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[Eric Windisch <eric@xxxxxxxxxxxxxxxx>]

> 
> The only problem is, it breaks backward compatibility a bit: my patch
> assumes you have a flag "rabbit_addresses" which should look like
> "rmq-host1:5672,rmq-host2:5672" instead of the prior rabbit_host and
> rabbit_port flags.
> 
> Guys, can you advise on a way to do this without being ugly and
> without breaking compatibility?
> 
> 

One way would to use the matchmaker which I introduced to solve a similar problem with the ZeroMQ driver. The matchmaker is a client-side emulation of bindings/exchanges for mapping topic keys to an array of topic/host pairs.

You would query the matchmaker with a topic (key) and it would return tuples in the form of:
 ("topic", broker_ip)

In the ZeroMQ case, the "broker_ip" is always the peer, but with RabbitMQ, this would be one (or more) of your selected brokers.  Generally, you would return multiple brokers when you're doing fanout messaging.


Regards,
Eric Windisch