目錄：
創(chuàng)新互聯(lián)服務(wù)項(xiàng)目包括保康網(wǎng)站建設(shè)、?？稻W(wǎng)站制作、?？稻W(wǎng)頁制作以及?？稻W(wǎng)絡(luò)營銷策劃等。多年來，我們專注于互聯(lián)網(wǎng)行業(yè)，利用自身積累的技術(shù)優(yōu)勢、行業(yè)經(jīng)驗(yàn)、深度合作伙伴關(guān)系等，向廣大中小型企業(yè)、政府機(jī)構(gòu)等提供互聯(lián)網(wǎng)行業(yè)的解決方案，保康網(wǎng)站推廣取得了明顯的社會效益與經(jīng)濟(jì)效益。目前，我們服務(wù)的客戶以成都為中心已經(jīng)輻射到保康省份的部分城市，未來相信會繼續(xù)擴(kuò)大服務(wù)區(qū)域并繼續(xù)獲得客戶的支持與信任！
一.初始化區(qū)塊鏈
1.代碼結(jié)構(gòu)
2. 定義區(qū)塊結(jié)構(gòu)與方法
3. 定義區(qū)塊鏈結(jié)構(gòu)與方法
4. 幫助庫代碼
5. 測試生成區(qū)塊與初始化區(qū)塊鏈
6. 測試代碼
二. POW挖礦實(shí)現(xiàn)
1.代碼結(jié)構(gòu)
2. 定義pow算法實(shí)現(xiàn)
3. 修改區(qū)塊的生成方式(從自定義到挖礦)
4. 測試代碼，測試挖礦
5.驗(yàn)證區(qū)塊有效性
一.初始化區(qū)塊鏈
1. 代碼結(jié)構(gòu)
Block.go :定義區(qū)塊結(jié)構(gòu)與方法
BlockChain.go :定義區(qū)塊鏈結(jié)構(gòu)與方法
help.go :將常用代碼塊進(jìn)行封裝，形成幫助庫
main.go:測試代碼
2.定義區(qū)塊結(jié)構(gòu)與方法
重慶分公司
重慶分公司
package BLC
import (
"time"
"strconv"
"bytes"
"crypto/sha256"
)
//定義區(qū)塊
type Block struct {
//1.區(qū)塊高度，也就是區(qū)塊的編號，第幾個區(qū)塊
Height int64
//2.上一個區(qū)塊的Hash值
PreBlockHash []byte
//3.交易數(shù)據(jù)（最終都屬于transaction 事務(wù)）
Data []byte
//4.創(chuàng)建時間的時間戳
TimeStamp int64
//5.當(dāng)前區(qū)塊的Hash值
Hash []byte
//6.Nonce 隨機(jī)數(shù)，用于驗(yàn)證工作量證明
Nonce int64
}
//定義區(qū)塊生成Hash的方法
func (block *Block) SetHash() {
//1.將Height 轉(zhuǎn)換為字節(jié)數(shù)組 []byte
heightBytes := IntToHex(block.Height)
//2.將TimeStamp 轉(zhuǎn)換為字節(jié)數(shù)組 []byte
//2.1 將Int64的TimeStamp 轉(zhuǎn)換成二進(jìn)制
timeString := strconv.FormatInt(block.TimeStamp, 2)
//2.2 將二進(jìn)制字符串轉(zhuǎn)成字節(jié)數(shù)組
timeBytes := []byte(timeString)
//3.拼接所有屬性,形成一個二維的byte數(shù)組
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. 創(chuàng)建新的區(qū)塊
func NewBlock(data string, height int64, PreBlockHash []byte) *Block {
//創(chuàng)建區(qū)塊
block := &Block{
height,
PreBlockHash,
[]byte(data),
time.Now().Unix(),
nil,
0,
}
//設(shè)置Hash
block.SetHash()
return block
}
//2.生成創(chuàng)世區(qū)塊
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.定義區(qū)塊鏈與方法
package BLC
type BlockChain struct {
Blocks []*Block //存儲有序的區(qū)塊
}
func (blc *BlockChain)AddBlockChain(data string,height int64,preHash []byte){
//創(chuàng)建新區(qū)塊
newBlock := NewBlock(data,height,preHash)
//往鏈中添加區(qū)塊
blc.Blocks=append(blc.Blocks,newBlock)
}
//1.創(chuàng)建帶有創(chuàng)世區(qū)塊的區(qū)塊鏈
func CreateBlockChainWithGenesisBlock() *BlockChain {
//創(chuàng)建創(chuàng)世區(qū)塊
genesisBlock := CreateGenesisBlock("Genesis Data..")
