Hello Tom, There is no specific release date planned yet, but we are shooting for adding kafka-streams in the next major release of Kafka.
Regarding exactly-once semantics, the first version of kafka-streams may not yet have this feature implemented but we do have designs and target to add it in a later release this year. Guozhang On Thu, Jan 14, 2016 at 3:17 AM, Tom Dearman <tom.dear...@gmail.com> wrote: > Can anyone tell me whether the kaka-streams project will resolve the issue > noted in the KIP-28: > > “After processor writes to a store instance, it first sends the change > message to its corresponding changelog topic partition. When user calls > commit() in his processor, KStream needs to flush both the store instance > as well as the producer sending to the changelog, as well as committing the > offset in the upstream Kafka. If these three operations cannot be done > atomically, then if there is a crash in between this operations duplicates > could be generated since the upstream Kafka committing offset is executed > in the last step; if there three operations can be done atomically, then we > can guarantee "exactly-once" semantics.” > > Does this requirement essentially mean that kafka-streams will not work > until transactional support is implemented in kafka. Is kafka-streams going > to be in the 0.10 release. Is transactional support still going into > release 0.10 and does this look likely to be for Q2 2016 which is the > present schedule. > > Thanks. > > > -- -- Guozhang
