I was trying to understand how container managed transactions are handled for asynchronous jax-rs client in JBOSS.
If the following code is executed within a transaction in JBOSS then does the same transaction continue when the asynchronous response is received in another thread? Or does JBOSS end the transaction when the requesting thread completes (response comes on different thread)?
Client client = ClientBuilder.newClient();
final WebTarget target = client.target("http://quote.com/quote/RHT");
target.request().async().get(new InvocationCallback<String> {
public void completed(String quote) {
System.out.println("RHT: " + quote);
}
public void failed(Throwable t) {}
}
Based on experiment, it appears the transaction continues until the async operation is completed.
Related
I have a scenario in which I am calling RegisterMessageHandler of SubscriptionClient class of Azure Service Bus library.
Basically I am using trigger based approach while receiving the messages from Service Bus in one of my services in Service Fabric Environment as a stateless service.
So I am not closing the subscriptionClient object immediately, rather I am keeping it open for the lifetime of the Service so that it keeps on receiving the message from azure service bus topics.
And when the service needs to shut down(due to some reasons), I want to handle the cancellation token being passed into the service of Service Fabric.
My question is how can I handle the cancellation token in the RegisterMessageHandler method which gets called whenever a new message is received?
Also I want to handle the closing of the Subscription client "Gracefully", i.e I want that if a message is already being processed, then I want that message to get processed completely and then I want to close the connection.
Below is the code I am using.
Currently We are following the below approach:
1. Locking the process of the message using semaphore lock and releasing the lock in finally block.
2. Calling the cancellationToken.Register method to handle cancellation token whenever cancellation is done. Releasing the lock in the Register Method.
public class AzureServiceBusReceiver
{
private SubscriptionClient subscriptionClient;
private static Semaphore semaphoreLock;
public AzureServiceBusReceiver(ServiceBusReceiverSettings settings)
{
semaphoreLock = new Semaphore(1, 1);
subscriptionClient = new SubscriptionClient(
settings.ConnectionString, settings.TopicName, settings.SubscriptionName, ReceiveMode.PeekLock);
}
public void Receive(
CancellationToken cancellationToken)
{
var options = new MessageHandlerOptions(e =>
{
return Task.CompletedTask;
})
{
AutoComplete = false,
};
subscriptionClient.RegisterMessageHandler(
async (message, token) =>
{
semaphoreLock.WaitOne();
if (subscriptionClient.IsClosedOrClosing)
return;
CancellationToken combinedToken = CancellationTokenSource.CreateLinkedTokenSource(cancellationToken, token).Token;
try
{
// message processing logic
}
catch (Exception ex)
{
await subscriptionClient.DeadLetterAsync(message.SystemProperties.LockToken);
}
finally
{
semaphoreLock.Release();
}
}, options);
cancellationToken.Register(() =>
{
semaphoreLock.WaitOne();
if (!subscriptionClient.IsClosedOrClosing)
subscriptionClient.CloseAsync().GetAwaiter().GetResult();
semaphoreLock.Release();
return;
});
}
}
Implement the message client as ICommunicationListener, so when the service is closed, you can block the call until message processing is complete.
Don't use a static Semaphore, so you can safely reuse the code within your projects.
Here is an example of how you can do this.
And here's the Nuget package created by that code.
And feel free to contribute!
I have read another issue in this website like this but I don't get how to resolve the issue.
Spring Integration: Application leaking SimpleAsyncTaskExecutor threads?
