You are welcome!
> On Jun 3, 2016, at 4:40 PM, Igor Berman <[email protected]> wrote:
>
> thanks Kosta
>
> On 3 June 2016 at 16:47, Kostas Kloudas <[email protected]
> <mailto:[email protected]>> wrote:
> Hi Igor,
>
> To handle late events in Flink you would have to implement you own custom
> trigger.
>
> To see a relatively more complex example of such a trigger and how to
> implement it,
> you can have a look at this implementation:
> https://github.com/dataArtisans/beam_comp/blob/master/src/main/java/com/dataartisans/beam_comparison/customTriggers/EventTimeTriggerWithEarlyAndLateFiring.java
>
> <https://github.com/dataArtisans/beam_comp/blob/master/src/main/java/com/dataartisans/beam_comparison/customTriggers/EventTimeTriggerWithEarlyAndLateFiring.java>
>
> Which implements the trigger described in this article (before the
> conclusions section)
> http://data-artisans.com/why-apache-beam/
> <http://data-artisans.com/why-apache-beam/>
>
> Thanks,
> Kostas
>
>> On Jun 3, 2016, at 2:55 PM, Igor Berman <[email protected]
>> <mailto:[email protected]>> wrote:
>>
>> Hi
>>
>> according to presentation of Tyler Akidau
>> https://docs.google.com/presentation/d/13YZy2trPugC8Zr9M8_TfSApSCZBGUDZdzi-WUz95JJw/present
>>
>> <https://docs.google.com/presentation/d/13YZy2trPugC8Zr9M8_TfSApSCZBGUDZdzi-WUz95JJw/present>
>> Flink supports late arrivals for window processing, while I've seen several
>> question in the userlist regarding late arrivals and answer was - sort of
>> "not for all usecases"
>> Can somebody clarify?
>>
>> The interesting case for me - I have event processing time, while I want to
>> aggregate by tumbling window. The events come from kafka and might be late.
>> Currently we define lateness threshold with watermark (e.g. 5 mins)
>>
>> After window triggers I want to save aggregated result at some persistent
>> storage(redis/hbase) with start timestamp of window
>>
>> After this grace period - if I understand correctly - any event won't be
>> aggregated into existing window, but rather the trigger will call aggregated
>> function with only 1 element inside(the late one)
>>
>> so if my window method saves into persistent storage - it will override
>> aggregated result with new one that has only 1 element inside
>>
>> what I want to achieve - is that late arrival will trigger window method
>> with all elements (late + all other) so that aggregated result will be
>> complete
>>
>> you can think about use case of page visits counts per minute, while due to
>> some problems page visit events might arrive late
>>
>> thanks in advance
>>
>>
>>
>
>
