Hi Yassine, Could you just remove the window and the apply, and just put a print() after the: > .assignTimestampsAndWatermarks(new AscendingTimestampExtractor<Request>() { > @Override > public long extractAscendingTimestamp(Request req) { > return req.ts; > } > })
This at least will tell us if reading from Kafka works as expected. Kostas > On Jul 25, 2016, at 3:39 PM, Yassin Marzouki <yassmar...@gmail.com> wrote: > > Hi everyone, > > I am reading messages from a Kafka topic with 2 partitions and using event > time. This is my code: > > .assignTimestampsAndWatermarks(new AscendingTimestampExtractor<Request>() { > @Override > public long extractAscendingTimestamp(Request req) { > return req.ts; > } > }) > .windowAll(TumblingEventTimeWindows.of(Time.days(1))) > .apply((TimeWindow window, Iterable<Request> iterable, Collector<String> > collector) -> { > collector.collect("Window: " + window.toString()); > for (Request req : iterable) { > collector.collect(req.toString()); > } > }) > .print() > > I could get an output only when setting the kafka source parallelism to 1. I > guess that is because messages from multiple partitions arrive out-of-order > to the timestamp exctractor according to this thread > <http://apache-flink-user-mailing-list-archive.2336050.n4.nabble.com/Kafka-partition-alignment-for-event-time-td4782.html#a4804>, > correct? > So I replaced the AscendingTimestampExtractor with a > BoundedOutOfOrdernessGenerator as in the documentation example > <https://ci.apache.org/projects/flink/flink-docs-master/apis/streaming/event_timestamps_watermarks.html#tab_java_3> > (with a higher delay) in order to handle out-of-order events, but I still > can't get any output. Why is that? > > Best, > Yassine >