woop/consensus/consensus.go

// Consensus package implements the Cosi PBFT consensus
package consensus // consensus

import (
	"harmony-benchmark/p2p"
)

// Consensus data containing all info related to one consensus process
type Consensus struct {
	state ConsensusState
	// Signatures collected from validators
	commits map[string]string
	// Signatures collected from validators
	responses map[string]string
	// Actual block data to reach consensus on
	data string
	// List of validators
	validators []p2p.Peer
	// Leader
	leader p2p.Peer
	// private key of current node
	priKey string
	// Whether I am leader. False means I am validator
	IsLeader bool
}

// Consensus state enum for both leader and validator
// States for leader:
//     READY, ANNOUNCE_DONE, CHALLENGE_DONE, FINISHED
// States for validator:
//     READY, COMMIT_DONE, RESPONSE_DONE, FINISHED
type ConsensusState int

const (
	READY ConsensusState = iota
	ANNOUNCE_DONE
	COMMIT_DONE
	CHALLENGE_DONE
	RESPONSE_DONE
	FINISHED
)

// Returns string name for the ConsensusState enum
func (state ConsensusState) String() string {
	names := [...]string{
		"READY",
		"ANNOUNCE_DONE",
		"COMMIT_DONE",
		"CHALLENGE_DONE",
		"RESPONSE_DONE",
		"FINISHED"}

	if state < READY || state > RESPONSE_DONE {
		return "Unknown"
	}
	return names[state]
}

func InitConsensus(ip, port string, peers []p2p.Peer, leader p2p.Peer) Consensus {
	// The first Ip, port passed will be leader.
	consensus := Consensus{}
	peer := p2p.Peer{Port: port, Ip: ip}
	Peers := peers
	leaderPeer := leader
	if leaderPeer == peer {
		consensus.IsLeader = true
	} else {
		consensus.IsLeader = false
	}
	consensus.commits = make(map[string]string)
	consensus.responses = make(map[string]string)
	consensus.leader = leaderPeer
	consensus.validators = Peers

	consensus.priKey = ip + ":" + port // use ip:port as unique key for now
	return consensus
}