标签：sls big qpi 初始 bad 二进制 roo get 工作量证明
目录：一.初始化区块链
1.代码结构
2. 定义区块结构与方法
3. 定义区块链结构与方法
4. 帮助库代码
5. 测试生成区块与初始化区块链
6. 测试代码
二. POW挖矿实现
1.代码结构
2. 定义pow算法实现
3. 修改区块的生成方式(从自定义到挖矿)
4. 测试代码，测试挖矿
5.验证区块有效性
一.初始化区块链
1. 代码结构
Block.go :定义区块结构与方法
BlockChain.go :定义区块链结构与方法
help.go :将常用代码块进行封装，形成帮助库
main.go:测试代码
2.定义区块结构与方法
package BLC
import (
"time"
"strconv"
"bytes"
"crypto/sha256"
)
//定义区块
type Block struct {
//1.区块高度，也就是区块的编号，第几个区块
Height int64
//2.上一个区块的Hash值
PreBlockHash []byte
//3.交易数据（最终都属于transaction 事务）
Data []byte
//4.创建时间的时间戳
TimeStamp int64
//5.当前区块的Hash值
Hash []byte
//6.Nonce 随机数，用于验证工作量证明
Nonce int64
}
//定义区块生成Hash的方法
func (block *Block) SetHash() {
//1.将Height 转换为字节数组 []byte
heightBytes := IntToHex(block.Height)
//2.将TimeStamp 转换为字节数组 []byte
//2.1 将Int64的TimeStamp 转换成二进制
timeString := strconv.FormatInt(block.TimeStamp, 2)
//2.2 将二进制字符串转成字节数组
timeBytes := []byte(timeString)
//3.拼接所有属性,形成一个二维的byte数组
blockBytes := bytes.Join([][]byte{heightBytes, block.PreBlockHash, block.Data, timeBytes, block.Hash}, []byte{})
//4.生成Hash
hash := sha256.Sum256(blockBytes)
block.Hash = hash[:]
}
//1. 创建新的区块
func NewBlock(data string, height int64, PreBlockHash []byte) *Block {
//创建区块
block := &Block{
height,
PreBlockHash,
[]byte(data),
time.Now().Unix(),
nil,
0,
}
//设置Hash
block.SetHash()
return block
}
//2.生成创世区块
func CreateGenesisBlock(data string) *Block {
return NewBlock(data, 1, []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0})
}3.定义区块链与方法
package BLC
type BlockChain struct {
Blocks []*Block //存储有序的区块
}
func (blc *BlockChain)AddBlockChain(data string,height int64,preHash []byte){
//创建新区块
newBlock := NewBlock(data,height,preHash)
//往链中添加区块
blc.Blocks=append(blc.Blocks,newBlock)
}
//1.创建带有创世区块的区块链
func CreateBlockChainWithGenesisBlock() *BlockChain {
//创建创世区块
genesisBlock := CreateGenesisBlock("Genesis Data..")
//返回区块链对象
return &BlockChain{[]*Block{genesisBlock}}
}4.帮助代码库
package BLC
import (
"bytes"
"encoding/binary"
"log"
)
//将int64转换为字节数组
func IntToHex(num int64) []byte {
buff := new(bytes.Buffer)
err := binary.Write(buff, binary.BigEndian, num)
if err != nil {
log.Panic(err)
}
return buff.Bytes()
}5.测试代码
package main
import (
"publicChain/BLC"
"fmt"
)
func main() {
//创建创世区块
blockChain := BLC.CreateBlockChainWithGenesisBlock()
//创建新的区块
blockChain.AddBlockChain("Send $100 to Bruce", blockChain.Blocks[len(blockChain.Blocks)-1].Height+1, blockChain.Blocks[len(blockChain.Blocks)-1].Hash)
blockChain.AddBlockChain("Send $200 to Apple", blockChain.Blocks[len(blockChain.Blocks)-1].Height+1, blockChain.Blocks[len(blockChain.Blocks)-1].Hash)
blockChain.AddBlockChain("Send $300 to Alice", blockChain.Blocks[len(blockChain.Blocks)-1].Height+1, blockChain.Blocks[len(blockChain.Blocks)-1].Hash)
blockChain.AddBlockChain("Send $400 to Bob", blockChain.Blocks[len(blockChain.Blocks)-1].Height+1, blockChain.Blocks[len(blockChain.Blocks)-1].Hash)
fmt.Printf("创建的区块链为:\t%v\n", blockChain)
fmt.Printf("区块链存储的区块为:\t%v\n", blockChain.Blocks)
fmt.Printf("第二个区块的数据信息(交易信息)为:\t%v\n", string(blockChain.Blocks[1].Data))
}结果显示
二. POW挖矿实现
1.代码结构
多出的ProofOfWork.go用于实现挖矿
2. 定义pow算法实现
ProofOfWork.go
package BLC
import (
"math/big"
"bytes"
"crypto/sha256"
"fmt"
"time"
)
type ProofOfWork struct {
Block *Block //当前要验证的区块
target *big.Int //大数存储，区块难度
}
//数据拼接，返回字节数组
func (pow *ProofOfWork) prePareData(nonce int) []byte {
data := bytes.Join(
[][]byte{
pow.Block.PreBlockHash,
pow.Block.Data,
IntToHex(pow.Block.TimeStamp),
IntToHex(int64(targetBit)),
IntToHex(int64(nonce)),
IntToHex(int64(pow.Block.Height)),
},
[]byte{},
)
return data
}
//256位Hash里面至少要有16个零0000 0000 0000 0000
