hyperledger fabric的pbft算法go语言实现代码

以下是Hyperledger Fabric的PBFT算法Go语言实现代码：

package pbft

import (
	"crypto/sha256"
	"encoding/hex"
	"encoding/json"
	"fmt"
	"sync"
)

const (
	// PbftPhaseNotStarted represents the state where PBFT is not started
	PbftPhaseNotStarted = iota
	// PbftPhasePrePrepare represents the state where PBFT is in the pre-prepare phase
	PbftPhasePrePrepare
	// PbftPhasePrepare represents the state where PBFT is in the prepare phase
	PbftPhasePrepare
	// PbftPhaseCommit represents the state where PBFT is in the commit phase
	PbftPhaseCommit
)

// PbftMessage represents a message in the PBFT algorithm
type PbftMessage struct {
	Phase       int
	SequenceNum int
	View        int
	Digest      string
	Block       []byte
	ReplicaID   int
}

// Pbft represents a PBFT instance
type Pbft struct {
	mux         sync.Mutex
	replicaID   int
	view        int
	sequenceNum int
	state       int
	digest      string
	block       []byte
	messages    map[string]PbftMessage
}

// NewPbft creates a new PBFT instance with the specified replica ID
func NewPbft(replicaID int) *Pbft {
	return &Pbft{
		replicaID: replicaID,
		view:      0,
		state:     PbftPhaseNotStarted,
		messages:  make(map[string]PbftMessage),
	}
}

// Start starts the PBFT algorithm with the specified block
func (p *Pbft) Start(block []byte) {
	p.mux.Lock()
	defer p.mux.Unlock()

	// Set the initial state
	p.view = 0
	p.sequenceNum = 1
	p.state = PbftPhasePrePrepare
	p.block = block

	// Compute the digest of the block
	digest := sha256.Sum256(block)
	p.digest = hex.EncodeToString(digest[:])

	// Create and broadcast the pre-prepare message
	prePrepareMsg := PbftMessage{
		Phase:       PbftPhasePrePrepare,
		SequenceNum: p.sequenceNum,
		View:        p.view,
		Digest:      p.digest,
		Block:       p.block,
		ReplicaID:   p.replicaID,
	}
	p.broadcast(prePrepareMsg)
}

// HandleMessage handles an incoming PBFT message
func (p *Pbft) HandleMessage(msg []byte) {
	p.mux.Lock()
	defer p.mux.Unlock()

	// Parse the message
	var pbftMsg PbftMessage
	err := json.Unmarshal(msg, &pbftMsg)
	if err != nil {
		fmt.Printf("Failed to parse PBFT message: %s\n", err)
		return
	}

	// Check if we have already seen this message
	key := p.getMessageKey(pbftMsg)
	if _, ok := p.messages[key]; ok {
		return
	}

	// Add the message to our list of seen messages
	p.messages[key] = pbftMsg

	switch p.state {
	case PbftPhasePrePrepare:
		p.handlePrePrepare(pbftMsg)
	case PbftPhasePrepare:
		p.handlePrepare(pbftMsg)
	case PbftPhaseCommit:
		p.handleCommit(pbftMsg)
	}
}

// broadcast broadcasts a PBFT message to all other replicas
func (p *Pbft) broadcast(msg PbftMessage) {
	// TODO: implement broadcast
}

// handlePrePrepare handles a pre-prepare message
func (p *Pbft) handlePrePrepare(msg PbftMessage) {
	if msg.View != p.view || msg.SequenceNum != p.sequenceNum || msg.Digest != p.digest {
		return
	}

	// Create and broadcast the prepare message
	prepareMsg := PbftMessage{
		Phase:       PbftPhasePrepare,
		SequenceNum: p.sequenceNum,
		View:        p.view,
		Digest:      p.digest,
		Block:       p.block,
		ReplicaID:   p.replicaID,
	}
	p.broadcast(prepareMsg)

	// Update state
	p.state = PbftPhasePrepare
}

// handlePrepare handles a prepare message
func (p *Pbft) handlePrepare(msg PbftMessage) {
	if msg.View != p.view || msg.SequenceNum != p.sequenceNum || msg.Digest != p.digest {
		return
	}

	// Update state
	p.state = PbftPhaseCommit

	// Create and broadcast the commit message
	commitMsg := PbftMessage{
		Phase:       PbftPhaseCommit,
		SequenceNum: p.sequenceNum,
		View:        p.view,
		Digest:      p.digest,
		Block:       p.block,
		ReplicaID:   p.replicaID,
	}
	p.broadcast(commitMsg)
}

// handleCommit handles a commit message
func (p *Pbft) handleCommit(msg PbftMessage) {
	if msg.View != p.view || msg.SequenceNum != p.sequenceNum || msg.Digest != p.digest {
		return
	}

	// TODO: validate the commit message
}

// getMessageKey returns a unique key for a PBFT message
func (p *Pbft) getMessageKey(msg PbftMessage) string {
	return fmt.Sprintf("%d:%d:%s:%d", msg.View, msg.SequenceNum, msg.Digest, msg.ReplicaID)
}

注意，上述代码只是一个简单的示例，需要根据实际情况进行修改和扩展。另外，这里的广播机制还没有实现，需要根据实际情况选择适当的广播方式。