Bean
#Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public DirectChannel requestChannel() {
return new DirectChannel();
}
#Bean
#Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public PollableChannel replyChannel() {
return new QueueChannel();
}
#Bean
#Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public BridgeHandler bridge() {
BridgeHandler bridgeHandler = new BridgeHandler();
bridgeHandler.setOutputChannel(outboundChannel());
return bridgeHandler;
}
#Bean
public DirectChannel outboundChannel() {
return new DirectChannel();
}
#Bean
public DirectChannel masterReplyChannel() {
return new DirectChannel();
}
#ServiceActivator(inputChannel = "outboundChannel")
public void simulateJmsChannelAdapterPair(ChunkRequest<?> request) {
masterReplyChannel()
.send(new GenericMessage<>(new ChunkResponse(request.getSequence(), request.getJobId(), null)));
}
#Router(inputChannel = "masterReplyChannel")
public MessageChannel route(ChunkResponse reply) {
// TODO: error checking - missing reply channel for jobId
return registry().get(reply.getJobId());
}
public static class SomeNonSingletonNeedingDistinctRequestAndReplyChannels {
private final static AtomicLong jobIds = new AtomicLong();
private final long jobId = jobIds.incrementAndGet();
private final MessagingTemplate template;
private final PollableChannel replyChannel;
public SomeNonSingletonNeedingDistinctRequestAndReplyChannels(MessagingTemplate template,
PollableChannel replyChannel) {
this.template = template;
this.replyChannel = replyChannel;
}
public void sendSome() {
ChunkRequest<String> cr = new ChunkRequest<>(0, Collections.singleton("foo"), this.jobId, null);
this.template.send(new GenericMessage<>(cr));
}
public ChunkResponse getResults() {
#SuppressWarnings("unchecked")
Message<ChunkResponse> received = (Message<ChunkResponse>) this.replyChannel.receive(10_000);
if (received != null) {
if (received.getPayload().getJobId().equals(this.jobId)) {
System.out.println("Got the right one");
}
else {
System.out.println(
"Got the wrong one " + received.getPayload().getJobId() + " instead of " + this.jobId);
}
return received.getPayload();
}
return null;
}
}
}