My error is similar to previous link
SimpleAsyncTaskExecutor-2327" - Thread t#2405
java.lang.Thread.State: WAITING
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <7a224c1> (a java.util.concurrent.CountDownLatch$Sync)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:836)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:997)
at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1304)
at java.util.concurrent.CountDownLatch.await(CountDownLatch.java:231)
at org.springframework.messaging.core.GenericMessagingTemplate$TemporaryReplyChannel.receive(GenericMessagingTemplate.java:199)
at org.springframework.messaging.core.GenericMessagingTemplate$TemporaryReplyChannel.receive(GenericMessagingTemplate.java:192)
at org.springframework.messaging.core.GenericMessagingTemplate.doReceive(GenericMessagingTemplate.java:130)
at org.springframework.messaging.core.GenericMessagingTemplate.doSendAndReceive(GenericMessagingTemplate.java:157)
at org.springframework.messaging.core.GenericMessagingTemplate.doSendAndReceive(GenericMessagingTemplate.java:45)
at org.springframework.messaging.core.AbstractMessagingTemplate.sendAndReceive(AbstractMessagingTemplate.java:42)
at org.springframework.integration.core.MessagingTemplate.sendAndReceive(MessagingTemplate.java:97)
at org.springframework.integration.core.MessagingTemplate.sendAndReceive(MessagingTemplate.java:38)
at org.springframework.messaging.core.AbstractMessagingTemplate.convertSendAndReceive(AbstractMessagingTemplate.java:79)
at org.springframework.messaging.core.AbstractMessagingTemplate.convertSendAndReceive(AbstractMessagingTemplate.java:70)
at org.springframework.integration.gateway.MessagingGatewaySupport.doSendAndReceive(MessagingGatewaySupport.java:449)
I'm using
spring-integration-java-dsl-1.2.3.RELEASE
spring-integration-ip-4.3.17.RELEASE
spring-integration-http-4.3.17.RELEASE
My scenario is the next: I receive a message throught a Api Controller and this message is sent a un TCP socket.
I have defined a MessageGateway interface
#MessagingGateway(defaultRequestChannel = "toTcp.input")
public interface MessageTcpGateway {
#Gateway
public ListenableFuture<Void> sendTcpChannel(byte[] data,
#Header("connectionId") String connectionId );
}
After I use this interface in a service class like this:
public void sendMessageTcpGateway(final String bridgeId,final String connectionId, final byte[] message) {
LOGGER.debug("sendMessageTcpGateway connectionId:{} - message:{}", connectionId, message);
if (holder.existsConnection(connectionId)!=null) {
gatewayTcp.sendTcpChannel(message,connectionId);
} else {
LOGGER.error("Not send message connectionId:{} - message:{}", connectionId, message);
}
}
Why the thread is waiting ?. Is my process waiting for any kind of sign and I'm not considered?. I guess that if the connection is not available or whatever kind of error, spring-integration will throw a exception
How can i resolve this issue?
I wonder why don't follow recommendations from that SO thread...
The ListenableFuture<Void> is a bottleneck in your solution. As you see by stack trace you have there doSendAndReceive(), but I guess your target solution is really one-way and doesn't return anything for the replyChannel in headers.
You should consider to have just plain void return type and an ExecutorChannel downstream.
Unfortunately we can't detect such a situation from the framework side since a Future return type of the gateway method indicates that you are going to perform request-reply async manner. In your case it is just an async request, nothing more.
I have a spring integration flow which produces messages that should be kept around waiting for an appropriate consumer to come along and consume them.
#Bean
public IntegrationFlow messagesPerCustomerFlow() {
return IntegrationFlows.
from(WebFlux.inboundChannelAdapter("/messages/{customer}")
.requestMapping(r -> r
.methods(HttpMethod.POST)
)
.requestPayloadType(JsonNode.class)
.headerExpression("customer", "#pathVariables.customer")
)
.channel(messagesPerCustomerQueue())
.get();
}
#Bean(name = PollerMetadata.DEFAULT_POLLER)
public PollerSpec poller() {
return Pollers.fixedRate(100);
}
#Bean
public QueueChannel messagesPerCustomerQueue() {
return MessageChannels.queue()
.get();
}
The messages in the queue should be delivered as server-sent events via http as shown below.
