How do I get old messages from RabbitMQ?

Question

I'm publishing RabbitMQ messages using Bunny (Ruby) like this:

x.publish("Message !"+n.to_s, :routing_key => 'mychannel')

and subscribing like this:

    ch   = conn.create_channel
x    = ch.topic('fling',durable: true)
q    = ch.queue("")
q.bind(x, :routing_key => 'mychannel')


puts "Waiting for messages."
q.subscribe( :block => true) do |delivery_info, properties, body|
puts " [x] Received #{body}, message properties are #{properties.inspect}"

Once I start the subscriber, it immediately receives any messages which are sent. However, if I send messages without starting the subscriber, they aren't received when I start the subscriber (whether the sender is still pushing messages, or not).

Is it possible to go back through the queue and receive messages that were sent in the past, when no subscribers were listening?

score 9 · Answer 1 · edited Nov 26 '15 at 03:10

9

You're making a new queue each time you start the consumer! So when you restart the consumer, the new queue gets new messages, but doesn't have previous ones.

Do this:

q    = ch.queue("myqueue",durable: true)

instead of this:

q    = ch.queue("")

Then, as soon as you restart the consumer, it will immediately get all backed-up messages as fast as it can.

edited Nov 26 '15 at 03:10

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answered Nov 05 '15 at 14:02

Louise

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How long duration does RabbitMQ do back-up the messages? – syko Jun 29 '16 at 19:03
I don't understand what you mean by "back up." – Louise Jun 30 '16 at 11:49
What was the meaning of 'backed-up messages' you used then? – syko Jun 30 '16 at 13:45
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Backed-up messages means messages that are delayed. Are you asking "how long does RabbitMQ delay the messages?" It delays them until you collect them! How long is a piece of string... – Louise Jul 01 '16 at 11:52

score 0 · Answer 2 · answered Dec 13 '21 at 06:01

0

Queue has to be parameter called durable its never losses

ch.queue(queue, {
       durable: true
     });
instead 
q    = ch.queue("")

answered Dec 13 '21 at 06:01

Krish Chary

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Your answer could be improved with additional supporting information. Please [edit] to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers [in the help center](/help/how-to-answer). – Community Dec 13 '21 at 07:21

How do I get old messages from RabbitMQ?

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