Kafka Queue: 完成 alterShareGroupOffsets Api

支持重置偏移量，换句话说也就是支持消息的重放；classic group支持按照偏移量或者时间重置到最新、最老以及指定时间的偏移量

PR list

命令

kafka-share-groups.sh --bootstrap-server localhost:9092 --group S1 --topic T1 --reset-offsets --to-earliest --execute

SPSO

Share group引入了SPSO(Share-partition start offset) 的概念，可以理解为当前第一个被客户端拉走，但是未被提交的record batches，这个功能主要就是对SPSO进行操作

新增请求与响应

请求体

json 复制代码

{
  "apiKey": 91,
  "type": "request",
  "listeners": ["broker"],
  "name": "AlterShareGroupOffsetsRequest",
  "validVersions": "0",
  "flexibleVersions": "0+",
  "fields": [
    { "name": "GroupId", "type": "string", "versions": "0+", "entityType": "groupId",
      "about": "The group identifier." },
    { "name": "Topics", "type": "[]AlterShareGroupOffsetsRequestTopic", "versions": "0+",
      "about": "The topics to alter offsets for.",  "fields": [
        { "name": "TopicName", "type": "string", "versions": "0+", "entityType": "topicName", "mapKey": true,
          "about": "The topic name." },
        { "name": "Partitions", "type": "[]AlterShareGroupOffsetsRequestPartition", "versions": "0+",
          "about": "Each partition to alter offsets for.", "fields": [
            { "name": "PartitionIndex", "type": "int32", "versions": "0+",
              "about": "The partition index." },
            { "name": "StartOffset", "type": "int64", "versions": "0+",
              "about": "The share-partition start offset." }
          ]}
      ]}
  ]
}

响应体

json 复制代码

{
  "apiKey": 91,
  "type": "response",
  "name": "AlterShareGroupOffsetsResponse",
  "validVersions": "0",
  "flexibleVersions": "0+",
  // Supported errors:
  // - GROUP_AUTHORIZATION_FAILED (version 0+)
  // - TOPIC_AUTHORIZATION_FAILED (version 0+)
  // - NOT_COORDINATOR (version 0+)
  // - COORDINATOR_NOT_AVAILABLE (version 0+)
  // - COORDINATOR_LOAD_IN_PROGRESS (version 0+)
  // - GROUP_ID_NOT_FOUND (version 0+)
  // - NON_EMPTY_GROUP (version 0+)
  // - KAFKA_STORAGE_ERROR (version 0+)
  // - INVALID_REQUEST (version 0+)
  // - UNKNOWN_SERVER_ERROR (version 0+)
  "fields": [
    { "name": "ThrottleTimeMs", "type": "int32", "versions": "0+",
      "about": "The duration in milliseconds for which the request was throttled due to a quota violation, or zero if the request did not violate any quota." },
    { "name": "ErrorCode", "type": "int16", "versions": "0+",
      "about": "The top-level error code, or 0 if there was no error." },
    { "name": "ErrorMessage", "type": "string", "versions": "0+", "nullableVersions": "0+", "default": "null",
      "about": "The top-level error message, or null if there was no error." },
    { "name": "Responses", "type": "[]AlterShareGroupOffsetsResponseTopic", "versions": "0+",
      "about": "The results for each topic.", "fields": [
        { "name": "TopicName", "type": "string", "versions": "0+", "entityType": "topicName", "mapKey": true,
          "about": "The topic name." },
        { "name": "TopicId", "type": "uuid", "versions": "0+",
          "about": "The unique topic ID." },
        { "name": "Partitions", "type": "[]AlterShareGroupOffsetsResponsePartition", "versions": "0+", "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." },
          { "name": "ErrorMessage", "type": "string", "versions": "0+", "nullableVersions": "0+", "default": "null",
            "about": "The error message, or null if there was no error." }
        ]}
      ]}
  ]
}

主要过程

只有空的消费组支持重置
重置过程中，会触发一次Group Coordinator初始化ShareGroupState的过程
Group Coordinator向Share Coordinator持久化一条InitialzeShareGroupState的请求，持久化写入__share_group_state内部Topic

过程中遇到的问题

1、代码习惯、缩进以及语言风格的问题；

2、参数校验以及异常处理，各种情况下的参数抛出，比如下面这些场景

3、因为写API的过程中参考了ConsumerGroup的实现，没有注意到错误码的处理过程，实际上对于经典消费组重置偏移量的过程，是通过提交一个新的CommitOffset 请求来实现的，并没有所为顶层错误码的概念；但是后在AlterShareGroupOffsetsResponse的响应体存在顶层的异常ErrorCode与ErrorMessage，但是实做过程中没有处理并封装到各个分区的响应中。后来AJ写了一个follow-up完成了这块：https://github.com/apache/kafka/pull/20049/files