Anton Agestam created KAFKA-15869:
-------------------------------------
Summary: Document semantics of nullable nested API entities
Key: KAFKA-15869
URL: https://issues.apache.org/jira/browse/KAFKA-15869
Project: Kafka
Issue Type: Wish
Reporter: Anton Agestam
The initial version of ConsumerGroupHeartbeatResponse [introduced the first
field across the protocol that is a nullable nested
entity|https://github.com/dajac/kafka/blob/3acd87a3e82e1d2fd4c07218d362e7665b99c547/clients/src/main/resources/common/message/ConsumerGroupHeartbeatResponse.json#L48].
As the implementor of a third-party schema parser it is not clear how to
handle this field, where such fields are allowed, and how null is represented
for such fields.
As far as I can tell, the [protocol
guide|https://kafka.apache.org/protocol.html#The_Messages_ConsumerGroupHeartbeat]
does not mention the nullability at all.
The reason I ask where such fields are allowed is because if the answer to how
null is represented here is just omitting writing any bytes, then I suspect the
only unambiguous place for such field to appear would be as the last field of a
top-level entity. Even then, how is it discriminated from tagged fields?
Is it possible this field was made nullable by mistake?
--
This message was sent by Atlassian Jira
(v8.20.10#820010)