The PublisherSubscription is just a holder for the Publisher and the IntegrationFlowRegistration, the latter is used to destroy the dynamically created flow when it is no longer needed (note that the incoming message for the GET has no content, which is not handled properly ATM by the Webflux integration, hence a small workaround is necessary to get access to the path variable shoved to the customer header):
#Bean
public IntegrationFlow eventMessagesPerCustomer() {
return IntegrationFlows
.from(WebFlux.inboundGateway("/events/{customer}")
.requestMapping(m -> m.produces(TEXT_EVENT_STREAM_VALUE))
.headerExpression("customer", "#pathVariables.customer")
.payloadExpression("''") // neeeded to make handle((p,h) work
)
.log()
.handle((p, h) -> {
String customer = h.get("customer").toString();
PublisherSubscription<JsonNode> publisherSubscription =
subscribeToMessagesPerCustomer(customer);
return Flux.from(publisherSubscription.getPublisher())
.map(Message::getPayload)
.doFinally(signalType ->
publisherSubscription.unsubscribe());
})
.get();
}
The above request for server-sent events dynamically registers a flow which subscribes to the queue channel on demand with a selective consumer realized by a filter with throwExceptionOnRejection(true). Following the spec for Message Handler chain that should ensure that the message is offered to all consumers until one accepts it.
public PublisherSubscription<JsonNode> subscribeToMessagesPerCustomer(String customer) {
IntegrationFlowBuilder flow = IntegrationFlows.from(messagesPerCustomerQueue())
.filter("headers.customer=='" + customer + "'",
filterEndpointSpec -> filterEndpointSpec.throwExceptionOnRejection(true));
Publisher<Message<JsonNode>> messagePublisher = flow.toReactivePublisher();
IntegrationFlowRegistration registration = integrationFlowContext.registration(flow.get())
.register();
return new PublisherSubscription<>(messagePublisher, registration);
}
This construct works in principle, but with the following issues:
Messages sent to the queue while there are no subscribers at all lead to a MessageDeliveryException: Dispatcher has no subscribers for channel 'application.messagesPerCustomerQueue'
Messages sent to the queue while no matching subscriber is present yet lead to an AggregateMessageDeliveryException: All attempts to deliver Message to MessageHandlers failed.
What I want is that the message remains in the queue and is repeatedly offered to all subscribers until it is either consumed or expires (a proper selective consumer). How can I do that?
note that the incoming message for the GET has no content, which is not handled properly ATM by the Webflux integration
I don't understand this concern.
The WebFluxInboundEndpoint works with this algorithm:
if (isReadable(request)) {
...
else {
return (Mono<T>) Mono.just(exchange.getRequest().getQueryParams());
}
Where GET method really goes to the else branch. And the payload of the message to send is a MultiValueMap. And also we recently fixed with you the problem for the POST, which is released already as well in version 5.0.5: https://jira.spring.io/browse/INT-4462
Dispatcher has no subscribers
Can't happen on the QueueChannel in principle. There is no any dispatcher on there at all. It is just queue and sender offers message to be stored. You are missing something else to share with us. But let's call things with its own names: the messagesPerCustomerQueue is not a QueueChannel in your application.
UPDATE
Regarding:
What I want is that the message remains in the queue and is repeatedly offered to all subscribers until it is either consumed or expires (a proper selective consumer)
Only what we see is a PollableJmsChannel based on the embedded ActiveMQ to honor TTL for messages. As a consumer of this queue you should have a PublishSubscribeChannel with the setMinSubscribers(1) to make MessagingTemplate to throw a MessageDeliveryException when there is no subscribers yet. This way a JMS transaction will be rolled back and message will return to the queue for the next polling cycle.
The problem with in-memory QueueChannel that there is no transactional redelivery and message once polled from that queue is going to be lost.
Another option is similar to JMS (transactional) is a JdbcChannelMessageStore for the QueueChannel. Although this way we don't have a TTL functionality...
I created a Spring Boot (1.4.2) REST application. One of the #RestController methods needs to invoke a 3rd party API REST operation (RestOp1) which returns, say between 100-250 records. For each of those records returned by RestOp1, within the same method, another REST operation of the same 3rd party API (RestOp2) must be invoked. My first attempt involved using a Controller class level ExecutorService based on a Fixed Thread Pool of size 100, and a Callable returning a record corresponding to the response of RestOp2:
// Executor thread pool - declared and initialized at class level
ExecutorService executor = Executors.newFixedThreadPool(100);
// Get records from RestOp1
ResponseEntity<RestOp1ResObj[]> restOp1ResObjList
= this.restTemplate.exchange(url1, HttpMethod.GET, httpEntity, RestOp1ResObj[].class);
RestOp1ResObj[] records = restOp1ResObjList.getBody();
// Instantiate a list of futures (to call RestOp2 for each record)
List<Future<RestOp2ResObj>> futureList = new ArrayList<>();
// Iterate through the array of records and call RestOp2 in a concurrent manner, using Callables.
