Re: kafka stream - sliding window - getting unexpected output

@Matthias J. Sax / All

Have added below line :

> .suppress(Suppressed.untilWindowCloses(Suppressed.BufferConfig.unbounded()))
>
>

Here is the output : (for uuid (*2cbef750-325b-4a2f-ac39-b2c23fa0313f)*,
expecting single output but that is not the case here. Which 1 is the final
output from those 2 rows for the same uuid ?

[KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=1, sum=10.0,
> strTime=2022-05-19 11:48:08.128, uuid=fb6bea5f-8fd0-4c03-8df3-aaf392f04a5a)

[KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=2, sum=20.0,
> strTime=2022-05-19 11:48:10.328, uuid=b4ab837f-b10a-452d-a663-719215d2992f)
> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=3, sum=30.0,
> strTime=2022-05-19 11:48:12.527, uuid=8fa1b621-c967-4770-9f85-9fd84999c97c)
> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=4, sum=40.0,
> strTime=2022-05-19 11:48:14.726, uuid=1fc21253-7859-45ef-969e-82ed596c4fa0)
> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=5, sum=50.0,
> strTime=2022-05-19 11:48:16.925, uuid=
> *2cbef750-325b-4a2f-ac39-b2c23fa0313f)*
> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=4, sum=40.0,
> strTime=2022-05-19 11:48:16.925, uuid=
> *2cbef750-325b-4a2f-ac39-b2c23fa0313f*)
> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=5, sum=50.0,
> strTime=2022-05-19 11:48:19.124, uuid=8f72454c-ec02-42c1-84e1-bcf262db436f)
> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=4, sum=40.0,
> strTime=2022-05-19 11:48:19.124, uuid=8f72454c-ec02-42c1-84e1-bcf262db436f)
> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=5, sum=50.0,
> strTime=2022-05-19 11:48:21.322, uuid=e4e73232-dbd4-45b4-aae9-f3bd2c6e54b4)
> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=4, sum=40.0,
> strTime=2022-05-19 11:48:21.322, uuid=e4e73232-dbd4-45b4-aae9-f3bd2c6e54b4)
> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=5, sum=50.0,
> strTime=2022-05-19 11:48:23.522, uuid=fc49906e-54d0-4e80-b394-3ebaf6e74eaa)
> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=4, sum=40.0,
> strTime=2022-05-19 11:48:23.522, uuid=fc49906e-54d0-4e80-b394-3ebaf6e74eaa)
> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=5, sum=50.0,
> strTime=2022-05-19 11:48:25.721, uuid=fbe62fa4-e7c4-437f-b976-0bb7ae0c4390)


On Wed, May 18, 2022 at 10:21 PM Matthias J. Sax <mjsax@apache.org> wrote:

