[HBASE-10909] Abstract out ZooKeeper usage in HBase - phase 1

• Type: Umbrella
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.99.0
• Fix Version/s: 0.99.0
• Component/s: Consensus, Zookeeper
• Assignee: Mikhail Antonov
• Reporter: Mikhail Antonov
• Created: 04/Apr/14 07:27
• Updated: 04/Apr/18 23:05
• Resolved: 08/Sep/14 01:57

Description

As some sort of follow-up or initial step towards HBASE-10296.
Whatever consensus algorithm/library may be the chosen, perhaps one of first practical steps towards this goal would be to better abstract ZK-related API and details, which are now throughout the codebase (mostly leaked throuth ZkUtil, ZooKeeperWatcher and listeners).

This jira is umbrella for relevant subtasks. Design doc is attached, for comments/questions there's a google doc linked.

This issue covers phase-1 of abstraction work, which includes:

• infrastructure to support pluggable coordinated state managers
• abstraction of region opening/closing/splitting/merging operations
• abstraction of admin operation handlers like CreateTableHandler
• abstract ZKTable (reworked it to interface and implementation, allowing for new system tables-based impl to be developed)
• WAL splitting abstraction.

Issue Links

• is related to: HBASE-11059 ZK-less region assignment
• is related to: HBASE-10856 Prep for 1.0
• is required by: HBASE-10296 Replace ZK with a consensus lib(paxos,zab or raft) running within master processes to provide better master failover performance and state consistency
• relates to: HBASE-9864 Notifications bus for use by cluster members keeping up-to-date on changes
• relates to: HBASE-11241 Support for multiple active HMaster replicas
• links to: Design document for abstracting Zookeeper APIs

Sub-Tasks

• Decouple HLogSplitterHandler from ZooKeeper: Closed
• Decouple region closing (HM and HRS) from ZK: Closed
• Decouple region opening (HM and HRS) from ZK: Closed
• Decouple Split Transaction from Zookeeper: Closed
• Infrastructure for pluggable consensus service: Closed
• Decouple region merging from ZooKeeper: Closed
• Abstract HM admin table handlers from ZK: Closed
• Abstract WAL splitting from ZK: Closed
• Server interface should have method getConsensusProvider(): Closed
• Split ZKTable into interface and implementation: Closed
• LocalHBaseCluster should create ConsensusProvider per each server: Closed