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RabbitMq: works through times, not as I expect

And so, step by step, what do I want to do:
I receive data if an error occurs when sending to another system, then I want to send data to rabbitMQ:
#Override
public void updateAnketaIfThrowThenSendMessageInRabbit(ProfileId profileId, ChangeClientAnketaRequest anketa, String profileVersion) {
try {
anketaService.updateAnketa(profileId, anketa, profileVersion);
} catch (ClubProNotAvailableException e) {
rabbitTemplate.convertAndSend(config.getExchange(), config.getRoutingKey(), clubProNotAvailableRabbit);
Anketa a = conversionService.convert(conversionService.convert(anketa, UgAnketa.class), Anketa.class);
profileService.updateProfileAnketa(profileId, a, null);
}
}
}
Next, I want to accept these data and queues and try sending them again at a certain time interval.
For this i:
I accept messages
I'm trying to resend it:
a) If everything was successful, I delete it from the queue
b) If an error occurred, I call the stop method for the container. After a certain time I use the scheduler to call the start method for the container
#Override
public void onMessage(Message message, Channel channel) throws IOException {
ClubProNotAvailableRabbit data = null;
try {
data = OBJECT_MAPPER.readValue(message.getBody(), ClubProNotAvailableRabbit.class);
MDC.put(data.getRequestContextRabbit().getRequestId(), UUID.randomUUID().toString());
requestContextService.put(createRequestContext(data.getRequestContextRabbit(), data.getRequestContextRabbit().getFront()));
methodCall(data);
channel.basicAck(message.getMessageProperties().getDeliveryTag(), false);
} catch (ClubProNotAvailableException e) {
listenerContainer.stop();
throw new ClubProNotAvailableException();
}
}
public void startContainer() {
listenerContainer.start();
}
I have encountered such problems:
The message is not delivered to the queue every time. Sometimes I have to call the convert And Send method several times.
When I got messages from the queue and an error occurred, I turn off the container, then when it turns on, the queue is empty, and when I turn off, I see this message:
2020-07-20 21:36:59.878 [INFO ] o.s.a.r.l.SimpleMessageListenerContainer - Workers not finished.
2020-07-20 21:36:59.878 [WARN ] o.s.a.r.l.SimpleMessageListenerContainer - Closing channel for unresponsive consumer: Consumer#77416991: tags=[[amq.ctag-E62UisbYdAAOQIM2bWr08w]], channel=Cached Rabbit Channel: AMQChannel(amqp://usergate_tst#10.64.177.12:5672/,35), conn: Proxy#6c60c170 Shared Rabbit Connection: SimpleConnection#5fb65b3a [delegate=amqp://usergate_tst#10.64.177.12:5672/, localPort= 59801], acknowledgeMode=MANUAL local queue size=0
How can I fix this situation?
CONTINUED QUESTION.
I corrected the code like this:
#Override
public void onMessage(Message message, Channel channel) throws IOException, InterruptedException {
ClubProNotAvailableRabbit data = null;
try {
data = OBJECT_MAPPER.readValue(message.getBody(), ClubProNotAvailableRabbit.class);
MDC.put(data.getRequestContextRabbit().getRequestId(), UUID.randomUUID().toString());
requestContextService.put(createRequestContext(data.getRequestContextRabbit(), data.getRequestContextRabbit().getFront()));
methodCall(data);
channel.basicAck(message.getMessageProperties().getDeliveryTag(), false);
} catch (ClubProNotAvailableException e) {
channel.basicReject(message.getMessageProperties().getDeliveryTag(), true);
Thread.sleep(20000);
}
}
Thread.sleep here for experiment.
I expect that when I grab a message from the queue in the rabbitmq admin console, I will see it go to Unacked status, this is how it happens.
Then, when an error occurs, I call the basicReject method, and I want the status to become ready, immediately after the basicReject call line, but it becomes ready as soon as the method completes completely.
Unacked status:
Although the baseReject method has already worked.
Why is this happening? how is it supposed to work and what mechanism? why doesn't the message become immediately ready (status in console rabbit) after calling the baseReject method?

Closing channel for unresponsive consumer:
This means the listener is "stuck" in your code - you can't call stop() from the listener itself - the container.stop() waits for the listener to exit. You should use stop(() -> log.info("stopped container")) instead.
You need to basicReject in the catch case - the container won't handle it for you with MANUAL acks.
You MUST use MANUAL acks if you ack/nack the message yourself.
It's generally better to let the container take care of acking your messages.

