I think now it’s not easily possible, however it might be a valid suggestion to add `OnTimerContext#getCurrentKey()` method.
Besides using ValueState as you discussed before, as a some kind of a walk around you could copy and modify KeyedProcessOperator to suits your needs, but this would be more complicated. Piotrek > On 4 Feb 2018, at 20:36, Ken Krugler <kkrugler_li...@transpac.com> wrote: > > Hi Jürgen, > > That makes sense to me. > > Anyone from the Flink team want to comment on (a) if there is a way to get > the current key in the timer callback without using an explicit ValueState > that’s maintained in the processElement() method, and (b) if not, whether > that could be added to the context? > > Thanks, > > — Ken > > >> On Feb 4, 2018, at 6:14 AM, Jürgen Thomann <juergen.thom...@innogames.com >> <mailto:juergen.thom...@innogames.com>> wrote: >> >> Hi Ken, >> >> thanks for your answer. You're right and I'm doing it already that way. I >> just hoped that I could avoid the ValueState (I'm using a MapState as well >> already, which does not store the key) and get the key from the provided >> Context of the ProcessFunction. This would avoid having the ValueState and >> setting it in the processElement just to know the key in the onTimer >> function. >> In the current way I have to check the ValueState for every element if the >> key is already set or just set it every time again the processElement method >> is invoked. >> >> Best, >> Jürgen >> >> On 02.02.2018 18:37, Ken Krugler wrote: >>> Hi Jürgen, >>> >>>> On Feb 2, 2018, at 6:24 AM, Jürgen Thomann <juergen.thom...@innogames.com >>>> <mailto:juergen.thom...@innogames.com>> wrote: >>>> >>>> Hi, >>>> >>>> I'm currently using a ProcessFunction after a keyBy() and can't find a way >>>> to get the key. >>> >>> Doesn’t your keyBy() take a field (position, or name) to use as the key? >>> >>> So then that same field contains the key in the >>> ProcessFunction.processElement(in, …) parameter, yes? >>> >>>> I'm currently storing it in a ValueState<String> within processElement >>> >>> If you’re using a ValueState, then there’s one of those for each unique >>> key, not one for the operation. >>> >>> I.e. the ValueState for key = “one” is separate from the ValueState for key >>> = “two”. >>> >>> You typically store the key in the state so it’s accessible in the onTimer >>> method. >>> >>>> and set it all the time, so that I can access it in onTimer(). Is there a >>>> better way to get the key? We are using Flink 1.3 at the moment. >>> >>> The ValueState (what you used in processElement) that you’re accessing in >>> the onTimer() method is also scoped by the current key. >>> >>> So assuming you stored the key in the state inside of your processElement() >>> call, then you should have everything you need. >>> >>> — Ken >>> >>> PS - Check out >>> https://www.slideshare.net/dataArtisans/apache-flink-training-datastream-api-processfunction >>> >>> <https://www.slideshare.net/dataArtisans/apache-flink-training-datastream-api-processfunction> > -------------------------- > Ken Krugler > http://www.scaleunlimited.com <http://www.scaleunlimited.com/> > custom big data solutions & training > Hadoop, Cascading, Cassandra & Solr
