Api Keys

The following are the numeric codes that the ApiKey in the request can take for each of the above request types.

Name	Key
Produce	0
Fetch	1
Offsets	2
Metadata	3
LeaderAndIsr	4
StopReplica	5
UpdateMetadata	6
ControlledShutdown	7
OffsetCommit	8
OffsetFetch	9
GroupCoordinator	10
JoinGroup	11
Heartbeat	12
LeaveGroup	13
SyncGroup	14
DescribeGroups	15
ListGroups	16

Error Codes

We use numeric codes to indicate what problem occurred on the server. These can be translated by the client into exceptions or whatever the appropriate error handling mechanism in the client language. Here is a table of the error codes currently in use:

Error	Code	Retriable	Description
UNKNOWN	-1	False	The server experienced an unexpected error when processing the request
NONE	0	False
OFFSET_OUT_OF_RANGE	1	False	The requested offset is not within the range of offsets maintained by the server.
CORRUPT_MESSAGE	2	True	This message has failed its CRC checksum, exceeds the valid size, or is otherwise corrupt.
UNKNOWN_TOPIC_OR_PARTITION	3	True	This server does not host this topic-partition.
INVALID_FETCH_SIZE	4	False	The requested fetch size is invalid.
LEADER_NOT_AVAILABLE	5	True	There is no leader for this topic-partition as we are in the middle of a leadership election.
NOT_LEADER_FOR_PARTITION	6	True	This server is not the leader for that topic-partition.
REQUEST_TIMED_OUT	7	True	The request timed out.
BROKER_NOT_AVAILABLE	8	False	The broker is not available.
REPLICA_NOT_AVAILABLE	9	False	The replica is not available for the requested topic-partition
MESSAGE_TOO_LARGE	10	False	The request included a message larger than the max message size the server will accept.
STALE_CONTROLLER_EPOCH	11	False	The controller moved to another broker.
OFFSET_METADATA_TOO_LARGE	12	False	The metadata field of the offset request was too large.
NETWORK_EXCEPTION	13	True	The server disconnected before a response was received.
GROUP_LOAD_IN_PROGRESS	14	True	The coordinator is loading and hence can't process requests for this group.
GROUP_COORDINATOR_NOT_AVAILABLE	15	True	The group coordinator is not available.
NOT_COORDINATOR_FOR_GROUP	16	True	This is not the correct coordinator for this group.
INVALID_TOPIC_EXCEPTION	17	False	The request attempted to perform an operation on an invalid topic.
RECORD_LIST_TOO_LARGE	18	False	The request included message batch larger than the configured segment size on the server.
NOT_ENOUGH_REPLICAS	19	True	Messages are rejected since there are fewer in-sync replicas than required.
NOT_ENOUGH_REPLICAS_AFTER_APPEND	20	True	Messages are written to the log, but to fewer in-sync replicas than required.
INVALID_REQUIRED_ACKS	21	False	Produce request specified an invalid value for required acks.
ILLEGAL_GENERATION	22	False	Specified group generation id is not valid.
INCONSISTENT_GROUP_PROTOCOL	23	False	The group member's supported protocols are incompatible with those of existing members.
INVALID_GROUP_ID	24	False	The configured groupId is invalid
UNKNOWN_MEMBER_ID	25	False	The coordinator is not aware of this member.
INVALID_SESSION_TIMEOUT	26	False	The session timeout is not within an acceptable range.
REBALANCE_IN_PROGRESS	27	False	The group is rebalancing, so a rejoin is needed.
INVALID_COMMIT_OFFSET_SIZE	28	False	The committing offset data size is not valid
TOPIC_AUTHORIZATION_FAILED	29	False	Not authorized to access topics: [Topic authorization failed.]
GROUP_AUTHORIZATION_FAILED	30	False	Not authorized to access group: Group authorization failed.
CLUSTER_AUTHORIZATION_FAILED	31	False	Cluster authorization failed.
INVALID_TIMESTAMP	32	False	The timestamp of the message is out of acceptable range.