How to receive message from wildfly jms queue using consumer

I encountered a knotty problem when receiving message from WildFly JMS queue. My code is below:
Session produceSession = connectionFactory.createConnection().createSession(false, Session
.CLIENT_ACKNOWLEDGE);
Session consumerSession = connectionFactory.createConnection().createSession(false, Session
.CLIENT_ACKNOWLEDGE);
ApsSchedule apsSchedule = new ApsSchedule();
boolean success;
MessageProducer messageProducer = produceSession.createProducer(outQueueMaxusOrder);
success = apsSchedule.sendD90Order(produceSession,messageProducer, d90OrderAps);
if (!success) {
logger.error("Can't send APS schedule msg ");
} else {
MessageConsumer consumer = consumerSession.createConsumer(inQueueDeliveryDate);
data = apsSchedule.receiveD90Result(consumerSession,consumer);
}
then getting into the receiveD90Result():
public DeliveryData receiveD90Result(Session session, MessageConsumer consumer) {
DeliveryData data = null;
try {
Message message = consumer.receive(10000);
if (message == null) {
return null;
}
TextMessage msg = (TextMessage) message;
String text = msg.getText();
logger.debug("Receive APS d90 result: {}", text);
ObjectMapper mapper = new ObjectMapper();
data = mapper.readValue(text, DeliveryData.class);
} catch (JMSException je) {
logger.error("Can't receive APS d90 order result: {}", je.getMessage());
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
consumer.close();
} catch (JMSException e) {
e.printStackTrace();
}
}
return data;
}
But when implementing the consumer.receive(10000), the project can't get a message from queue. If I use asynchronous way of MDB to listen the queue, I can get the message from queue. How to resolve it?

There are multiple modes you can choose to get a message from the queue. Message Queues are by default asynchronous in usage. There are however cases when you want to read it synchronously , for example sending a message with account number and using another queue to read the response and match it with a message id or a message correlation id. When you do a receive , the program is waiting for a message to arrive within that polling interval specified in receive.
The code snippet you have , as i see it uses the psuedo synchronous approach. If you have to use it as an MDB , you will have to implement message driven bean (EJB Resource) or message listener.
The way that MDB/Message Listener works is more event based , instead of a poll with a timeout (like the receive) , you implement a callback called onMessage() that is invoked every time there is a message. Instead of a synchronous call , this becomes asynchronous. Your application may require some changes both in terms of design.

I don't see where you're calling javax.jms.Connection.start(). In fact, it doesn't look like you even have a reference to the javax.jms.Connection instance used for your javax.jms.MessageConsumer. If you don't have a reference to the javax.jms.Connection then you can't invoke start() and you can't invoke close() when you're done so you'll be leaking connections.
Furthermore, connections are "heavy" objects and are meant to be re-used. You should create a single connection for both the producer and consumer. Also, if your application is not going to use the javax.jms.Session from multiple threads then you don't need multiple sessions either.

Camel: stop the route when the jdbc connection loss is detected

I have an application with the following route:
from("netty:tcp://localhost:5150?sync=false&keepAlive=true")
.routeId("tcp.input")
.transform()
.simple("insert into tamponems (AVIS) values (\"${in.body}\");")
.to("jdbc:mydb");
This route receives a new message every 59 millisecondes. I want to stop the route when the connection to the database is lost, before that a second message arrives. And mainly, I want to never lose a message.
I proceeded that way:
I added an errorHandler:
errorHandler(deadLetterChannel("direct:backup")
.redeliveryDelay(5L)
.maximumRedeliveries(1)
.retryAttemptedLogLevel(LoggingLevel.WARN)
.logExhausted(false));
My errorHandler tries to redeliver the message and if it fails again, it redirects the message to a deadLetterChannel.
The following deadLetterChannel will stop the tcp.input route and try to redeliver the message to the database:
RoutePolicy policy = new StopRoutePolicy();
from("direct:backup")
.routePolicy(policy)
.errorHandler(
defaultErrorHandler()
.redeliveryDelay(1000L)
.maximumRedeliveries(-1)
.retryAttemptedLogLevel(LoggingLevel.ERROR)
)
.to("jdbc:mydb");
Here is the code of the routePolicy:
public class StopRoutePolicy extends RoutePolicySupport {
private static final Logger LOG = LoggerFactory.getLogger(String.class);
#Override
public void onExchangeDone(Route route, Exchange exchange) {
String stop = "tcp.input";
CamelContext context = exchange.getContext();
if (context.getRouteStatus(stop) != null && context.getRouteStatus(stop).isStarted()) {
try {
exchange.getContext().getInflightRepository().remove(exchange);
LOG.info("STOP ROUTE: {}", stop);
context.stopRoute(stop);
} catch (Exception e) {
getExceptionHandler().handleException(e);
}
}
}
}
My problems with this method are:
In my "direct:backup" route, if I set the maximumRedeliveries to -1 the route tcp.input will never stop
I'm loosing messages during the stop
This method for detecting the connection loss and for stopping the route is too long
Please, does anybody have an idea for make this faster or for make this differently in order to not lose message?

