Configure minimum lag at 1 (and not 0) ?

[enavarro222]

I try to use Burrow to monitor a bunch of services build with robinhood faust python library.

The point is that faust has a different understanding of kafka consumer's offset. For faust offset is the last event offset, not the "next expected event" offset. see https://github.com/robinhood/faust/issues/73

So a faust based services always have a minimal lag of 1 (and not 0). And so burrow set an error status when there is no commit for some times...

In my point of view the issue comes from faust interpretation of these offset. so => https://github.com/robinhood/faust/issues/73

But, anyway, I post this for two reasons :

• for documentation (I couldn't found any reference of this issue on burrow github)
• I wounder if there is a -not-so-dirty- way to configure burrow to handle this minimal lag at 1 ?

btw, thanks for you work on burrow !

[stefan-as]

Seems to be also an issue when using Exactly-Once Semantics (https://cwiki.apache.org/confluence/display/KAFKA/KIP-129%3A+Streams+Exactly-Once+Semantics). As far as I understand the situation, with Kafka EOS enabled, there are additional transaction messages leading to a permanent lag of 1.

[davispw]

This is blocking my reliable use of burrow in pre-prod environments where there is not a constant data flow on some topics. It is causing false alerts. Suggestions?