Hi Hans,

Going through the log files I realized it had something to do with
multithreaded executions. I tried using the  Beam Kafka Consumer but the
issue is it only supports AVRO. I need to consume json messages

Thanks
Mono

On Fri, Apr 22, 2022 at 12:21 AM Hans Van Akelyen <
[email protected]> wrote:

> Hi Monajit,
>
> This is the auto scaling nature of Flink fighting against the requirement
> of having a single threaded pipeline for Kafka messages (as we need to know
> when messages are finished. When running on Flink the best solution would
> be to use the Beam Kafka Consumer.
>
> Another solution (but not yet tested here so not sure it will work) is to
> force it to a single thread by setting SINGLE_BEAM in the "number of
> copies".
> More information about this can be found on our documentation pages [1]
>
> Kind regards,
> Hans
>
> [1]
> https://hop.apache.org/manual/latest/pipeline/beam/getting-started-with-beam.html
>
> On Fri, 22 Apr 2022 at 06:50, monajit choudhury <[email protected]>
> wrote:
>
>> Hi,
>>
>> I am trying to test a simple kafka consumer using Apache Hop v1.2. When I
>> run the pipeline using the local runner, it works fine. But if I run it
>> using the flink runner I get the following error
>>
>> You can only have one copy of the injector transform 'output' to accept
>> the Kafka messages
>>
>> I have tried debugging the Hop code and looks like the root cause is the
>> initSubPipeline() method being invoked multiple times while using the Flink
>> runner. That's not the case when I use the local runner. Am I missing
>> something here?
>>
>>
>> Thanks
>>
>> Monajit Choudhury
>>
>> Linkedin <https://www.linkedin.com/in/monajit-choudhury-b1409a2/>
>>
>

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