I have finally found a way to resolve my problems. In order to make the application faster, I added asynchronous processes and multithreading with seda.
from("netty:tcp://localhost:5150?sync=false&keepAlive=true").to("seda:break");
from("seda:break").threads(5)
.routeId("tcp.input")
.transform()
.simple("insert into tamponems (AVIS) values (\"${in.body}\");")
.to("jdbc:mydb");
I did the same with the backup route.
from("seda:backup")
.routePolicy(policy)
.errorHandler(
defaultErrorHandler()
.redeliveryDelay(1000L)
.maximumRedeliveries(-1)
.retryAttemptedLogLevel(LoggingLevel.ERROR)
).threads(2).to("jdbc:mydb");
And I modified the routePolicy like that:
public class StopRoutePolicy extends RoutePolicySupport {
private static final Logger LOG = LoggerFactory.getLogger(String.class);
#Override
public void onExchangeBegin(Route route, Exchange exchange) {
String stop = "tcp.input";
CamelContext context = exchange.getContext();
if (context.getRouteStatus(stop) != null && context.getRouteStatus(stop).isStarted()) {
try {
exchange.getContext().getInflightRepository().remove(exchange);
LOG.info("STOP ROUTE: {}", stop);
context.stopRoute(stop);
} catch (Exception e) {
getExceptionHandler().handleException(e);
}
}
}
#Override
public void onExchangeDone(Route route, Exchange exchange) {
String stop = "tcp.input";
CamelContext context = exchange.getContext();
if (context.getRouteStatus(stop) != null && context.getRouteStatus(stop).isStopped()) {
try {
LOG.info("RESTART ROUTE: {}", stop);
context.startRoute(stop);
} catch (Exception e) {
getExceptionHandler().handleException(e);
}
}
}
}
With these updates, the TCP route is stopped before the backup route is processed. And the route is restarted when the jdbc connection is back.
Now, thanks to Camel, the application is able to handle a database failure without losing message and without manual intervention.
I hope this could help you.

Rabbit prefetch

I use spring amqp with rabbitmq. I want get one message without prefetch.
I configured with
SimpleMessageListenerContainer container = new SimpleMessageListenerContainer();
container.setConnectionFactory(rabbitConnectionFactory());
container.setQueueNames(
ProjectConfigs.getInstance().get_RABBIT_TASK_QUEUE()
);
container.setMessageListener(taskListener());
container.setConcurrentConsumers(1);
container.setPrefetchCount(1);
container.setTxSize(1);
return container;
How to disable prefetch and get only one message/

prefetch simply controls how many messsages the broker allows to be outstanding at the consumer at a time. When set to 1, this means the broker will send 1 message, wait for the ack, then send the next.
It defaults to 1. Setting it to 0 will mean the broker will send unlimited messages to the consumer, regardless of acks.
If you only want one message and then stop, you shouldn't use a container, you can use one of the RabbitTemplate.receive() methods.

I try do it with Spring AMQP
#Bean
public MessageListener taskListener() {
return new MessageListener() {
public void onMessage(Message message) {
try {
LOGGER.info(new String(message.getBody(), "UTF-8"));
Converter converter = new Converter();
converter.startConvert(new String(message.getBody(), "UTF-8"));
} catch (Exception e) {
LOGGER.error(getStackTrace(e));
}
}
};
}

ActiveMQ register listener to StompConnection

I'm using a variation of the example at http://svn.apache.org/repos/asf/activemq/trunk/assembly/src/release/example/src/StompExample.java to receive message from a queue. What I'm trying to do is to keep listening to a queue and perform some action upon reception of a new message. The problem is that I couldn't find a way to register a listener to any of the related objects. I've tried something like:
public static void main(String args[]) throws Exception {
StompConnection connection = null;
try {
connection = new StompConnection();
connection.open("localhost", 61613);
connection.connect("admin", "activemq");
connection.subscribe("/queue/worker", Subscribe.AckModeValues.AUTO);
while (true) {
StompFrame message = connection.receive();
System.out.println(message.getBody());
}
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
} finally {
if (connection != null) {
connection.disconnect();
}
}
}
but this doesn't work as a time out occurs after a few seconds (java.net.SocketTimeoutException: Read timed out). Is there anything I can do to indefinitely listen to this queue?

ActiveMQ's StompConnection class is a relatively primitive STOMP client. Its not capable of async callbacks on Message or for indefinite waits. You can pass a timeout to receive but depending on whether you are using STOMP v1.1 it could still timeout early if a heart-beat isn't received in time. You can of course always catch the timeout exception and try again.
For STOMP via Java you're better off using StompJMS or the like which behaves like a real JMS client and allows for async Message receipt.

#Tim Bish: I tried StompJMS, but couldn't find any example that I could use (maybe you can provide a link). I 'fixed' the problem by setting the timeout to 0 which seems to be blocking.

even i was facing the same issue.. you can fix this by adding time out to your receive() method.
Declare a long type variable.
long waitTimeOut = 5000; //this is 5 seconds
now modify your receive function like below.
StompFrame message = connection.receive(waitTimeOut);
This will definitely work.