Headers:

Request Header => api_key api_version correlation_id client_id 
  api_key => INT16
  api_version => INT16
  correlation_id => INT32
  client_id => NULLABLE_STRING

Response Header => correlation_id 
  correlation_id => INT32

Produce API (Key: 0):

Requests:

Produce Request (Version: 0) => acks timeout [topic_data] 
  topic_data => topic [data] 
    data => partition record_set 
      partition => INT32
      record_set => BYTES
    topic => STRING
  acks => INT16
  timeout => INT32

Field	Description
acks	The number of nodes that should replicate the produce before returning. -1 indicates the full ISR.
timeout	The time to await a response in ms.
topic_data
topic
data
partition
record_set

Produce Request (Version: 1) => acks timeout [topic_data] 
  topic_data => topic [data] 
    data => partition record_set 
      partition => INT32
      record_set => BYTES
    topic => STRING
  acks => INT16
  timeout => INT32

Field	Description
acks	The number of nodes that should replicate the produce before returning. -1 indicates the full ISR.
timeout	The time to await a response in ms.
topic_data
topic
data
partition
record_set

Produce Request (Version: 2) => acks timeout [topic_data] 
  topic_data => topic [data] 
    data => partition record_set 
      partition => INT32
      record_set => BYTES
    topic => STRING
  acks => INT16
  timeout => INT32

Field	Description
acks	The number of nodes that should replicate the produce before returning. -1 indicates the full ISR.
timeout	The time to await a response in ms.
topic_data
topic
data
partition
record_set

Responses:

Produce Response (Version: 0) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code base_offset 
      partition => INT32
      error_code => INT16
      base_offset => INT64
    topic => STRING

Field	Description
acks	The number of nodes that should replicate the produce before returning. -1 indicates the full ISR.
timeout	The time to await a response in ms.
topic_data
topic
data
partition
record_set

Produce Response (Version: 1) => [responses] throttle_time_ms 
  responses => topic [partition_responses] 
    partition_responses => partition error_code base_offset 
      partition => INT32
      error_code => INT16
      base_offset => INT64
    topic => STRING
  throttle_time_ms => INT32

Field	Description
acks	The number of nodes that should replicate the produce before returning. -1 indicates the full ISR.
timeout	The time to await a response in ms.
topic_data
topic
data
partition
record_set

Produce Response (Version: 2) => [responses] throttle_time_ms 
  responses => topic [partition_responses] 
    partition_responses => partition error_code base_offset timestamp 
      partition => INT32
      error_code => INT16
      base_offset => INT64
      timestamp => INT64
    topic => STRING
  throttle_time_ms => INT32

Field	Description
acks	The number of nodes that should replicate the produce before returning. -1 indicates the full ISR.
timeout	The time to await a response in ms.
topic_data
topic
data
partition
record_set

Fetch API (Key: 1):

Requests:

Fetch Request (Version: 0) => replica_id max_wait_time min_bytes [topics] 
  topics => topic [partitions] 
    partitions => partition fetch_offset max_bytes 
      partition => INT32
      fetch_offset => INT64
      max_bytes => INT32
    topic => STRING
  replica_id => INT32
  max_wait_time => INT32
  min_bytes => INT32

Field	Description
replica_id	Broker id of the follower. For normal consumers, use -1.
max_wait_time	Maximum time in ms to wait for the response.
min_bytes	Minimum bytes to accumulate in the response.
topics	Topics to fetch.
topic	Topic to fetch.
partitions	Partitions to fetch.
partition	Topic partition id.
fetch_offset	Message offset.
max_bytes	Maximum bytes to fetch.

Fetch Request (Version: 1) => replica_id max_wait_time min_bytes [topics] 
  topics => topic [partitions] 
    partitions => partition fetch_offset max_bytes 
      partition => INT32
      fetch_offset => INT64
      max_bytes => INT32
    topic => STRING
  replica_id => INT32
  max_wait_time => INT32
  min_bytes => INT32

Field	Description
replica_id	Broker id of the follower. For normal consumers, use -1.
max_wait_time	Maximum time in ms to wait for the response.
min_bytes	Minimum bytes to accumulate in the response.
topics	Topics to fetch.
topic	Topic to fetch.
partitions	Partitions to fetch.
partition	Topic partition id.
fetch_offset	Message offset.
max_bytes	Maximum bytes to fetch.

