Hey Chia-Ping, Thanks for the feedback.
chia_0: the headers must be serialized as a byte array. I updated the KIP about that. chia_1: this is the reason different store types are introduced. The newly introduced stores keep the headers, while the current ones not. chia_2: that’s a valid point. I think it’s better to keep the order rather than change it. Bests, Alieh On Sat, Jan 10, 2026 at 2:21 AM Chia-Ping Tsai <[email protected]> wrote: > hi Alieh > > Thanks for the KIP. This proposal seems to open the door for many > interesting use cases. I have a few questions? > > chia_0: could you clarify the serialization format of headers_bytes? > > chia_1: how does the state store distinguish between legacy values and > new values with headers? Since the new format starts with a 2-bytes length, > is there a risk of ambiguity with existing data? > > chia_2: does the implementation guarantee that the order of headers is > preserved > > Best, > Chia-Ping > > > > > Alieh Saeedi via dev <[email protected]> 於 2026年1月10日 清晨6:14 寫道： > > > > Hi all, > > > > I’d like to start a discussion on KIP-1271, which proposes allowing Kafka > > Streams state stores to preserve record headers. > > This would let header-based metadata like schema IDs, tracing info, and > > feature flags be stored and restored alongside values. > > The KIP introduces header-aware store types and a small config to cap the > > size of headers written into state. > > Details are in the KIP: > > > https://cwiki.apache.org/confluence/display/KAFKA/KIP-1271%3A+Allow+to+Store+Record+Headers+in+State+Stores > > . > > I’d appreciate your feedback and questions on the proposal. > > > > Thanks, > > Alieh >