> Emitting intermediate result is by-design.
>
> If you don't want to get intermediate result, you can add `suppress()`
> after the aggregation and configure it to only "emit on window close".
>
> -Matthias
>
> On 5/17/22 3:20 AM, Shankar Mane wrote:
> > Hi All,
> >
> > Our use case is to use sliding window. (for e.g. at any point, whenever
> >> user performs any actions at time [ t1 ], we would like to see his
> activity
> >> in [ t1 - last 24 hours]. Using this, to show the user some
> recommendations.
> >
> >
> >
> > -- I have code ready and it works without any errors.
> > -- aggregations happen as expected.
> > -- but the output generated is unexpected. As windows gets slides, i am
> > getting mixed output which includes intermediate aggregated records also
> > coming with final aggregated outputs.
> >
> > Could someone please help me here ? what can I do here to get ONLY final
> > aggregated output.
> >
> >
> > Code snippet :
> > ________________________________________________________________
> >
> >
> >
> > builder.stream(tempReadingTopic, Consumed.with(stringSerde, inputSerde))
> > .filter((k, v) -> v != null)
> > .map((k,v) -> KeyValue.pair(v.getUserId(), v))
> > //.through("slidingbykey",
> > Produced.with(Serdes.String(), inputSerde))
> > .groupByKey()
> >
> >
> .windowedBy(SlidingWindows.ofTimeDifferenceAndGrace(Duration.ofMillis(5000),
> > windowDuration))
> > .aggregate(OutputPojo::new, (k, tr, out) -> {
> > out.setUserId(tr.getUserId());
> > out.setCount(out.getCount() +1);
> > out.setSum(out.getSum() + tr.getInt4());
> > out.setUuid(tr.getUuid());
> >
> > out.setStrTime(TimestampLongToString.getTime(tr.getTimestamp()));
> > waitForMs(200); //added delay just for analysing
> output
> > return out;
> > }, Materialized.with(stringSerde, outputSerde))
> > .suppress(Suppressed.untilTimeLimit(windowDuration,
> > Suppressed.BufferConfig.unbounded()))
> > .toStream()
> > .map((Windowed<String> key, OutputPojo out) -> {
> > return new KeyValue<>(key.key(),out) ;
> > })
> > .print(Printed.toSysOut());
> > // .to(aveTempOutputTopic, Produced.with(stringSerde,
> > outputSerde))
> > ;
> >
> >
> >
> > ________________________________________________________________
> >
> >
> > Input data :
> >
> > for i in {1..10}; do sleep 1s;python3 del.py 1001 10;sleep 1s; done
> >> {'userId': '1001', 'timestamp': 1652781716234, 'int4': 10, 'uuid':
> >> '64f019ee-9cf4-427d-b4c9-f2b5f88820e1'}
> >> {'userId': '1001', 'timestamp': 1652781718436, 'int4': 10, 'uuid':
> >> 'cf173b3e-c34f-470a-ba15-ef648d0be8b9'}
> >> {'userId': '1001', 'timestamp': 1652781720634, 'int4': 10, 'uuid':
> >> '48d2b4ea-052d-42fa-a998-0216d928c034'}
> >> {'userId': '1001', 'timestamp': 1652781722832, 'int4': 10, 'uuid':
> >> '55a6c26c-3d2c-46f1-ab3c-04927f660cbe'}
> >> {'userId': '1001', 'timestamp': 1652781725029, 'int4': 10, 'uuid':
> >> 'dbfd8cee-565d-496b-b5a8-773ae64bc518'}
> >> {'userId': '1001', 'timestamp': 1652781727227, 'int4': 10, 'uuid':
> >> '135dc5cd-50cb-467b-9e63-300fdeedaf75'}
> >> {'userId': '1001', 'timestamp': 1652781729425, 'int4': 10, 'uuid':
> >> '66d8e3c7-8f63-43ca-acf1-e39619bf33a0'}
> >> {'userId': '1001', 'timestamp': 1652781731623, 'int4': 10, 'uuid':
> >> 'f037712b-42a5-4449-bcc2-cf6eafddf5ad'}
> >> {'userId': '1001', 'timestamp': 1652781733820, 'int4': 10, 'uuid':
> >> '7baa4254-b9da-43dc-bbb7-4caede578aeb'}
> >> {'userId': '1001', 'timestamp': 1652781736018, 'int4': 10, 'uuid':
> >> '16541989-f3ba-49f6-bd31-bf8a75ba8eac'}
> >
> >
> > ________________________________________________________________
> >
> >
> > Output (*Unexpected*) : below output is captured at each sliding window
> of
> > 1s duration (but input data is published at 2s of interval) :
> >
> > [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=3,
> sum=30.0,
> >> strTime=2022-05-17 15:31:28.263,
> >> uuid=966277fd-3bdc-45c2-aa6a-c9c0dbe89c34) ----> seems older UUID
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=1,
> sum=10.0,
> >> strTime=2022-05-17 15:31:28.263,
> uuid=966277fd-3bdc-45c2-aa6a-c9c0dbe89c34)
> >>
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=1,
> sum=10.0,
> >> strTime=2022-05-17 15:31:56.234,
> uuid=64f019ee-9cf4-427d-b4c9-f2b5f88820e1)
> >>
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=2,
> sum=20.0,
> >> strTime=2022-05-17 15:31:58.436,
> uuid=cf173b3e-c34f-470a-ba15-ef648d0be8b9)
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=2,
> sum=20.0,
> >> strTime=2022-05-17 15:32:00.634,
> uuid=48d2b4ea-052d-42fa-a998-0216d928c034)
> >>
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=3,
> sum=30.0,
> >> strTime=2022-05-17 15:32:00.634,
> uuid=48d2b4ea-052d-42fa-a998-0216d928c034)
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=2,
> sum=20.0,
> >> strTime=2022-05-17 15:32:02.832,
> uuid=55a6c26c-3d2c-46f1-ab3c-04927f660cbe)
> >>
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=3,
> sum=30.0,
> >> strTime=2022-05-17 15:32:02.832,
> uuid=55a6c26c-3d2c-46f1-ab3c-04927f660cbe)
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=2,
> sum=20.0,
> >> strTime=2022-05-17 15:32:05.029,
> uuid=dbfd8cee-565d-496b-b5a8-773ae64bc518)
> >>
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=3,
> sum=30.0,
> >> strTime=2022-05-17 15:32:05.029,
> uuid=dbfd8cee-565d-496b-b5a8-773ae64bc518)
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=2,
> sum=20.0,
> >> strTime=2022-05-17 15:32:07.227,
> uuid=135dc5cd-50cb-467b-9e63-300fdeedaf75)
> >>
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=3,
> sum=30.0,
> >> strTime=2022-05-17 15:32:07.227,
> uuid=135dc5cd-50cb-467b-9e63-300fdeedaf75)
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=2,
> sum=20.0,
> >> strTime=2022-05-17 15:32:09.425,
> uuid=66d8e3c7-8f63-43ca-acf1-e39619bf33a0)
> >>
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=3,
> sum=30.0,
> >> strTime=2022-05-17 15:32:09.425,
> uuid=66d8e3c7-8f63-43ca-acf1-e39619bf33a0)
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=2,
> sum=20.0,
> >> strTime=2022-05-17 15:32:11.623,
> uuid=f037712b-42a5-4449-bcc2-cf6eafddf5ad)
> >>
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=3,
> sum=30.0,
> >> strTime=2022-05-17 15:32:11.623,
> uuid=f037712b-42a5-4449-bcc2-cf6eafddf5ad)
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=2,
> sum=20.0,
> >> strTime=2022-05-17 15:32:13.820,
> uuid=7baa4254-b9da-43dc-bbb7-4caede578aeb)
> >>
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=3,
> sum=30.0,
> >> strTime=2022-05-17 15:32:13.820,
> uuid=7baa4254-b9da-43dc-bbb7-4caede578aeb)
> >> [KSTREAM-MAP-0000000011]: 1001, OutputPojo(userId=1001, count=2,
> sum=20.0,
> >> strTime=2022-05-17 15:32:16.018,
> uuid=16541989-f3ba-49f6-bd31-bf8a75ba8eac)
> >
> >
> > Regards,
> > Shankar
> >
>