If there are n-nodes in a Cluster and I am routing some messages to them, is there a way to track which message has been sent to which node from within the Cluster Router(RoundRobinPool or any other if available).
i.e After sending all the messages, at last, I need a list something like..
'message-1,4,7 has been sent to A-node',
'message-2,5,8 to B-node',
'message-3,6,9 to C-node' and so on.
Any help would be greatly appreciated.
Easiest way to get this information is to have the receiving actor on the other end of the router send an acknowledgement message back to the original sender and then log that on the sending side. You could also turn some of the logging tools for logging remote message sending on or off, but that will be verbose.
https://github.com/akkadotnet/akka.net/blob/dev/src/core/Akka.Remote/Configuration/Remote.conf#L125
Related
I am trying to use streams with redis using Reddison lib. I am using code StreamReadGroupArgs.neverDelivered() when receiving the messages. But if I don't ack it then the next time when readGroup is called it does not get those messages. The problem is that what if the node crashed or there was a glitch in network and I could not process those messages. Then even if I have not ack it I will not get those messages again. Is there a workaround for this or something else that I can do?
This is the correct behavior. Otherwise you will end up receiving redundant messages everytime.
Either you have to acknowledge or you have to explicitly ask redis to resend the messages which you have not acknowledged. For that StreamReadGroupArgs.neverDelivered() is not a correct option. Because it was already delivered. But you lost the message somehow.
Correct option for your use case is the below one which will send the messages which are not acknowledged.
StreamReadGroupArgs.greaterThan(new StreamMessageId(0))
I am using RabbitMQ to queue up all the messages and send the messages as SMS to respective consumers. I am using a Direct exchange and I have correctly created a binding to a queue with a routing key. The problem is, when I try to publish a message, I get some activity in the Message rates chart, but the message doesn't show up in the queue
Could certainly use some help here. I am sure the binding is done correctly.
Am I missing some other configuration?
I would recommend to "use specific exchanges", not sending message without specified exchange. I had same issue, when I published it to amq.direct or amq.fanout it worked as I wanted to.
If your configuration is correct, and you also have an active consumer that listens to that queue, I don't think anything is wrong. Doesn't those metrics depicts that the event was published and then delivered and acknowledged by the consumer ? So of course you won't have any queued events since it was consumed as soon as it was published.
It looks like the message is delivered to a consumer (as you can see in the chart). Remove the consumer and try to publish the message again, and you will see that it ends up in the queue instead.
In my case I was creating custom queue so I had to provide custom queue ID as a routing key.
I'm trying to use RabbitMQ in a more unconventional way (though at this point i can pick any other message queue implementation if needed)
I have one queue (I can have more if needed) that where customers are fetching N messages asynchronous. After they do their work I send the results from the client to the db.
I have two problems: first I don't want that they will work on the same message, second I want to grantee that I wont lose messages in case that my customer will close the browser or just stop working.
I looked at the documentation and saw the TTL which was perfect for me if I could alter that message that got timeout isn't going to be deleted but to move to another queue. can't find a way to alter this.
Moreover I looked at the confirmation option which in the first glance looked what I wanted,that mechanism is working like this: when the consumer gets a message he send confirmation to queue, I thought I can delay this confirm and send it when the work is done on the client side.
my problem was that I can't program the queue that if any message didn't get confirm then return it to the queue (or to another).
I also find how to do a scheduled message but it didn't help either because I don't want that the message will be inserted to the queue in five min,I want that when a customer will receive a message it will be locked in the queue for 5 min until confirm to delete is set otherwise return it to the queue.
Can I do temporary queue that enables my mechanism?
If someone can help with one of the problems or suggest another architecture or option to do it in another MQ it would be great.
Resources:
confirmation:
http://www.rabbitmq.com/blog/2011/02/10/introducing-publisher-confirms/
post about locks but his problem was a batcher component:
Locks and batch fetch messages with RabbitMq
TTL:
https://www.rabbitmq.com/ttl.html
Schedule a message:
https://www.rabbitmq.com/blog/2015/04/16/scheduling-messages-with-rabbitmq/
my problem was that I can't program the queue that if any message
didnt get confirm then return it to the queue (or to another).
RabbitMQ does this anyhow, so all you have to do is switch off the auto-ack flag, you figured this out
I thought I can delay this confirm and send it when the work is done
on the client side.
so just send the ACK once you've finished with processing the message.
All the unacknowledged messages remain in the queue and are re-delivered to next consumer (or the same one when it's up again, depending on your setup)
I have this issue, I want to know my rabbit is working great.
I am not gonna send the message, so, Im not 100% sure is being sent correctly. But the problem is this.
After all is configured and all....
I see at the RabbitMQ web manager
And when I supposedly send a message the I see activity on the "message rates" chart but nothing at the "queued messages" .
I frankly dont know whats going on, is it too fast that doesnt need to queue the messages? Or something is misconfigured?
Any idea of the difference?
Thanks.
In case RabbitMQ receive non-routable message it drop it. So while message was received, it was not queued.
You may configure Alternate Exchanges to catch such messages.
In my case,
Situation1:
when my Exchange in rabbitTemplate.convertAndSend was not set properly -- the message was not sent to the correct queue -- the Queued messages was empty all time.
however, Message rates is not zero, it does show there are message get sent.
Which correspond to what the other answer is saying:
In case RabbitMQ receive non-routable message it drop it.
Situation2:
when my Exchange in rabbitTemplate.convertAndSend was indeed set properly -- the message was sent to the correct queue -- the Queued messages was queuing up the message.
Everything seems fine.
Situation3:
(continue from Situation2)
And now, I turn on the receiver service which has the #RabbitListener.
The Queued messages immediately drops down to 0, and never goes up again.
But the transporting of messages is still working fine.
Situation4:
(continue from Situation2)
And now, I change the receiver service to use the rabbitTemplate.receiveAndConvert.
Which I manually receive the message from the queue every 2s by using a loop.
(message is also sent from sender service every 2s by using a loop, same as the situations before.)
Now, the Queued messages stays at constant -- a straight line
(depends on how many message you have queued up, in my case 1, before the receiver service is up, then it stays at 1).
Conclusion:
I suspect that, when the message is consumed too fast, the Queued messages will just show 0.
Which correspond to what the OP is saying:
is it too fast that doesnt need to queue the messages?
(or, I could screw up some setting in RabbitMQ and led to wrong conclusion. I dont think so, but idk, I am not familiar with RabbitMQ.)
When using ActiveMQ, some problems troubles me:
1. When broker crashed or stopped, messages from sender will be lost(I set timeout, because the sender have others to do).
2. Consumer receives all messages from broker, but how i know the consumer received all messages(zero lost).
3. If message is lost, i want to know it immediately.
In production, I want to monitor the activemq, and know which message is lost.
Can anyone give me a favor?
you can implement a listener that is called as soon as you producers/consumers lose contact with broker.
http://activemq.apache.org/maven/5.5.0/activemq-core/apidocs/org/apache/activemq/transport/TransportListener.html
If consumer crashes
use explicit ack: activemq.apache.org/should-i-use-transactions.html
you can use persistent messages to avoid losing messages if broker crashes:
activemq.apache.org/what-is-the-difference-between-persistent-and-non-persistent-delivery.html