WriteTxnMarkers
This page encodes the smallest legal instance of the request and the response: numeric fields are zero, strings and byte arrays are empty, every array carries exactly one sample element, and any records field holds one empty 61-byte RecordBatch v2. Version 1 is a flexible version, so every struct is terminated by a uvarint tagged-field count and strings and arrays carry compact length-plus-one prefixes. Sizes below include the leading int32 size prefix.
- API key
- 27
- Encoded at
- v1
- Flexible versions
- 1+
- Headers
- req v2, resp v1
- Request versions
- 1
- Response versions
- 1
- Request size
- 41 bytes
- Response size
- 31 bytes
framerpc headerrequest bodyRecordBatchRecordresponse bodytagged_fields
Request
WriteTxnMarkersRequest v1, request header v2, 41 bytes on the wire
byte layout (41 bytes, 16 bytes per row)
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object tree
WriteTxnMarkersRequest message v1 [0x0000, 41B] +-- Frame [0x0000, 4B] length-delimited framing | +-- size int32 = 37 [0x0000, 4B] number of bytes that follow, patched after encoding +-- RequestHeader v2 [0x0004, 11B] common request header | +-- request_api_key int16 = 27 (WriteTxnMarkers) [0x0004, 2B] numeric id of the API being invoked | +-- request_api_version int16 = 1 [0x0006, 2B] version of the API being invoked | +-- correlation_id int32 = 0 [0x0008, 4B] echoed back by the broker in the response | +-- client_id nullable_string = "" (int16 len=0) [0x000c, 2B] always a non-flexible int16-prefixed string | +-- tagged_fields uvarint = 0 [0x000e, 1B] number of tagged fields in the header +-- WriteTxnMarkersRequest struct [0x000f, 26B] message body, version 1 +-- Markers []WritableTxnMarker = 1 element [0x000f, 25B] The transaction markers to be written. | +-- length uvarint = 2 (compact, n+1) [0x000f, 1B] one sample element follows | +-- WritableTxnMarker[0] WritableTxnMarker = struct [0x0010, 24B] | +-- ProducerId int64 = 0 [0x0010, 8B] The current producer ID. | +-- ProducerEpoch int16 = 0 [0x0018, 2B] The current epoch associated with the producer ID. | +-- TransactionResult bool = false [0x001a, 1B] The result of the transaction to write to the partitions (false = ABORT, tr... | +-- Topics []WritableTxnMarkerTopic = 1 element [0x001b, 8B] Each topic that we want to write transaction marker(s) for. | | +-- length uvarint = 2 (compact, n+1) [0x001b, 1B] one sample element follows | | +-- WritableTxnMarkerTopic[0] WritableTxnMarkerTopic = struct [0x001c, 7B] | | +-- Name string = "" (compact, len+1=1) [0x001c, 1B] The topic name. | | +-- PartitionIndexes []int32 = 1 element [0x001d, 5B] The indexes of the partitions to write transaction markers for. | | | +-- length uvarint = 2 (compact, n+1) [0x001d, 1B] one sample element follows | | | +-- int32[0] int32 = 0 [0x001e, 4B] | | +-- tagged_fields uvarint = 0 [0x0022, 1B] number of tagged fields in this struct | +-- CoordinatorEpoch int32 = 0 [0x0023, 4B] Epoch associated with the transaction state partition hosted by this transa... | +-- tagged_fields uvarint = 0 [0x0027, 1B] number of tagged fields in this struct +-- tagged_fields uvarint = 0 [0x0028, 1B] number of tagged fields in this struct
kafka message schema (.json)
{ "apiKey": 27, "type": "request", "listeners": ["broker"], "name": "WriteTxnMarkersRequest", // Version 0 was removed in Apache Kafka 4.0, Version 1 is the new baseline. // // Version 1 enables flexible versions. "validVersions": "1", "flexibleVersions": "1+", "fields": [ { "name": "Markers", "type": "[]WritableTxnMarker", "versions": "0+", "about": "The transaction markers to be written.", "fields": [ { "name": "ProducerId", "type": "int64", "versions": "0+", "entityType": "producerId", "about": "The current producer ID."