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From Kostas Kloudas <k.klou...@data-artisans.com>
Subject Re: CEP timeout occurs even for a successful match when using followedBy
Date Sat, 29 Apr 2017 16:39:23 GMT
Hi Moiz,

The skip-till-next is a big change and backporting it does not seem feasible. 
Also this would require more general changes to the 1.2 to make it compatible with the previous
1.2 versions.

If you want you can already use the 1.3 version by downloading the master branch and writing
your 
use-case against that. The changes until the final release are going to be minor hopefully
and we can
always help you adjust your program accordingly.

Hope this helps,
Kostas

> On Apr 29, 2017, at 6:23 PM, Moiz S Jinia <moiz.jinia@gmail.com> wrote:
> 
> Oh ok thats a bit far off. Is there any chance of a backport of https://issues.apache.org/jira/browse/FLINK-6208
<https://issues.apache.org/jira/browse/FLINK-6208> to the 1.2 branch? I require the
SKIP_TILL_NEXT behaviour for a production use case that we want to use Flink for.
> 
> Moiz
> 
> On Sat, Apr 29, 2017 at 9:49 PM, Kostas Kloudas <k.kloudas@data-artisans.com <mailto:k.kloudas@data-artisans.com>>
wrote:
> The 1.3 is scheduled for the beginning of June.
> 
> Cheers,
> Kostas
> 
>> On Apr 29, 2017, at 6:16 PM, Moiz S Jinia <moiz.jinia@gmail.com <mailto:moiz.jinia@gmail.com>>
wrote:
>> 
>> Thanks Dawid! 
>> Yes thats what i was expecting. I'll give it a try.
>> 
>> When do you expect 1.3.0 stable to be out?
>> 
>> Moiz
>> 
>> On Sat, Apr 29, 2017 at 9:20 PM, Dawid Wysakowicz <wysakowicz.dawid@gmail.com
<mailto:wysakowicz.dawid@gmail.com>> wrote:
>> Hi,
>> 
>> This is an expected behaviour. After the "ar" event there still may occur other "ar"
event that will also trigger a match.
>> To be more generic in all versions prior to 1.3.0 there are two different consuming
strategies:
>> STRICT (the next operator) - that accepts only if the event occurs directly after
the previous 
>> SKIP TILL ANY (the followedBy operator) - it accepts any matching event following
event if there were already an event that matched this pattern
>> Because after "ni" event we could match with some other "ar" events, the match is
timeouted after 5 seconds.
>> 
>> In FLINK-6208 <https://issues.apache.org/jira/browse/FLINK-6208> we introduced
third consuming strategy:
>> SKIP TILL NEXT(this is the strategy for followedBy right now) - the event does not
have to occur directly after the previous one but only one event can be matched
>> and you can still use SKIP TILL ANY by using followedByAny. I believe the SKIP TILL
NEXT strategy is the one you expected. 
>> You can check it on master branch. We did introduce lots of new features and bugfixes
to CEP for 1.3.0 version so any comments,
>> tests or suggestions are welcome.
>> 
>> 
>> Z pozdrowieniami! / Cheers!
>> 
>> Dawid Wysakowicz
>> Data/Software Engineer
>> Skype: dawid_wys | Twitter: @OneMoreCoder
>>  <http://getindata.com/>
>> 
>> 2017-04-29 12:14 GMT+02:00 Moiz S Jinia <moiz.jinia@gmail.com <mailto:moiz.jinia@gmail.com>>:
>> When using "next", this pattern works fine for the both a match as well as a timeout:
>> 
>> Pattern<Event, Event> pattern = Pattern.<Event>begin("start")
>>         .where(evt -> evt.value.equals("ni"))
>>         .next("last").where(evt -> evt.value.equals("ar")).within(Time.seconds(5));
>> 
>> 1. "ni" then "ar" within 5 seconds - triggers match
>> 2. "ni" then no "ar" within 5 seconds - triggers timeout
>> 
>> But with "followedBy", this does not behave as expected:
>> 
>> Pattern<Event, Event> pattern = Pattern.<Event>begin("start")
>>         .where(evt -> evt.value.equals("ni"))
>>         .followedBy("last").where(evt -> evt.value.equals("ar")).within(Time.seconds(5));
>> 
>> "ni" then "ar" within 5 seconds - triggers match and also triggers timeout.
>> 
>> Why is the timeout triggered when using followedBy (when there is a match)?
>> 
>> Version - 1.1.5.
>> 
>> 
> 
> 


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