Send and consume message by one connection - activemq

Is there a way to do this? My case: there are connections "A", "B", and "C", that subscribed to the topic with name "Topic 1". "A" sends a message to the topic and it doesn't receive it. "B" and "C" receive this message. If "C" sends a message to topic then it's "A" and "B" who get the message.

Pass true for the noLocal parameter when you create your consumer.
For example, the javax.jms.MessageConsumer#createConsumer method has an overloaded version that takes a javax.jms.Destination, a String, and a boolean. If you specify true for the boolean (i.e. the noLocal parameter) then messages published using that same connection won't be consumed. The JavaDoc says this about the noLocal parameter:
The noLocal argument is for use when the destination is a topic and the session's connection is also being used to publish messages to that topic. If noLocal is set to true then the MessageConsumer will not receive messages published to the topic by its own connection. The default value of this argument is false. If the destination is a queue then the effect of setting noLocal to true is not specified.

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How to set routing key for producer and consumer successfully

I'm building a SpringCloud Stream based application and exchange type is topic and message is sent to 2 queue consumer groups from the topic exchange. The scenario is something like this:
Service A in my application wants to send message of type appointments to service B and service C via an exchange named as: appointments-request based on different use case scenarios such as book, cancel, update etc.
So messages with a key appointments.book.B or appointments.cancel.B should go to consumer queue group appointments.B
messages with a key appointments.book.C or appointments.cancel.C should go to consumer queue group appointments.C
How to achieve this successfully?
Configuration of Producer Service:
spring.cloud.stream.bindings.output.destination=appointments-request
spring.cloud.stream.bindings.input.destination=appointments-reply
spring.cloud.stream.rabbit.bindings.output.producer.exchangeType=topic
spring.cloud.stream.rabbit.bindings.output.producer.routingKeyExpression=
appointments.#.#
Configuration of Consumer Service B:
spring.cloud.stream.rabbit.bindings.input.consumer.exchangeType=direct
spring.cloud.stream.rabbit.bindings.input.consumer.group=
appointments.docmgmt
spring.cloud.stream.rabbit.bindings.input.consumer.bindingRoutingKey=
appointments.docmgmt
spring.cloud.stream.rabbit.bindings.input.consumer.routingKeyExpression=
appointments.#.docmgmt
Producer Service A has the below method to set routing key
public boolean send(AppointmentEvent appointmentEvent)
{
logger.info("Sending event {} ",appointmentEvent);
return this.source.output().
send(MessageBuilder.withPayload(appointmentEvent).
setHeader(SimpMessageHeaderAccessor.DESTINATION_HEADER,
"appointments.book.docmgmt").build());
}
My communication between services is not working.
appointments.#.#
You can't use wildcards on the producer side.
You need something like
spring.cloud.stream.rabbit.bindings.output.producer.routingKeyExpression=headers['routingKey']
And then the producer sets the routingKey header to the desired value for each message.
You shouldn't really use the Simp headers; that is for STOMP; use your own header.

Spring AMQP- How does i retry/re-queue message from DLX queue to original queue?

i am trying to implement below scenario in my application
Exachange e1 -> Queue q1
DLX exchange e2 -> Queue q2
Also i have mentioned DLE and DLK in queue-q1 then message moving to queue-q2 on rejection/failure/timeout.
But how does i resend/retry message from queue-q2 to original queue-q1?
You can do that manually in your application after some analyze and filtering logic. Or you can make some TTL on that queue-q2 to let not consumed messages to be expired. And you also need to specify in this queue a x-dead-letter-exchange as a name for the Exachange e1 for desired recycling.
See more info yin this article:
Create the dead letter exchange, which is just a normal exchange with a special name
Create a retry_message queue and have all messages published to the dead letter exchange route here
When you setup the retry_message queue, be sure to default the following parameter values of the queue
x-message-ttl: 30000 – This will set a ttl on any message published to the queue. When the ttl expires, the message will be republished to the exchange specified in the x-dead-letter-exchange parameter.
x-dead-letter-exchange: original_exchange_name – This is where the message will get republished to once the message ttl expires. We normally want this be the name of the exchange where the message was originally published.