for (int count=0; count<records.length; count++) {
Future<RestOp2ResObj> future = this.executorService.submit(new Callable<RestOp2ResObj>() {
#Override
public RestOp2ResObj call() throws Exception {
return this.restTemplate.exchange(url2, HttpMethod.GET, httpEntity, RestOp2Obj.class);
}
};
futureList.add(future);
});
// Iterate list of futures and fetch response from RestOp2 for each
// record. Build a final response and send back to the client.
for (int count=0; count<futureList.size(); count++) {
RestOp2ResObj response = futureList.get(count).get();
// use above response to build a final response for all the records.
}
The performance of the above code is abysmal to say the least. The response time for a RestOp1 call (invoked only once) is around 2.5 seconds and that for a RestOp2 call (invoked for each record) is about 1.5 seconds. But the code execution time is between 20-30 seconds, as opposed to an expected range of 5-6 seconds! Am I missing something fundamental here?
Is the service you are calling fast enough to handle that many requests per second?
There is an async version of RestService is available called AsyncRestService. Why are you not using that?
I would probably go like this:
AsyncRestTemplate asyncRestTemplate = new AsyncRestTemplate(new ConcurrentTaskExecutor(Executors.newFixedThreadPool(100)));
asyncRestTemplate.exchange("http://www.example.com/myurl", HttpMethod.GET, new HttpEntity<>("message"), String.class)
.addCallback(new ListenableFutureCallback<ResponseEntity<String>>() {
#Override
public void onSuccess(ResponseEntity<String> result) {
//TODO: Add real response handling
System.out.println(result);
}
#Override
public void onFailure(Throwable ex) {
//TODO: Add real logging solution
ex.printStackTrace();
}
});
Your question involves two parts :
multiple API callbacks asynchronously
handle timeouts (fallback)
both parts are related as you've to handle the timeout of each call.
you may consider use Spring Cloud (based on spring boot) and use some out of the box solution based on OSS Netflix stacks.
The first (timeouts) on should be a circuit breaker hystrix based on feign client
The second (multiple requests) this is an architecture issue, using native Executors isn't a good idea as it will not scale and has a huge maintenance costs. You may relay on Spring Asynchrounous Methods you'll have better results and fully spring compliant.
Hope this will help.
My requirements are stated below:
I have to develop a wrapper service on top a queue,so i was just going through some message Queue like (ActiveMQ,Apollo,Kafka). But decided to proceed with ActiveMQ to match our usecases.Now the requirement are as follows:
1) A restful api through which different publisher will publish to queue,based on clientId queue will be selected.
2) Consumer will consume message through restful api and will consume message in batches. say consumer as for something like give me 10 message from queue.
Now the service should provide 10 message if there is 10 message or if message number is less or zero it will send accordingly. After receiving the message the client will process with the message and send back acknowledgement through different res-full uri. upon receiving that acknowledgement,the MQService should commit or rollback message from the queue.
In order to this in the MQService layer, i have used a cached,where im keeping the JMS connection and session object till acknowledgemnt is received or ttl expire.
In-order to retrieve message in batches and send back to client, i have created a multi-threaded consumer,so that for 5 batch message request,the service layer will create 5 thread each having different connection and session object( as stated in ActiveMQ multiple consumer http://activemq.apache.org/multiple-consumers-on-a-queue.html)
Basic use-case:
MQ(BROKER)[A] --> Wrapper(MQService)[B]-->Client [C]
Note:[B] is a restfull service having JMS consumer implemented in it.It keeps the connection and session object in cache.
[C] request to [B] to give 3 message
[B] must fetch 3 message if available in queue,wrap it in batchmsgFormat and send it to [C]
[C] process the message and send acknowledgemnt suces/failed to [B] through /send-ack uri.