const targetBit = 16
func (proofOfWork *ProofOfWork) Run(num int64) ([]byte, int64) {
//3.判断Hash的有效性，如果满足条件循环体
nonce := 0
var hashInt big.Int //存储新生成的hash值
var hash [32]byte
for {
//1. 将Block的属性拼接成字节数组
databytes := proofOfWork.prePareData(nonce)
//2.生成Hash
hash = sha256.Sum256(databytes)
fmt.Printf("挖矿中..%x\n", hash)
//3. 将hash存储至hashInt
hashInt.SetBytes(hash[:])
//4.判断hashInt是否小于Block里面的target
// Cmp compares x and y and returns:
//
// -1 if x < y
// 0 if x == y
// +1 if x > y
//需要hashInt(y)小于设置的target(x)
if proofOfWork.target.Cmp(&hashInt) == 1 {
//fmt.Println("挖矿成功", hashInt)
fmt.Printf("第%d个区块，挖矿成功:%x\n",num,hash)
fmt.Println(time.Now())
time.Sleep(time.Second * 2)
break
}
nonce ++
}
return hash[:], int64(nonce)
}
//创建新的工作量证明对象
func NewProofOfWork(block *Block) *ProofOfWork {
/*1.创建初始值为1的target
0000 0001
8 - 2
*/
target := big.NewInt(1)
//2.左移256-targetBit
target = target.Lsh(target, 256-targetBit)
return &ProofOfWork{block, target}
}3. 修改区块的生成方式(从自定义到挖矿)
Block.go
package BLC
import (
"time"
)
//定义区块
type Block struct {
//1.区块高度，也就是区块的编号，第几个区块
Height int64
//2.上一个区块的Hash值
PreBlockHash []byte
//3.交易数据（最终都属于transaction 事务）
Data []byte
//4.创建时间的时间戳
TimeStamp int64
//5.当前区块的Hash值
Hash []byte
//6.Nonce 随机数，用于验证工作量证明
Nonce int64
}
//1. 创建新的区块
func NewBlock(data string, height int64, PreBlockHash []byte) *Block {
//创建区块
block := &Block{
height,
PreBlockHash,
[]byte(data),
time.Now().Unix(),
nil,
0,
}
//调用工作量证明的方法，并且返回有效的Hash和Nonce值
//创建pow对象
pow := NewProofOfWork(block)
//挖矿验证
hash, nonce := pow.Run(height)
block.Hash = hash[:]
block.Nonce = nonce
return block
}
//2.生成创世区块
func CreateGenesisBlock(data string) *Block {
return NewBlock(data, 1, []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0})
}4. 测试代码，测试挖矿
main.go
package main
import (
"publicChain/part2-工作量证明/BLC"
"fmt"
)
func main() {
fmt.Println("开始挖矿")
//创建创世区块
blockChain := BLC.CreateBlockChainWithGenesisBlock()
//创建新的区块
blockChain.AddBlockChain("Send $100 to Bruce", blockChain.Blocks[len(blockChain.Blocks)-1].Height+1, blockChain.Blocks[len(blockChain.Blocks)-1].Hash)
blockChain.AddBlockChain("Send $200 to Apple", blockChain.Blocks[len(blockChain.Blocks)-1].Height+1, blockChain.Blocks[len(blockChain.Blocks)-1].Hash)
blockChain.AddBlockChain("Send $300 to Alice", blockChain.Blocks[len(blockChain.Blocks)-1].Height+1, blockChain.Blocks[len(blockChain.Blocks)-1].Hash)
blockChain.AddBlockChain("Send $400 to Bob", blockChain.Blocks[len(blockChain.Blocks)-1].Height+1, blockChain.Blocks[len(blockChain.Blocks)-1].Hash)
fmt.Printf("创建的区块链为:\t%v\n", blockChain)
fmt.Printf("区块链存储的区块为:\t%v\n", blockChain.Blocks)
fmt.Printf("第二个区块的数据信息(交易信息)为:\t%v\n", string(blockChain.Blocks[1].Data))
fmt.Printf("第二个区块的随机数为:\t%v\n", blockChain.Blocks[1].Nonce)
}测试结果
共计对五个区块进行挖矿，结果如上
5.验证区块有效性
ProofOfWork.go
//判断挖矿得到的区块是否有效
func (proofOfWork *ProofOfWork) IsValid() bool {
//1.proofOfWork.Block.Hash
//2.proofOfWork.Target
var hashInt big.Int
hashInt.SetBytes(proofOfWork.Block.Hash)
if proofOfWork.target.Cmp(&hashInt) == 1 {
return true
}
return false
}测试代码:
main.go
//通过POW挖出新的区块block
block := BLC.NewBlock("Send $500 to Tom", blockChain.Blocks[len(blockChain.Blocks)-1].Height+1, blockChain.Blocks[len(blockChain.Blocks)-1].Hash)
//手动将该区块添加至区块链中
blockChain.Blocks = append(blockChain.Blocks, block)
//创建一个工作量证明对象
proofOfWork := BLC.NewProofOfWork(block)
//判断该区块是否合法有效
fmt.Println(proofOfWork.IsValid())测试结果:
第六个区块是我们新创建的区块，返回值为true，验证有效
参考资料:
区块链共识算法-POW: https://www.jianshu.com/p/b23cbafbbad2
标签：sls big qpi 初始 bad 二进制 roo get 工作量证明
原文地址：http://blog.51cto.com/clovemfong/2149933