How to make rabbitmq to refuses messages when a queue is full?

I have a http server which receives some messages and must reply 200 when a message is successfully stored in a queue and 500 is the message is not added to the queue.
I would like rabbitmq to refuse my messages when the queue reach a size limit.
How can I do it?
actually you can't configure RabbitMq is such a way. but you may programatically check queue size like:
`DeclareOk queueOkStatus = channel.queueDeclare(queueOutputName, true, false, false, null);
if(queueOkStatus.getMessageCount()==0){//your logic here}`
but be careful, because this method returns number of non-acked messages in queue.
If you want to be aware of this , you can check Q count before inserting. It sends request on the same channel. Asserting Q returns messageCount which is Number of 'Ready' Messages. Note : This does not include the messages in unAcknowledged state.
If you do not wish to be aware of the Q length, then as specified in 1st comment of the question:
x-max-length :
How many (ready) messages a queue can contain before it starts to drop them from its head.
(Sets the "x-max-length" argument.)

get queuename on activemq server to push message

I have got 10 queues on activemq server.
I have producer which want to push messages on one of the queue (the producer will select the queue randomly run time to put message on queue), how can I pass destination name in createProducer method.
I understand that I need to pass an object of type Destination. the producer would know the queues name on the server. Is it possible to pass (or convert) a string to Destination object type and pass that to createproducer method.
Thanks
If I understand your problem correctly;
If you're running Java and have a valid session, you could use Session.createQueue();
// Create a Destination using the queue name
Destination destination = session.createQueue("queue name");
// Create a MessageProducer from the Session to the Queue
MessageProducer producer = session.createProducer(destination);
Here is a complete example of doing this at the Apache site.

JMS message priority not working on Message

I need to set message priority so that High priority messages are consumed before Low priority messages by Receivers.
First I tried with message.setJMSPriority() method to set the priority but it was not working in HornetQ and ActiveMQ so finally I set the priority of the Message Producer using setPriority() method and it works fine now.
Why isn't Messsge.setJMSPriority() working in any of the JMS vendor implementations and why do we need to set the priority of the Producer not the message itself to set the priority of the message? What is the use of Messsge.setJMSPriority() method then?
Any suggestion or comment is appreciated.
To answer this question all you need to do is read the API docs for the setJMSPriority method and it tells you why. Here's the relevant text.
Sets the priority level for this message.
JMS providers set this field when a message is sent. This method can be used to change the value for a message that has been received.
The JMS Provider (ActiveMQ, HornetMQ, etc) set the priority in the producer on send to either the default value of 4, or to whatever value you've set the producer to use, so setting the value before send on the message itself won't have any effect.
The following will not work:
msg.setJMSPriority(9); // Not working!
In this code, the message priority is set to 9, indicating this is a high-priority message.
However, when the message is sent, the message will have a priority of 4 (normal
priority). The reason? Like the message expiration, the JMS provider will look at the
message priority property on the sender, or on the send(..) invocation, and then invoke the setJMSPriority on the message method prior
to placing the message on the queue. Since the default message priority is 4 (normal
priority), the message priority will not be set to a high priority message, as the developer had originally intended.
Like the message expiration, there are two ways of setting the message priority: you
can invoke the setPriority() method on the MessageProducer (QueueSender or Topic
Publisher) or set the message priority when sending the message:
//set the default message priority for all messages to 9 (high)
QueueSender qSender = qSession.createSender(requestQ);
qSender.setPriority(9);
qSender.send(msg1);
//this message is low priority
qSender.send(msg2, DeliveryMode.PERSISTENT, 1, 30000);
In this example, msg1 will be sent with a priority of 9 (high priority), whereas msg2 will
be sent with a priority of 1 (low priority).
This is a JMS Specification requirement.
You should change the priority on the Message Producer.
You can read JmsTemplate http://static.springsource.org/spring/docs/3.0.6.RELEASE/spring-framework-reference/html/jms.html
Some JMS providers allow the setting of default QOS values administratively through the configuration of the ConnectionFactory.
Check isExplicitQosEnabled property.