On Sun, 10 Feb 2019 at 09:48, Chesnay Schepler <ches...@apache.org> wrote:
> 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. > Cool I'll chase those down > > 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 > > > >
