Saving state from UDFs with group by in Kapacitor

InfluxDB 1 Kapacitor
1

I have looked at the moving average and outlier examples and want to make sure I am understanding the code correctly.

My concern is “How do you save state for UDFs when there is a group by in the initial stream”

If i’m reading this correctly, This is saying there is a state per group getting saved and its adding new “states” for an unseen group.

if point.group not in self._state:
self._state[point.group] = AvgHandler.state(self._size)
avg = self._state[point.group].update(value)

Then in snapshot / restore we iterate through each one.
Am Interpretting this correctly?

2

Yes, that is correct, The UDF will be passed all data for all groups. It is the responsibility of the UDF to track the state per group.

1 Like
3

So then how can you override the group to set a different index?