TimeExpiry and LengthExpiry windows to Siddhi

[suhothayan]

Description:
At times we need windows updates immediately but we need to rest the window aggregations time to time. Such that the window count() will gradually increase and resets to zero on a periodic time or length interval.
Unfortunately, the current Siddhi windows ( (Sliding)Time, (Sliding) Length, Time Batch and Length Batch windows) do not support this requirement.

Therefore I'm proposing TimeExpiry and LengthExpiry windows to Siddhi to support this feature.

Affected Siddhi Version:
4.4.8

[mohanvive]

Shall we improve the existing window implementations by adding a new flag as "isStreamingCurrentEvents" to achieve above?

[suhothayan]

I'll improve the timeBatch and lengthBatch windows with a bool parameter "stream.current.event".

[suhothayan]

The feature for this is added via #1057. Hence closing this issue