Kafka ControllerRegistration Response Wire Format v0 — Binary Protocol Layout

What is ControllerRegistration?

Dedicated KRaft controller nodes (non-broker controllers) send this to register with the active controller on startup. This is the controller equivalent of BrokerRegistration, specific to deployments where controller nodes don't host topic partitions.

Schema
{
  "ThrottleTimeMs": int32,
  "ErrorCode": int16,
  "ErrorMessage": string?
}

Example
{
  "ThrottleTimeMs": 0,
  "ErrorCode": 0,
  "ErrorMessage": "NETWORK_EXCEPTION"
}