[rabbitmq-discuss] Network failures recovery with RabbitMQ Javaclient

[Busoli, Simone]

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> Simone,
> 
> Thank you, this is exactly what I have in mind for publishers. For consumers
> there is a bunch of questions that need to be answered:
> 
> 1. Should recovering apps redeclare AMQP entities they use or use passive
> declares?

Currently I do, yes, although it somewhat defeats the purpose of durable entities which would fit well here. Currently I'm recreating everything from scratch when the connection goes down, and handle recovery of previous data that consumers may need at the application level. I'm however planning to start considering to use durable entities.

> 2. If I have 3 threads each with its own consumer (on separate channels, of
> course), how do I go about reopening their channels after AMQP connection
> is back up?

I'm dealing with this by having a single channel with one consumer which consumes from all the queues the application needs to read data from. What kind of limitation do you see in keeping it single threaded?

> 3. How do I detect that reconnection has succeeded?

In the .NET client when you Open the connection and no exception is thrown I think you can safely assume that the connection has been established.

> 
> So if I understand it correctly, your approach is to have one thread that
> consumes all messages and then dispatches them to different parts of the
> application, is my understanding correct?

Yes, correct. This entails that your application has to cope with messages being consumed by threads that the application does not know directly (as they belong to the messaging library), but I found it to be easier to do that than to consume from rabbit queues from multiple threads with multiple channels. Oh, I didn't specify it explicitly but I also use one single channel for publishing and one single channel for consuming.

> 
> MK
> 
> http://github.com/michaelklishin
> http://twitter.com/michaelklishin


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