A RAFT Election implementation in Go. More information on RAFT can be found in this research paper and this video.

RAFT is a consensus based algorithm that produces consistent state through replicated logs and leader elections. Continuum has several uses for an election algorithm that produces guaranteed leaders for N-wise scalability and elimination of SPOF (Single Point of Failure). In the current design, both the Health Manager and the AuthServer will utilize an elected leader.

ci := graft.ClusterInfo{Name: "health_manager", Size: 3}
rpc, err := graft.NewNatsRpc(&nats.DefaultOptions)
handler := graft.NewChanHandler(make(chan StateChange), make(chan error))

node, err := graft.New(ci, handler, rpc, "/tmp/graft.log");

// ...

if node.State() == graft.LEADER {
  // Process as a LEADER
}

select {
  case sc := <- stateChangeChan:
    // Process a state change
  case err := <- errChan:
    // Process an error, log etc.
}

(The MIT License)

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