Kafka Stream: How to trigger event based on hopping windows and how to trigger event based on combined set of windows that are part of hopping window

问题

Here is our topology:

test-events--->groupByKey-->Window Aggregation-->Suppress-->Filter-->rekey

Here is the flow

We have 1 min hopping window. With total window size of 5 min. The hopping window is evaluated every five minutes, HOW to get count of every 1 min hops??

Total 5 min window, hop duration 1 min.

1. How to TRIGGER some event based on 1 min HOP

2. How to TRIGGER some event based on TOTAL 5 min WINDOW


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We want to do 2 things.

1. We want to count total number of events in a hopping window of 1 min. If total number of events are > some threshold then trigger one combined event for that 1 min hopping window.

2. Then we want to trigger an alert if count of combined event is > some number.

From Kafka window API

Code looks like this:
KStream<String, DataPointUri> KS0 = builder.stream(inputTopicsList,);
KGroupedStream<String, DataPointUri> KS1 = KS0.groupByKey();
Duration windowDuration =getDuration(...)); 
Duration hopDuration =getDuration(env.getProperty(...)));
TimeWindowedKStream<String, DataPointUri> KS2 = KS1.windowedBy(TimeWindows.of(windowDuration).advanceBy(hopDuration).grace(Duration.ofSeconds(10)));
KTable<Windowed<String>, Long> uriCount = KS2.count(Materialized.<String, Long, WindowStore<Bytes, byte[]>>with(Serdes.String(), Serdes.Long()));

Here we are getting count for 5 min window. NOT for hop 1 min window. How to get details of 1 min window?

来源：https://stackoverflow.com/questions/65171532/kafka-stream-how-to-trigger-event-based-on-hopping-windows-and-how-to-trigger-e