Update on this. Modifying the state store on another thread actually doesn’t
work. I receive the error
java.lang.IllegalStateException: This should not happen as offset() should only
be called while a record is processed
at
org.apache.kafka.streams.processor.internals.AbstractProcessorContext.offset(AbstractProcessorContext.java:138)
at
org.apache.kafka.streams.state.internals.CachingKeyValueStore.put(CachingKeyValueStore.java:203)
at
org.apache.kafka.streams.state.internals.CachingKeyValueStore.put(CachingKeyValueStore.java:198)
So is there a way to do this?
> On 25 Aug 2017, at 9:57 am, Eli Jordan <elias.k.jor...@gmail.com> wrote:
>
> Hi
>
> I have a kafka streams application, that uses a couple of stateful (i.e.
> using key value stores) custom transformer implementations.
>
> I'm aware that the scheduling of the punctuate method is based on stream
> time. However, for my use case, this is not what I want, I need wallclock
> scheduling.
>
> My question is, what is the recommended way to achieve this, until KIP138
> provides first class support for wallclock punctuate?
>
> At the moment, I schedule a task to run using ScheduledExecutorService.
> However, I'm uncertain whether it is safe to access and modify a
> KeyValueStore from a non kafka streams thread. Is this a safe approach, or
> will there be problems?
>
> Thanks
> Eli
