Hi Harshvardhan, 1) Yes, ProcessWindowFunction extends AbstractRichFunction, through getRuntimeContext，you can access keyed state API. 2) ProcessWindowFunction has given you considerable flexibility, you can based on processing time / event time / timer / it's clear method / customized implementation, the specific design depends on your business logic, how long you need to save the cache.
Thanks, vino. Harshvardhan Agrawal <harshvardhan.ag...@gmail.com> 于2018年9月6日周四 下午10:10写道： > Hello, > > We have a Flink pipeline where we are windowing our data after a keyBy. > i.e. > myStream.keyBy().window().process(MyIncrementalAggregation(), > MyProcessFunction()). > > I have two questions about the above line of code: > 1) Does the state in the process window function qualify as KeyedState or > OperatorState? If operator state, can we access KeyedState from the Process > Window function? > 2) We also have certain reference information that we want to share across > all keys in the process window function. We are currently storing all that > info in a Guava cache. We want to be able to rehydrate the guava cache at > the beginning of each window by making an external rest call and clear the > cache at the end of that respective window. How can we enforce this > behaviour in Flink? Do I need to use a timerservice for this where the > callback will be a window.maxtimestamp() or just clearing the cache in the > clear method will do the trick? > > -- > > *Regards,Harshvardhan Agrawal* >
