Thomas Crowley created KAFKA-8846:
-------------------------------------

             Summary: Unexpected results joining a KStream to a KTable after 
repartitioning 
                 Key: KAFKA-8846
                 URL: https://issues.apache.org/jira/browse/KAFKA-8846
             Project: Kafka
          Issue Type: Bug
          Components: streams
    Affects Versions: 2.3.0
            Reporter: Thomas Crowley


We seem to have come across a bug with Kafka Streams (or at least unexpected 
behavior) when joining a KStream to a KTable after re-partitioning our data 
(via `selectKey`)

Our use case is as follows: we want to aggregate some values and join them back 
onto the original message, so that we emit the original message, joined with 
the current value of the aggregation at the current point in time.

Currently, without re-partitioning, we get the correct behavior as expected, 
but rekeying the input of the stream gives us incorrect results.

What's stranger, is that the `TestTopologyDriver` gives us the correct/expected 
results in our re-partitioned topology.


Apologies if Clojure is foreign to anyone, but I have an example of the 
problematic topology here:
https://github.com/VerrencyOpenSource/repartition-bug/blob/master/src/repartition_bug/with_repartition.clj#L27

If you have `lein` installed on your machine, I have instructions on how you 
can run the above topology against both the test topology driver and a Kafka 
cluster: 
https://github.com/VerrencyOpenSource/repartition-bug 





--
This message was sent by Atlassian Jira
(v8.3.2#803003)

Reply via email to