[openamq-dev] message duplicates

[Dmitri Tsyganov]

Hello,

I cam across interesting problem, possibly a bug.
Here is the scenario.

I have a feed client that sends messages  to open amq with routing key 
TEST.NASDAQ.UTP.TRADE

I have clients that subscribe to amq.topic exchange with different, 
sometimes overlapping variants of the routing key.

For example, one client may subscribe with TEST.*.*.*, another with 
*.NASDAQ.*.*.* etc.

Problem 1:
If clients uses the same queue name, they start receiving duplicate 
(sometimes 3, 4 etc) messages .
You can probably do this with just one client and try to bind the same 
queue to overlapping routing key, I think you should see multiple copies 
of the same message coming to your client.

I think because of that, there is interesting side-effect when I am 
using mta clustering configuration.

Problem 2:
I have two amq_serevers - one is "master" - receives all the feeds, and 
one is "slave" - serves all the clients. The slave is peering with the 
master via mta configuration option 1 - subscriber.
When my clients subscribe to a slave (amq.topic exchange) with 
overlapping routing keys (note that queue names may be, and usually are, 
unique!) they receives multiple copies of the messages that match their 
subscription rules. This is probably because "master" amq server sends 
multiple copies of the same message to the "slave".

Thank you,

Dmitri