go语言写的案例
1.计算哈希，创建 区块
package coreimport ("crypto/sha256""encoding/hex""time"
)type Block struct {Index int64 // 区块编号Timestmp int64 // 区块时间戳PreBolckHash string // 上一个区块的哈希值Hash string // 当前区块哈希值Data string // 区块数据
}// 计算哈希
func CalculateHash(b Block) string {// 数据不允许修改// 把 数据 包含在hash运算的数值里面， ，任何一个模块数据的修改，都会导致区块链， 链式数据结构的破坏blockData := string(b.Index) + string(b.Timestmp) + string(b.PreBolckHash)HashInBytes := sha256.Sum256([]byte(blockData))return hex.EncodeToString(HashInBytes[:])
}// 生成新区块
func GenerateNewBlock(preBlock Block, data string) Block {newBlock := Block{}// 新区块的index = 父区块的index+1newBlock.Index = preBlock.Index + 1// 哈希值 = 父区块的哈希值newBlock.PreBolckHash = preBlock.Hash// 新区块的时间戳，==当前时间newBlock.Timestmp = time.Now().Unix()newBlock.Data = data// 新区块的哈希 是计算得来的newBlock.Hash = CalculateHash(newBlock)return newBlock
}// 生成创始区块
func GenerateGenesisBlock() Block {preBlock := Block{}preBlock.Index = -1preBlock.Timestmp = time.Now().Unix()preBlock.Hash = CalculateHash(preBlock)preBlock.Data = "Genesis Block(创始区块)"GenerateNewBlock(preBlock, "Genesis Block")return preBlock
}
链式数据
package coreimport ("fmt""log"
)type Blockchain struct {// 数组Blocks []*Block
}func NewBlockchain() *Blockchain {genesisBlock := GenerateGenesisBlock()blockchain := Blockchain{}blockchain.ApendBlock(&genesisBlock)return &blockchain
}func (bc *Blockchain) SendData(data string) {proBlock := bc.Blocks[len(bc.Blocks)-1]newBlock := GenerateNewBlock(*proBlock, data)bc.ApendBlock(&newBlock)
}func (bc *Blockchain) ApendBlock(newBlock *Block) {// 防止越界if len(bc.Blocks) == 0 {bc.Blocks = append(bc.Blocks, newBlock)return}if isValid(*newBlock, *bc.Blocks[len(bc.Blocks)-1]) {bc.Blocks = append(bc.Blocks, newBlock)} else {log.Fatal("invalid block")}
}func (bc *Blockchain) Print() {// 下划线表示赋值是忽略的for _, block := range bc.Blocks {fmt.Printf("Index: %d\n", block.Index)fmt.Printf("Prev.Hash: %s\n", block.PreBolckHash)fmt.Printf("Curr.Hash: %s\n", block.Hash)fmt.Printf("Data: %s\n", block.Data)fmt.Printf("Timestmp: %d\n", block.Timestmp)fmt.Println("")}
}func isValid(newBlock Block, oldBlock Block) bool {if newBlock.Index-1 != oldBlock.Index {return false}if newBlock.PreBolckHash != oldBlock.Hash {return false}if CalculateHash(newBlock) != newBlock.Hash {return false}return true
}
启动类
package mainimport "./core"func main() {bc := core.NewBlockchain()bc.SendData("Send 1 BTC to jacky")bc.SendData("Send 1 EOS to jacky")bc.Print()
}