Hi all,
Hope you are doing well. I'm starting this thread to discuss $title. As
we discussed in the mail thread [1], having a common window semantic that
can be leveraged by every PE can be very useful.
I'm thinking of two ways to achieve the same;
1. Introduce a dedicated Window PE which can be used before any existing
PE.
- No need for API changes.
- But, might have to flag event in a way for the next processor to
identify, to which window the event belongs to (i.e with sliding windows,
etc...).
- So, have to change the processing logic of existing PEs to check
event flag and process accordingly.
- So all the existing PEs might not work with window semantics. In
that case, we need a way to show window compatible PEs (because, having a
window before a normal PE might result in un-expected outputs)
2. Introduce windowed EventProcessor/EventSink APIs which allows users
to write their own windowed extensions (i.e aggregators, etc...)
- No need for event flagging. Can introduce API methods like
onCurrentEvent, onExpiredEvent, onResetEvent, etc...
- Need API changes/refactoring in EventProcessor/EventSink, as well
as in existing PEs.
- Need a way to expose the window related parameters through existing
PEs DataProcessorDescription.
Since there're pros/cons to both, what do you think is the best approach?
Or is there any other approach that we can try out?
[1] PE to rate-limit events
Grainier Perera.
