Hello,
Let's say, my elements are simple key-value pairs, elements are coming from
Kafka, where they were partitioned by "key", then I do processing using
KeyedProcessFunction (keyed by same "key"), then I enrich elements using
ordered RichAsyncFunction, then output to another KeyedProcessFunction (keyed
by same "key") and then write to Kafka topic, again partitioned by same "key",
something like this:
FlinkKafkaConsumer -> keyBy("key") -> Intake(KeyedProcessFunction) ->
AsyncDataStream.orderedWait() ->
keyBy("key")->Output(KeyedProcessFunction)->FlinkKafkaProducer
Will it preserve order of events with same "key"?
* Will Output function receive elements with same "key" in same order as
they were originally in Kafka?
* Will FlinkKafkaProducer writes elements with same "key" in same order as
they were originally in Kafka?
* Does it depend on parallelism of async IO? Documentation says "the stream
order is preserved", but if there are multiple parallel instances of async
function, does it mean order relative to each single instance? Or total stream
order?
Thanks,
Alexey