Fetch Request (Version: 2) => replica_id max_wait_time min_bytes [topics] 
  topics => topic [partitions] 
    partitions => partition fetch_offset max_bytes 
      partition => INT32
      fetch_offset => INT64
      max_bytes => INT32
    topic => STRING
  replica_id => INT32
  max_wait_time => INT32
  min_bytes => INT32

Field	Description
replica_id	Broker id of the follower. For normal consumers, use -1.
max_wait_time	Maximum time in ms to wait for the response.
min_bytes	Minimum bytes to accumulate in the response.
topics	Topics to fetch.
topic	Topic to fetch.
partitions	Partitions to fetch.
partition	Topic partition id.
fetch_offset	Message offset.
max_bytes	Maximum bytes to fetch.

Responses:

Fetch Response (Version: 0) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code high_watermark record_set 
      partition => INT32
      error_code => INT16
      high_watermark => INT64
      record_set => BYTES
    topic => STRING

Field	Description
replica_id	Broker id of the follower. For normal consumers, use -1.
max_wait_time	Maximum time in ms to wait for the response.
min_bytes	Minimum bytes to accumulate in the response.
topics	Topics to fetch.
topic	Topic to fetch.
partitions	Partitions to fetch.
partition	Topic partition id.
fetch_offset	Message offset.
max_bytes	Maximum bytes to fetch.

Fetch Response (Version: 1) => throttle_time_ms [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code high_watermark record_set 
      partition => INT32
      error_code => INT16
      high_watermark => INT64
      record_set => BYTES
    topic => STRING
  throttle_time_ms => INT32

Field	Description
replica_id	Broker id of the follower. For normal consumers, use -1.
max_wait_time	Maximum time in ms to wait for the response.
min_bytes	Minimum bytes to accumulate in the response.
topics	Topics to fetch.
topic	Topic to fetch.
partitions	Partitions to fetch.
partition	Topic partition id.
fetch_offset	Message offset.
max_bytes	Maximum bytes to fetch.

Fetch Response (Version: 2) => throttle_time_ms [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code high_watermark record_set 
      partition => INT32
      error_code => INT16
      high_watermark => INT64
      record_set => BYTES
    topic => STRING
  throttle_time_ms => INT32

Field	Description
replica_id	Broker id of the follower. For normal consumers, use -1.
max_wait_time	Maximum time in ms to wait for the response.
min_bytes	Minimum bytes to accumulate in the response.
topics	Topics to fetch.
topic	Topic to fetch.
partitions	Partitions to fetch.
partition	Topic partition id.
fetch_offset	Message offset.
max_bytes	Maximum bytes to fetch.

Offsets API (Key: 2):

Requests:

Offsets Request (Version: 0) => replica_id [topics] 
  topics => topic [partitions] 
    partitions => partition timestamp max_num_offsets 
      partition => INT32
      timestamp => INT64
      max_num_offsets => INT32
    topic => STRING
  replica_id => INT32

Field	Description
replica_id	Broker id of the follower. For normal consumers, use -1.
topics	Topics to list offsets.
topic	Topic to list offset.
partitions	Partitions to list offset.
partition	Topic partition id.
timestamp	Timestamp.
max_num_offsets	Maximum offsets to return.

Responses:

Offsets Response (Version: 0) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code [offsets] 
      partition => INT32
      error_code => INT16
    topic => STRING

Field	Description
replica_id	Broker id of the follower. For normal consumers, use -1.
topics	Topics to list offsets.
topic	Topic to list offset.
partitions	Partitions to list offset.
partition	Topic partition id.
timestamp	Timestamp.
max_num_offsets	Maximum offsets to return.

Metadata API (Key: 3):

Requests:

Metadata Request (Version: 0) => [topics]

Field	Description
topics	An array of topics to fetch metadata for. If no topics are specified fetch metadata for all topics.