Upon receiving Ack from [C], [B] will commit the Jms session and close the session and connection object. Also it will evict those from the cache.
The above work-flow is working fine with single message fetching.
But the queue hungs up on JMS MesageConsumer.receive() when try to fetch message with mutilple consumer using multithreading. ...
Here the JMS Consumer code in MQService layer:
----------------------------------------------
public BatchMessageFormat getConsumeMsg(final String clientId, final Integer batchSize) throws Exception {
BatchMessageFormat batchmsgFormat = new BatchMessageFormat();
List<MessageFormat> msgdetails = new ArrayList<MessageFormat>();
List<Future<MessageFormat>> futuremsgdetails = new ArrayList<Future<MessageFormat>>();
if (batchSize != null) {
Integer msgCount = getMsgCount(clientId, batchSize);
for (int batchconnect = 0; batchconnect <msgCount; batchconnect++) {
FutureTask<MessageFormat> task = new FutureTask<MessageFormat>(new Callable<MessageFormat>() {
#Override
public MessageFormat call() throws Exception {
MessageFormat msg=consumeBatchMsg(clientId,batchSize);
return msg;
}
});
futuremsgdetails.add(task);
Thread t = new Thread(task);
t.start();
}
for(Future<MessageFormat> msg:futuremsgdetails){
msgdetails.add(msg.get());
}
batchmsgFormat.setMsgDetails(msgdetails);
return batchmsgFormat
}
Message fetching:
private MessageFormat consumeBatchMsg(String clientId, Integer batchSize) throws JMSException, IOException{
MessageFormat msgFormat= new MessageFormat();
Connection qC = ConnectionUtil.getConnection();
qC.start();
Session session = qC.createSession(true, -1);
Destination destination = createQueue(clientId, session);
MessageConsumer consumer = session.createConsumer(destination);
Message message = consumer.receive(2000);
if (message!=null || message instanceof TextMessage) {
TextMessage textMessage = (TextMessage) message;
msgFormat.setMessageID(textMessage.getJMSMessageID());
msgFormat.setMessage(textMessage.getText());
CacheObject cacheValue = new CacheObject();
cacheValue.setConnection(qC);
cacheValue.setSession(session);
cacheValue.setJmsQueue(destination);
MQCache.instance().add(textMessage.getJMSMessageID(),cacheValue);
}
consumer.close();
return msgFormat;
}
Acknowledgement and session closing:
public String getACK(String clientId,String msgId,String ack)throws JMSException{
if (MQCache.instance().get(msgId) != null) {
Connection connection = MQCache.instance().get(msgId).getConnection();
Session session = MQCache.instance().get(msgId).getSession();
Destination destination = MQCache.instance().get(msgId).getJmsQueue();
MessageConsumer consumer = session.createConsumer(destination);
if (ack.equalsIgnoreCase("SUCCESS")) {
session.commit();
} else {
session.rollback();
}
session.close();
connection.close();
MQCache.instance().evictCache(msgId);
return "Accepted";
} else {
return "Rejected";
}
}
Does anyone worked on similar scenario or can you pls throw some light? Is there any other way to implement this batch mesage fetching as well as client failure handling?
Try after setting the prefetch limit to 0 as below:
ConnectionFactory connectionFactory
= new ActiveMQConnectionFactory("tcp://localhost:61616?jms.prefetchPolicy.queuePrefetch=0");
I'll give a few pointers to help to code this logic better.
I'm assuming you are using pure JMS 1.1 as much as possible. Ensure that you have one place where you get the connection from the pool or create a connection. You need not do that inside a thread. You can do that outside. Sessions must be created inside a thread and shouldn't be shared. This will impact the logic in the function consumeBatchMsg().
Secondly, its simpler to use one thread to consume all the messages of the given batchSize. I see that you are using transacted session. So you can do one commit after getting all the messages of the batchSize.
If you really want to take the complicated route of having multiple consumers on a queue (probably little better performance), you can using CountDownLatch or CyclicBarrier of Java and set it to batchSize to trigger. Once all the threads have received the messages, it can commit and close the sessions in the respective threads. Never let the session instance go out of the context of the thread that created it.