events in a clustered environment with Apache Camel and MongoDB.

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Event Queue
Instance 'A'
Instance 'B'
Instance 'C'
Database
server cluster with queue

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E
E
E
Instances
producing
events...
...with the
same id
(e.g. 0815)
producing events...

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E
E
E
Instance 'C'
consumes the
first event
consuming first event...

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E
E
E
a cluster means multible consumers for a event
If there're trying
multible instances to
consume the same
event we're getting in
trouble.

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E
E
E
we have to track the cosumption over a database
To guarantee that an
event will be consumed
only once we have to
track the consumption
Is event with id
'0815' already
registered?

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E
E
E
the first incoming event will be registered
No, it's not
registered.
Ok register
it!

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E
E
E
all others with the same id will be found...
2. Yes!
1. '0815'
already
registered?

8. www.catify.com
E
E
...and rejected
E
Kick it!

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In the next part of this blog entry we show how
to implement this with camel in 5 minutes :)
http://www.catify.com/blog