elasticsearch 5.2.2 学习笔记之源码阅读6-索引流程总览之删除索引

elasticsearch 5.2.2 学习笔记之源码阅读6-索引流程总览之删除索引

概述

• 参考
  • https://github.com/elastic/elasticsearch/tree/v5.2.2
  • https://blog.youkuaiyun.com/undergrowth/article/details/82851401
  • https://blog.youkuaiyun.com/undergrowth/article/details/82885628

索引流程总览之删除索引 接上一篇 elasticsearch 5.2.2 学习笔记之源码阅读5-索引流程总览之添加索引类型数据

• 删除索引
  • postman delete http://localhost:9200/testindex

核心接口与类

• 前置加载过程与 https://blog.youkuaiyun.com/undergrowth/article/details/82851401 类似,主要看各个Action的不同
• 本文涉及到的Action
  • 删除索引
    • DeleteIndexAction/RestDeleteIndexAction/TransportDeleteIndexAction
• 使用AbstractComponent和AbstractLifecycleComponent管理核心组件的配置与生命周期
  • AbstractComponent
    • MetaDataDeleteIndexService(负责提交删除索引请求)
    • AllocationService(管理集群中节点的分片行为)
    • DestructiveOperations(辅助操作类)
• IndexComponent
  • AbstractIndexComponent
    • IndexService(负责索引相关功能)
    • MapperService(负责映射相关功能)
• ClusterState(管理集群的状态以及各种元信息存放)
• MetaData(存放集群元信息)
• IndexMetaData(单个索引的元信息)
  • settings/mappings/aliases/numberOfShards/numberOfReplicas等信息
• RoutingTable(存放集群范围内所有索引的路由信息)
• TransportAction
  • HandledTransportAction(负责在传输层注册处理器处理消息)
    • TransportMasterNodeAction(封装需要在master节点才能操作的行为)
      • TransportDeleteIndexAction(删除索引Action)

以删除索引为例讲解加载过程

• postman delete http://localhost:9200/testindex
  • 前置加载过程参看 https://blog.youkuaiyun.com/undergrowth/article/details/82851401
  • 分别来看DeleteIndexAction/RestDeleteIndexAction/TransportDeleteIndexAction三者间的消息扭转
    • 通过RestDeleteIndexAction#prepareRequest创建DeleteIndexRequest请求,借助NodeClient#executeLocally扭转到TransportDeleteIndexAction#doExecute
    • 创建AsyncSingleAction执行删除删除索引请求,进而回调TransportMasterNodeAction#masterOperation和TransportDeleteIndexAction#masterOperation,依赖org.elasticsearch.cluster.metadata.MetaDataDeleteIndexService#deleteIndices完成相关索引信息的更新与操作
    • 从集群中删除索引信息MetaDataDeleteIndexService#deleteIndices,例如进行快照检查SnapshotsService.checkIndexDeletion,从路由表中删除routingTableBuilder.remove,集群数据块中删除clusterBlocksBuilder.removeIndexBlocks,元信息中删除metaDataBuilder.remove,同时数据重新分片allocationService.reroute