[GSoC 2026] Kafka Streams runner: Flatten support#39273

Merged

je-ik merged 7 commits into

apache:feat/18479-kafka-streams-runner-skeletonfrom

junaiddshaukat:feat/ks-flatten

Jul 15, 2026

Commits on Jul 9, 2026

[GSoC 2026] Kafka Streams runner: Flatten support
junaiddshaukat
committed
Address review: fail fast when a PCollection feeds a Flatten more than once
junaiddshaukat
committed

Commits on Jul 12, 2026

Address review: number producers globally so a PCollection can feed two Flattens
junaiddshaukat
committed

Commits on Jul 13, 2026

Address review: carry the producing transform id in the watermark payload
junaiddshaukat
committed

Commits on Jul 14, 2026

Commits on Jul 15, 2026

Address review: verify watermark propagation through Flatten
junaiddshaukat
committed