上章介绍了 dpos的运行原理机制: https://blog.csdn.net/weixin_41806245/article/details/80642086,俗话说的很好说和做是两个概念,为了加强对dpos的了解本章咱们实现的简单的dpos。(代码只为演示dpos)
因为大多数的底层链用go开发的较多,这里使用go来展示。不熟悉的可以自己去补课。
本章目的:
go 实现dpos
代码解析:
package main import ( "time" "encoding/hex" "math/rand" "log" "sort" "crypto/sha256" ) //定义区块结构体 type Block struct { Index int Timestamp string BPM int Hash string PrevHash string Delegate string } // 创建区块函数 func generateBlock(oldBlock Block, _BMP int, address string) (Block, error) { var newBlock Block t := time.Now() newBlock.Index = oldBlock.Index + 1 newBlock.Timestamp = t.String() newBlock.BPM = _BMP newBlock.PrevHash = oldBlock.Hash newBlock.Hash = createBlockHash(newBlock) newBlock.Delegate = address return newBlock, nil } //生成区块hash func createBlockHash(block Block) string { record := string(block.Index) + block.Timestamp + string(block.BPM) + block.PrevHash sha3 := sha256.New() sha3.Write([] byte(record)) hash := sha3.Sum(nil) return hex.EncodeToString(hash) } // 简单的检验区块函数 func isBlockValid(newBlock, oldBlock Block) bool{ if oldBlock.Index + 1 != newBlock.Index { return false } if newBlock.PrevHash != oldBlock.Hash { return false } return true } // 区块集合 var blockChain []Block // dpos里的超级节点结构体(受托人) type Trustee struct { name string votes int } type trusteeList [] Trustee // 下面的三个函数是为了排序使用,大家可以查下go的排序还是很强大的 func (_trusteeList trusteeList) Len() int { return len(_trusteeList) } func (_trusteeList trusteeList) Swap(i, j int){ _trusteeList[i], _trusteeList[j] = _trusteeList[j], _trusteeList[i] } func (_trusteeList trusteeList) Less(i, j int) bool { return _trusteeList[j].votes < _trusteeList[i].votes } // 选举获得投票数最高的前5节点作为超级节点,并打乱其顺序 func selectTrustee() ([]Trustee){ _trusteeList := [] Trustee { {"node1", rand.Intn(100)}, {"node2", rand.Intn(100)}, {"node3", rand.Intn(100)}, {"node4", rand.Intn(100)}, {"node5", rand.Intn(100)}, {"node6", rand.Intn(100)}, {"node7", rand.Intn(100)}, {"node8", rand.Intn(100)}, {"node9", rand.Intn(100)}, {"node10", rand.Intn(100)}, {"node11", rand.Intn(100)}, {"node12", rand.Intn(100)}, } sort.Sort(trusteeList(_trusteeList)) result := _trusteeList[:5] _trusteeList = result[1:] _trusteeList = append(_trusteeList, result[0]) log.Println("当前超级节点列表是", _trusteeList) return _trusteeList } func main() { t := time.Now() // init gensis block(创建创世块,真正的可不是这么简单的,这里只做流程实现) genesisBlock := Block{0, t.String(), 0, createBlockHash(Block{}), "", ""} blockChain = append(blockChain, genesisBlock) // 这里只是完成了一次dpos的写区块操作,eos真正的是每个节点实现6个区块,并且所有超级节点(21个)轮完,之后再做选举 var trustee Trustee for _, trustee = range selectTrustee() { _BPM := rand.Intn(100) blockHeight := len(blockChain) oldBlock := blockChain[blockHeight - 1] newBlock, err := generateBlock(oldBlock, _BPM, trustee.name) if err != nil { log.Println(err) continue } if isBlockValid(newBlock, oldBlock) { blockChain = append(blockChain, newBlock) log.Println("当前操作区块的节点是: ", trustee.name) log.Println("当前区块数量是: ", len(blockChain) - 1) log.Println("当前区块信息: ", blockChain[len(blockChain) - 1]) } } }
真正的区块交易信息、校验 ,选举可不是这么简单大概的过程是这样的希望对你学习区块链算法有所帮助,如有问题可以私信我。
好了本章结束, 下章咱们介绍 EOS高吞吐量的杀手锏BFT-DPoS