Hello,
I am trying to create an application that would use a message queue that
is consumed by multiple consumers running concurrently but would still
maintain the order of message processing by a certain ID.
For example, I have a set of messages added to a queue:
ID1-M1
ID1-M2
ID2-M1
ID3-M1
ID2-M2
ID3-M2
I need the Messages coming from ID1 get consumed by Consumer1, ID2 to
Consumer2, and ID3 to Consumer3, that maintains order such as Consumer1
will process ID1-M1 and then ID1-M2, Consumer 2 process ID2-M1 and then
ID2-M2, and Consumer3 process ID3-M1 and then ID3-M2.
I also like to have the Consumers come from a ConsumerPool so that if a
consumer is done processing with the messages, it will go back to the
pool and become available for other Messages owned by another ID. I also
like to have the pool a behavior that would create a new consumer in the
pool if a consumer dies so that a fix number of consumer is available
from the pool.
I saw in the documentation that the Message Group, I think, fits into
the requirement perfectly. Process messages asynchronous, maintain
message order, and failover feature.
Unfortunately, I was not able to understand completely how to do it. I
understand that the producer needs to set a property "JMSXGroupID" to
identify which group the message will get associated and consumed by a
single consumer. What I don't understand is how the broker will select
which consumer to pass the message to? Even more, where will the
consumers come from? Do I need to create, for example, 20 consumers and
subscribe them all to the broker? What if the consumer one by one dies,
can the broker automatically recreate all 20 consumers?
It would be greatly appreciated if anybody can write a simple code that
would show how consumers get subscribed to the broker and have an
explanation that my requirement would really fit into Message Group. If
this is not possible through Message Group, any suggestions on how to
implement this?
Thanks in advance!
-don
