What is FindCoordinator?
The first step before any group or transaction operation: locates the group coordinator or transaction coordinator. A COORDINATOR_NOT_AVAILABLE response means the __consumer_offsets or __transaction_state partition leader is still being elected; retry with backoff.
Wire Diagram
Response Header · flexible
message_size
int32 · 4B
correlation_id
int32 · 4B
tagged
var
FindCoordinatorResponse v3
ThrottleTimeMs
int32 · 4B
ErrorCode
int16 · 2B
ErrorMessage?
string (compact)
NodeId
int32 · 4B
Host
string (compact)
Port
int32 · 4B
tagged
var
Schema & Example
Schema { "ThrottleTimeMs": int32, "ErrorCode": int16, "ErrorMessage": string?, "NodeId": int32, "Host": string, "Port": int32 }
Example { "ThrottleTimeMs": 0, "ErrorCode": 0, "ErrorMessage": "NETWORK_EXCEPTION", "NodeId": 1, "Host": "broker-1.kafka.local", "Port": 9092 }