Responses:

Metadata Response (Version: 0) => [brokers] [topic_metadata] 
  brokers => node_id host port 
    node_id => INT32
    host => STRING
    port => INT32
  topic_metadata => topic_error_code topic [partition_metadata] 
    partition_metadata => partition_error_code partition_id leader [replicas] [isr] 
      partition_error_code => INT16
      partition_id => INT32
      leader => INT32
    topic_error_code => INT16
    topic => STRING

Field	Description
topics	An array of topics to fetch metadata for. If no topics are specified fetch metadata for all topics.

LeaderAndIsr API (Key: 4):

Requests:

LeaderAndIsr Request (Version: 0) => controller_id controller_epoch [partition_states] [live_leaders] 
  partition_states => topic partition controller_epoch leader leader_epoch [isr] zk_version [replicas] 
    topic => STRING
    partition => INT32
    controller_epoch => INT32
    leader => INT32
    leader_epoch => INT32
    zk_version => INT32
  live_leaders => id host port 
    id => INT32
    host => STRING
    port => INT32
  controller_id => INT32
  controller_epoch => INT32

Field	Description
controller_id	The controller id.
controller_epoch	The controller epoch.
partition_states
topic	Topic name.
partition	Topic partition id.
controller_epoch	The controller epoch.
leader	The broker id for the leader.
leader_epoch	The leader epoch.
isr	The in sync replica ids.
zk_version	The ZK version.
replicas	The replica ids.
live_leaders
id	The broker id.
host	The hostname of the broker.
port	The port on which the broker accepts requests.

Responses:

LeaderAndIsr Response (Version: 0) => error_code [partitions] 
  partitions => topic partition error_code 
    topic => STRING
    partition => INT32
    error_code => INT16
  error_code => INT16

Field	Description
controller_id	The controller id.
controller_epoch	The controller epoch.
partition_states
topic	Topic name.
partition	Topic partition id.
controller_epoch	The controller epoch.
leader	The broker id for the leader.
leader_epoch	The leader epoch.
isr	The in sync replica ids.
zk_version	The ZK version.
replicas	The replica ids.
live_leaders
id	The broker id.
host	The hostname of the broker.
port	The port on which the broker accepts requests.

StopReplica API (Key: 5):

Requests:

StopReplica Request (Version: 0) => controller_id controller_epoch delete_partitions [partitions] 
  partitions => topic partition 
    topic => STRING
    partition => INT32
  controller_id => INT32
  controller_epoch => INT32
  delete_partitions => INT8

Field	Description
controller_id	The controller id.
controller_epoch	The controller epoch.
delete_partitions	Boolean which indicates if replica's partitions must be deleted.
partitions
topic	Topic name.
partition	Topic partition id.

Responses:

StopReplica Response (Version: 0) => error_code [partitions] 
  partitions => topic partition error_code 
    topic => STRING
    partition => INT32
    error_code => INT16
  error_code => INT16

Field	Description
controller_id	The controller id.
controller_epoch	The controller epoch.
delete_partitions	Boolean which indicates if replica's partitions must be deleted.
partitions
topic	Topic name.
partition	Topic partition id.

UpdateMetadata API (Key: 6):

Requests:

UpdateMetadata Request (Version: 0) => controller_id controller_epoch [partition_states] [live_brokers] 
  partition_states => topic partition controller_epoch leader leader_epoch [isr] zk_version [replicas] 
    topic => STRING
    partition => INT32
    controller_epoch => INT32
    leader => INT32
    leader_epoch => INT32
    zk_version => INT32
  live_brokers => id host port 
    id => INT32
    host => STRING
    port => INT32
  controller_id => INT32
  controller_epoch => INT32

Field	Description
controller_id	The controller id.
controller_epoch	The controller epoch.
partition_states
topic	Topic name.
partition	Topic partition id.
controller_epoch	The controller epoch.
leader	The broker id for the leader.
leader_epoch	The leader epoch.
isr	The in sync replica ids.
zk_version	The ZK version.
replicas	The replica ids.
live_brokers
id	The broker id.
host	The hostname of the broker.
port	The port on which the broker accepts requests.

