Hi,
looking into the code of PeriodicSequence (which is used by
PeriodicImpulse) it seems it uses SDF, but does not update downstream
watermark using WatermarkEstimator in the @ProcessElement method. That
seems to produce outputs only after the Pipeline terminates (at least it
seems to work this way on Flink runner). Is this bug in the
PeriodicImpulse (would be fixed by adding ManualWatermarkEstimator,
possibly), or in the Flink's SDF implementation? I suspect it is the
first one, because I cannot imagine how would the runner infer the
watermark without being explicitly told by the SDF.
Should this be fixed in the PeriodicSequence?
Jan
