287-BitCoin全攻略三_创建区块链

BitCoin全攻略三







单个区块的代码已经差不多了
现在我们要创建多个区块
然后把一个个区块串联起来
形成 区块链




我们先来写一个结构体,表示区块链
然后里面就放的是区块数组
type BlockChain struct{
	blocks []*Block
}



然后我们写一个方法去创建区块链
func NewBlockChain() *BlockChain{
	bc := BlockChain{
		blocks: []*Block{},
	}
}



一般我们会在创建整个区块链的时候
同时去创建第一个区块
也就是 创世区块

genesisInfo := []byte("Hello world! Hello blockchain!")
genesisBlock := NewBlock(genesisInfo, []byte{})


然后我们把创世区块加入到区块链中

func NewBlockChain() *BlockChain{
	
	genesisInfo := []byte("Hello world! Hello blockchain!")
	genesisBlock := NewBlock(genesisInfo, []byte{})

	bc := BlockChain{
		blocks: []*Block{genesisBlock},
	}

	return &bc
}







然后我们来看看完整代码



package main

import (
	"crypto/sha256"
	"fmt"
)

type Block struct {
	//1.前区块哈希值
	PrevBlockHash []byte

	//2.当前区块的哈希
	Hash []byte

	//3.数据
	Data []byte
}

type BlockChain struct {
	Blocks []*Block
}

func main() {

	blocks := NewBlockChain().Blocks

	for i, block := range blocks {
		fmt.Println("========== 当前区块 ", i, "==========")
		fmt.Printf("前一区块的hash值为: %x\n", block.PrevBlockHash)
		fmt.Printf("当前区块的hash值为: %x\n", block.Hash)
		fmt.Printf("当前区块的data为: %s\n", block.Data)
	}

}

func NewBlockChain() *BlockChain {

	genesisInfo := []byte("Hello world! Hello blockchain!")
	genesisBlock := NewBlock(genesisInfo, []byte{})

	bc := BlockChain{
		Blocks: []*Block{genesisBlock},
	}

	return &bc
}

func NewBlock(data []byte, prevBlockHash []byte) *Block {

	block := Block{
		PrevBlockHash: prevBlockHash,
		Hash:          nil,
		Data:          data,
	}

	hash := getHash(&block)
	block.Hash = hash

	return &block
}

func getHash(block *Block) []byte {
	var info []byte
	info = append(info, block.PrevBlockHash...)
	info = append(info, block.Data...)
	hash := sha256.Sum256(info)
	return hash[:]
}