raft

Raft consensus implementation in Rust

This project is intended to fast prototyping of the distributed software. It is based on Diego Ongaro's dissertation. Full information about the Raft you can get at its official site.

These Raft features are implemented

• Leadership

  • election
  • status watcher

• Operation log support

  • creation
  • replication
    • basic
    • forced

• Replicated state machine support

• Cluster membership changes

  • add server (basic support)

• Client RPC (partial):

  • add server
  • add data

These features should be implemented to meet full Raft requirements

• Cluster membership changes

  • add server (round-based implementation with TIMEOUT-reply to clients)
  • remove server
    • transfer leadership

• Client RPC

  • remove server
  • session support (for proper duplicate request handling)
  • read(query) RPC

• Log compaction

Project designed to be modular and independent of the actual implementations.

These modules must be implemented in order to run Raft Node

• Operation log - supports operation log entries processing and calculating parameters (index, term, etc).
• Replicated state machine - supports operations with replicated state machine (like 'append new entry').
• Peer request handler - Module responsible for communication between Raft Nodes.
• Client request handler - this module responsible for client communication. Module handles request like 'add new data' or 'add server'.
• Cluster - defines cluster membership and quorum rules.
• Election timer - calculates duration to the next elections.
• Node limits - defines node timeouts and limits (e.g.: max request data size)
• Node state saver - responsible for node state persistence

Raft Modules implementations

Basic (example) implementations were separated in the subproject

Test cases and examples

Assembled Raft Node server can be found here, with client example

Plenty of different test configurations and cases can be found in this subproject.