I think we should not allow negative values, and today it seems that this is not checked against.
In fact, it should be a one-liner fix in the `config.define` function call to constraint its possible value range. Would you like to contribute a PR? Guozhang On Fri, Oct 12, 2018 at 10:56 PM Tomoyuki Saito <aocch...@gmail.com> wrote: > Hello Guozhang, > > Thank you for your reply. > > > setting to "0" will actually mean to commit every time. > > Hum, I somehow misunderstood the code. Now I understand that is true. > > > You should actually set it to Long.MAX_VALUE to indicate "not commit > regularly by intervals" > > I see. I'd consider taking that approach! > > > Another question just from curiosity: > > From looking at code, setting `commit.interval.ms` to a negative value can > also indicate "not commit regularly by intervals." In other words, it has > the same effect as setting it to Long.MAX_VALUE. > Is this true? > > The implication of setting the property to a negative value is > undocumented, so I'm thinking setting it to Long.MAX_VALUE is preferable. > > Thank you. > Tomoyuki > > On Sat, Oct 13, 2018 at 1:48 AM Guozhang Wang <wangg...@gmail.com> wrote: > > > Hello Tomoyuki, > > > > 1. Seems a good use case for Streams. > > 2. You should actually set it to Long.MAX_VALUE to indicate "not commit > > regularly by intervals", setting to "0" will actually mean to commit > every > > time. Then you can leverage on ProcessorContext.commit() to manually > commit > > after the batch is done. > > > > > > Guozhang > > > > > > > > > > On Wed, Oct 10, 2018 at 11:15 PM, Tomoyuki Saito <aocch...@gmail.com> > > wrote: > > > > > Hi, > > > > > > I'm exploring whether it is possible to use Kafka Streams for batch > > > processing with at-least-once semantics. > > > > > > What I want to do is to insert records in an external storage in bulk, > > and > > > execute offset-commit after the bulk insertion to achieve at-least-once > > > semantics. > > > A processing topology can be very simple like: > > > ``` > > > TopologyBuilder builder = new TopologyBuilder(); > > > builder.addSource("source", "topic"); > > > builder.addProcessor("processor", processorSupplier, "source"); > > > new KafkaStreams(builder, streamsConfig); > > > ``` > > > > > > My questions are: > > > > > > 1. Could you suggest how to achieve that? Can it be better to use > > > KafkaConsumer instead of KafkaStreams? > > > > > > 2. From my understanding, when setting StreamsConfig ` > commit.interval.ms > > ` > > > to 0, we can turn off offset-commit by KafkaStreams internal logic (in > > > StreamThread#maybeCommit), and control when to commit offsets with > > > `ProcessorContext#commit`. Is my understanding right? Any expected > issues > > > for this approach? > > > > > > Thank you, > > > Tomoyuki > > > > > > > > > > > -- > > -- Guozhang > > > -- -- Guozhang