//返回區(qū)塊鏈對象
return &BlockChain{[]*Block{genesisBlock}}
}4.幫助代碼庫
package BLC
import (
"bytes"
"encoding/binary"
"log"
)
//將int64轉(zhuǎn)換為字節(jié)數(shù)組
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.測試代碼
package main
import (
"publicChain/BLC"
"fmt"
)
func main() {
//創(chuàng)建創(chuàng)世區(qū)塊
blockChain := BLC.CreateBlockChainWithGenesisBlock()
//創(chuàng)建新的區(qū)塊
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("創(chuàng)建的區(qū)塊鏈為:\t%v\n", blockChain)
fmt.Printf("區(qū)塊鏈存儲的區(qū)塊為:\t%v\n", blockChain.Blocks)
fmt.Printf("第二個區(qū)塊的數(shù)據(jù)信息(交易信息)為:\t%v\n", string(blockChain.Blocks[1].Data))
}結(jié)果顯示
二. POW挖礦實(shí)現(xiàn)
1.代碼結(jié)構(gòu)
多出的ProofOfWork.go用于實(shí)現(xiàn)挖礦
2. 定義pow算法實(shí)現(xiàn)
ProofOfWork.go
package BLC
import (
"math/big"
"bytes"
"crypto/sha256"
"fmt"
"time"
)
type ProofOfWork struct {
Block *Block //當(dāng)前要驗(yàn)證的區(qū)塊
target *big.Int //大數(shù)存儲，區(qū)塊難度
}
//數(shù)據(jù)拼接，返回字節(jié)數(shù)組
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個零0000 0000 0000 0000
const targetBit = 16
func (proofOfWork *ProofOfWork) Run(num int64) ([]byte, int64) {
//3.判斷Hash的有效性，如果滿足條件循環(huán)體
nonce := 0
var hashInt big.Int //存儲新生成的hash值
var hash [32]byte
for {
//1. 將Block的屬性拼接成字節(jié)數(shù)組
databytes := proofOfWork.prePareData(nonce)
//2.生成Hash
hash = sha256.Sum256(databytes)
fmt.Printf("挖礦中..%x\n", hash)
//3. 將hash存儲至hashInt
hashInt.SetBytes(hash[:])
//4.判斷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)小于設(shè)置的target(x)
if proofOfWork.target.Cmp(&hashInt) == 1 {
//fmt.Println("挖礦成功", hashInt)
fmt.Printf("第%d個區(qū)塊，挖礦成功:%x\n",num,hash)
fmt.Println(time.Now())
time.Sleep(time.Second * 2)
break
}
nonce ++
}
return hash[:], int64(nonce)
}
//創(chuàng)建新的工作量證明對象
func NewProofOfWork(block *Block) *ProofOfWork {
/*1.創(chuàng)建初始值為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. 修改區(qū)塊的生成方式(從自定義到挖礦)
Block.go
package BLC
import (
"time"
)
//定義區(qū)塊
type Block struct {
//1.區(qū)塊高度，也就是區(qū)塊的編號，第幾個區(qū)塊
Height int64
//2.上一個區(qū)塊的Hash值
PreBlockHash []byte
//3.交易數(shù)據(jù)（最終都屬于transaction 事務(wù)）
Data []byte
//4.創(chuàng)建時間的時間戳
TimeStamp int64
//5.當(dāng)前區(qū)塊的Hash值
Hash []byte
//6.Nonce 隨機(jī)數(shù)，用于驗(yàn)證工作量證明
Nonce int64
}
//1. 創(chuàng)建新的區(qū)塊
func NewBlock(data string, height int64, PreBlockHash []byte) *Block {
//創(chuàng)建區(qū)塊
block := &Block{
height,
PreBlockHash,
[]byte(data),
time.Now().Unix(),
nil,
0,
}
//調(diào)用工作量證明的方法，并且返回有效的Hash和Nonce值
//創(chuàng)建pow對象
pow := NewProofOfWork(block)
//挖礦驗(yàn)證
hash, nonce := pow.Run(height)
block.Hash = hash[:]
block.Nonce = nonce
return block
}
//2.生成創(chuàng)世區(qū)塊
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. 測試代碼，測試挖礦
main.go
package main
import (
"publicChain/part2-工作量證明/BLC"
"fmt"
)
func main() {
fmt.Println("開始挖礦")
//創(chuàng)建創(chuàng)世區(qū)塊
blockChain := BLC.CreateBlockChainWithGenesisBlock()
//創(chuàng)建新的區(qū)塊
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("創(chuàng)建的區(qū)塊鏈為:\t%v\n", blockChain)
fmt.Printf("區(qū)塊鏈存儲的區(qū)塊為:\t%v\n", blockChain.Blocks)
fmt.Printf("第二個區(qū)塊的數(shù)據(jù)信息(交易信息)為:\t%v\n", string(blockChain.Blocks[1].Data))
fmt.Printf("第二個區(qū)塊的隨機(jī)數(shù)為:\t%v\n", blockChain.Blocks[1].Nonce)
}測試結(jié)果
共計(jì)對五個區(qū)塊進(jìn)行挖礦，結(jié)果如上
5.驗(yàn)證區(qū)塊有效性
ProofOfWork.go
//判斷挖礦得到的區(qū)塊是否有效
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
}測試代碼:
main.go
//通過POW挖出新的區(qū)塊block
block := BLC.NewBlock("Send $500 to Tom", blockChain.Blocks[len(blockChain.Blocks)-1].Height+1, blockChain.Blocks[len(blockChain.Blocks)-1].Hash)
//手動將該區(qū)塊添加至區(qū)塊鏈中
blockChain.Blocks = append(blockChain.Blocks, block)
//創(chuàng)建一個工作量證明對象
proofOfWork := BLC.NewProofOfWork(block)
//判斷該區(qū)塊是否合法有效
fmt.Println(proofOfWork.IsValid())測試結(jié)果:
第六個區(qū)塊是我們新創(chuàng)建的區(qū)塊，返回值為true，驗(yàn)證有效
參考資料:
區(qū)塊鏈共識算法-POW: https://www.jianshu.com/p/b23cbafbbad2