UpdateMetadata Request (Version: 1) => controller_id controller_epoch [partition_states] [live_brokers] 
  partition_states => topic partition controller_epoch leader leader_epoch [isr] zk_version [replicas] 
    topic => STRING
    partition => INT32
    controller_epoch => INT32
    leader => INT32
    leader_epoch => INT32
    zk_version => INT32
  live_brokers => id [end_points] 
    end_points => port host security_protocol_type 
      port => INT32
      host => STRING
      security_protocol_type => INT16
    id => INT32
  controller_id => INT32
  controller_epoch => INT32

Field	Description
controller_id	The controller id.
controller_epoch	The controller epoch.
partition_states
topic	Topic name.
partition	Topic partition id.
controller_epoch	The controller epoch.
leader	The broker id for the leader.
leader_epoch	The leader epoch.
isr	The in sync replica ids.
zk_version	The ZK version.
replicas	The replica ids.
live_brokers
id	The broker id.
end_points
port	The port on which the broker accepts requests.
host	The hostname of the broker.
security_protocol_type	The security protocol type.

Responses:

UpdateMetadata Response (Version: 0) => error_code 
  error_code => INT16

Field	Description
controller_id	The controller id.
controller_epoch	The controller epoch.
partition_states
topic	Topic name.
partition	Topic partition id.
controller_epoch	The controller epoch.
leader	The broker id for the leader.
leader_epoch	The leader epoch.
isr	The in sync replica ids.
zk_version	The ZK version.
replicas	The replica ids.
live_brokers
id	The broker id.
host	The hostname of the broker.
port	The port on which the broker accepts requests.

UpdateMetadata Response (Version: 1) => error_code 
  error_code => INT16

Field	Description
controller_id	The controller id.
controller_epoch	The controller epoch.
partition_states
topic	Topic name.
partition	Topic partition id.
controller_epoch	The controller epoch.
leader	The broker id for the leader.
leader_epoch	The leader epoch.
isr	The in sync replica ids.
zk_version	The ZK version.
replicas	The replica ids.
live_brokers
id	The broker id.
end_points
port	The port on which the broker accepts requests.
host	The hostname of the broker.
security_protocol_type	The security protocol type.

ControlledShutdown API (Key: 7):

Requests:

ControlledShutdown Request (Version: 1) => broker_id 
  broker_id => INT32

Field	Description
broker_id	The id of the broker for which controlled shutdown has been requested.

Responses:

ControlledShutdown Response (Version: 1) => error_code [partitions_remaining] 
  partitions_remaining => topic partition 
    topic => STRING
    partition => INT32
  error_code => INT16

Field	Description
broker_id	The id of the broker for which controlled shutdown has been requested.

OffsetCommit API (Key: 8):

Requests:

OffsetCommit Request (Version: 0) => group_id [topics] 
  topics => topic [partitions] 
    partitions => partition offset metadata 
      partition => INT32
      offset => INT64
      metadata => STRING
    topic => STRING
  group_id => STRING

Field	Description
group_id	The group id.
topics	Topics to commit offsets.
topic	Topic to commit.
partitions	Partitions to commit offsets.
partition	Topic partition id.
offset	Message offset to be committed.
metadata	Any associated metadata the client wants to keep.

OffsetCommit Request (Version: 1) => group_id group_generation_id member_id [topics] 
  topics => topic [partitions] 
    partitions => partition offset timestamp metadata 
      partition => INT32
      offset => INT64
      timestamp => INT64
      metadata => STRING
    topic => STRING
  group_id => STRING
  group_generation_id => INT32
  member_id => STRING

Field	Description
group_id	The group id.
group_generation_id	The generation of the group.
member_id	The member id assigned by the group coordinator.
topics	Topics to commit offsets.
topic	Topic to commit.
partitions	Partitions to commit offsets.
partition	Topic partition id.
offset	Message offset to be committed.
timestamp	Timestamp of the commit
metadata	Any associated metadata the client wants to keep.