}, { "name": "ProducerEpoch", "type": "int16", "versions": "0+", "about": "The current epoch associated with the producer ID." }, { "name": "TransactionResult", "type": "bool", "versions": "0+", "about": "The result of the transaction to write to the partitions (false = ABORT, true = COMMIT)." }, { "name": "Topics", "type": "[]WritableTxnMarkerTopic", "versions": "0+", "about": "Each topic that we want to write transaction marker(s) for.", "fields": [ { "name": "Name", "type": "string", "versions": "0+", "entityType": "topicName", "about": "The topic name." }, { "name": "PartitionIndexes", "type": "[]int32", "versions": "0+", "about": "The indexes of the partitions to write transaction markers for." } ]}, { "name": "CoordinatorEpoch", "type": "int32", "versions": "0+", "about": "Epoch associated with the transaction state partition hosted by this transaction coordinator." } ]} ] }
Response
WriteTxnMarkersResponse v1, response header v1, 31 bytes on the wire
byte layout (31 bytes, 16 bytes per row)
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WriteTxnMarkersResponse message v1 [0x0000, 31B] +-- Frame [0x0000, 4B] length-delimited framing | +-- size int32 = 27 [0x0000, 4B] number of bytes that follow, patched after encoding +-- ResponseHeader v1 [0x0004, 5B] common response header | +-- correlation_id int32 = 0 [0x0004, 4B] matches the correlation_id of the request | +-- tagged_fields uvarint = 0 [0x0008, 1B] number of tagged fields in the header +-- WriteTxnMarkersResponse struct [0x0009, 22B] message body, version 1 +-- Markers []WritableTxnMarkerResult = 1 element [0x0009, 21B] The results for writing makers. | +-- length uvarint = 2 (compact, n+1) [0x0009, 1B] one sample element follows | +-- WritableTxnMarkerResult[0] WritableTxnMarkerResult = struct [0x000a, 20B] | +-- ProducerId int64 = 0 [0x000a, 8B] The current producer ID in use by the transactional ID. | +-- Topics []WritableTxnMarkerTopicResult = 1 element [0x0012, 11B] The results by topic. | | +-- length uvarint = 2 (compact, n+1) [0x0012, 1B] one sample element follows | | +-- WritableTxnMarkerTopicResult[0] WritableTxnMarkerTopicResult = struct [0x0013, 10B] | | +-- Name string = "" (compact, len+1=1) [0x0013, 1B] The topic name. | | +-- Partitions []WritableTxnMarkerPartitionResult = 1 element [0x0014, 8B] The results by partition. | | | +-- length uvarint = 2 (compact, n+1) [0x0014, 1B] one sample element follows | | | +-- WritableTxnMarkerPartitionResult[0] WritableTxnMarkerPartitionResult = struct [0x0015, 7B] | | | +-- PartitionIndex int32 = 0 [0x0015, 4B] The partition index. | | | +-- ErrorCode int16 = 0 [0x0019, 2B] The error code, or 0 if there was no error. | | | +-- tagged_fields uvarint = 0 [0x001b, 1B] number of tagged fields in this struct | | +-- tagged_fields uvarint = 0 [0x001c, 1B] number of tagged fields in this struct | +-- tagged_fields uvarint = 0 [0x001d, 1B] number of tagged fields in this struct +-- tagged_fields uvarint = 0 [0x001e, 1B] number of tagged fields in this struct
kafka message schema (.json)
{ "apiKey": 27, "type": "response", "name": "WriteTxnMarkersResponse", "validVersions": "1", // Version 0 was removed in Apache Kafka 4.0, Version 1 is the new baseline. // // Version 1 enables flexible versions. "flexibleVersions": "1+", "fields": [ { "name": "Markers", "type": "[]WritableTxnMarkerResult", "versions": "0+", "about": "The results for writing makers.", "fields": [ { "name": "ProducerId", "type": "int64", "versions": "0+", "entityType": "producerId", "about": "The current producer ID in use by the transactional ID." }, { "name": "Topics", "type": "[]WritableTxnMarkerTopicResult", "versions": "0+", "about": "The results by topic.", "fields": [ { "name": "Name", "type": "string", "versions": "0+", "entityType": "topicName", "about": "The topic name." }, { "name": "Partitions", "type": "[]WritableTxnMarkerPartitionResult", "versions": "0+", "about": "The results by partition.", "fields": [ { "name": "PartitionIndex", "type": "int32", "versions": "0+", "about": "The partition index." }, { "name": "ErrorCode", "type": "int16", "versions": "0+", "about": "The error code, or 0 if there was no error." } ]} ]} ]} ] }