There are also versions of WindowedStream#aggregate that accept an
additional WindowFunction/ProcessWindowFunction, which do have access to
the key via apply()/process() respectively. These functions are called
post aggregation.
On 08.02.2019 18:24, stephen.alan.conno...@gmail.com wrote:
If I write my aggregation logic as a WindowFunction then I get access to the
key as the first parameter in WindowFunction.apply(...) however the Javadocs
for calling WindowedStream.apply(WindowFunction) state:
Note that this function requires that all data in the windows is buffered until
the window
is evaluated, as the function provides no means of incremental aggregation.
Which sounds bad.
It seems the recommended alternative is to use one of the
WindowFunction.aggregate(AggregateFunction) however I cannot see how to get
access to the key...
Is my only solution to transform my data into a Tuple if I need access to the
key post aggregation?
Thanks in advance
-stephenc