OffsetCommit Request (Version: 2) => group_id group_generation_id member_id retention_time [topics] 
  topics => topic [partitions] 
    partitions => partition offset metadata 
      partition => INT32
      offset => INT64
      metadata => STRING
    topic => STRING
  group_id => STRING
  group_generation_id => INT32
  member_id => STRING
  retention_time => INT64

Field	Description
group_id	The group id.
group_generation_id	The generation of the consumer group.
member_id	The consumer id assigned by the group coordinator.
retention_time	Time period in ms to retain the offset.
topics	Topics to commit offsets.
topic	Topic to commit.
partitions	Partitions to commit offsets.
partition	Topic partition id.
offset	Message offset to be committed.
metadata	Any associated metadata the client wants to keep.

Responses:

OffsetCommit Response (Version: 0) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code 
      partition => INT32
      error_code => INT16
    topic => STRING

Field	Description
group_id	The group id.
topics	Topics to commit offsets.
topic	Topic to commit.
partitions	Partitions to commit offsets.
partition	Topic partition id.
offset	Message offset to be committed.
metadata	Any associated metadata the client wants to keep.

OffsetCommit Response (Version: 1) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code 
      partition => INT32
      error_code => INT16
    topic => STRING

Field	Description
group_id	The group id.
group_generation_id	The generation of the group.
member_id	The member id assigned by the group coordinator.
topics	Topics to commit offsets.
topic	Topic to commit.
partitions	Partitions to commit offsets.
partition	Topic partition id.
offset	Message offset to be committed.
timestamp	Timestamp of the commit
metadata	Any associated metadata the client wants to keep.

OffsetCommit Response (Version: 2) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code 
      partition => INT32
      error_code => INT16
    topic => STRING

Field	Description
group_id	The group id.
group_generation_id	The generation of the consumer group.
member_id	The consumer id assigned by the group coordinator.
retention_time	Time period in ms to retain the offset.
topics	Topics to commit offsets.
topic	Topic to commit.
partitions	Partitions to commit offsets.
partition	Topic partition id.
offset	Message offset to be committed.
metadata	Any associated metadata the client wants to keep.

OffsetFetch API (Key: 9):

Requests:

OffsetFetch Request (Version: 0) => group_id [topics] 
  topics => topic [partitions] 
    partitions => partition 
      partition => INT32
    topic => STRING
  group_id => STRING

Field	Description
group_id	The consumer group id.
topics	Topics to fetch offsets.
topic	Topic to fetch offset.
partitions	Partitions to fetch offsets.
partition	Topic partition id.

OffsetFetch Request (Version: 1) => group_id [topics] 
  topics => topic [partitions] 
    partitions => partition 
      partition => INT32
    topic => STRING
  group_id => STRING

Field	Description
group_id	The consumer group id.
topics	Topics to fetch offsets.
topic	Topic to fetch offset.
partitions	Partitions to fetch offsets.
partition	Topic partition id.

Responses:

OffsetFetch Response (Version: 0) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition offset metadata error_code 
      partition => INT32
      offset => INT64
      metadata => STRING
      error_code => INT16
    topic => STRING

Field	Description
group_id	The consumer group id.
topics	Topics to fetch offsets.
topic	Topic to fetch offset.
partitions	Partitions to fetch offsets.
partition	Topic partition id.

OffsetFetch Response (Version: 1) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition offset metadata error_code 
      partition => INT32
      offset => INT64
      metadata => STRING
      error_code => INT16
    topic => STRING

Field	Description
group_id	The consumer group id.
topics	Topics to fetch offsets.
topic	Topic to fetch offset.
partitions	Partitions to fetch offsets.
partition	Topic partition id.

GroupCoordinator API (Key: 10):

Requests:

GroupCoordinator Request (Version: 0) => group_id 
  group_id => STRING

Field	Description
group_id	The unique group id.

Responses:

GroupCoordinator Response (Version: 0) => error_code coordinator 
  coordinator => node_id host port 
    node_id => INT32
    host => STRING
    port => INT32
  error_code => INT16

Field	Description
group_id	The unique group id.

JoinGroup API (Key: 11):

Requests:

JoinGroup Request (Version: 0) => group_id session_timeout member_id protocol_type [group_protocols] 
  group_protocols => protocol_name protocol_metadata 
    protocol_name => STRING
    protocol_metadata => BYTES
  group_id => STRING
  session_timeout => INT32
  member_id => STRING
  protocol_type => STRING

Field	Description
group_id	The group id.
session_timeout	The coordinator considers the consumer dead if it receives no heartbeat after this timeout in ms.
member_id	The assigned consumer id or an empty string for a new consumer.
protocol_type	Unique name for class of protocols implemented by group
group_protocols	List of protocols that the member supports
protocol_name
protocol_metadata

Responses:

JoinGroup Response (Version: 0) => error_code generation_id group_protocol leader_id member_id [members] 
  members => member_id member_metadata 
    member_id => STRING
    member_metadata => BYTES
  error_code => INT16
  generation_id => INT32
  group_protocol => STRING
  leader_id => STRING
  member_id => STRING

Field	Description
group_id	The group id.
session_timeout	The coordinator considers the consumer dead if it receives no heartbeat after this timeout in ms.
member_id	The assigned consumer id or an empty string for a new consumer.
protocol_type	Unique name for class of protocols implemented by group
group_protocols	List of protocols that the member supports
protocol_name
protocol_metadata

Heartbeat API (Key: 12):

Requests:

Heartbeat Request (Version: 0) => group_id group_generation_id member_id 
  group_id => STRING
  group_generation_id => INT32
  member_id => STRING

Field	Description
group_id	The group id.
group_generation_id	The generation of the group.
member_id	The member id assigned by the group coordinator.

Responses:

Heartbeat Response (Version: 0) => error_code 
  error_code => INT16

Field	Description
group_id	The group id.
group_generation_id	The generation of the group.
member_id	The member id assigned by the group coordinator.

LeaveGroup API (Key: 13):

Requests:

LeaveGroup Request (Version: 0) => group_id member_id 
  group_id => STRING
  member_id => STRING

Field	Description
group_id	The group id.
member_id	The member id assigned by the group coordinator.

Responses:

LeaveGroup Response (Version: 0) => error_code 
  error_code => INT16

Field	Description
group_id	The group id.
member_id	The member id assigned by the group coordinator.

SyncGroup API (Key: 14):

Requests:

SyncGroup Request (Version: 0) => group_id generation_id member_id [group_assignment] 
  group_assignment => member_id member_assignment 
    member_id => STRING
    member_assignment => BYTES
  group_id => STRING
  generation_id => INT32
  member_id => STRING

Field	Description
group_id
generation_id
member_id
group_assignment
member_id
member_assignment

Responses:

SyncGroup Response (Version: 0) => error_code member_assignment 
  error_code => INT16
  member_assignment => BYTES

Field	Description
group_id
generation_id
member_id
group_assignment
member_id
member_assignment

DescribeGroups API (Key: 15):

Requests:

DescribeGroups Request (Version: 0) => [group_ids]

Field	Description
group_ids	List of groupIds to request metadata for (an empty groupId array will return empty group metadata).

Responses:

DescribeGroups Response (Version: 0) => [groups] 
  groups => error_code group_id state protocol_type protocol [members] 
    members => member_id client_id client_host member_metadata member_assignment 
      member_id => STRING
      client_id => STRING
      client_host => STRING
      member_metadata => BYTES
      member_assignment => BYTES
    error_code => INT16
    group_id => STRING
    state => STRING
    protocol_type => STRING
    protocol => STRING

Field	Description
group_ids	List of groupIds to request metadata for (an empty groupId array will return empty group metadata).

ListGroups API (Key: 16):

Requests:

ListGroups Request (Version: 0) =>

Field	Description

Responses:

ListGroups Response (Version: 0) => error_code [groups] 
  groups => group_id protocol_type 
    group_id => STRING
    protocol_type => STRING
  error_code => INT16

Field	Description