golang-Blockchain Learning 01

Objective

Blockchain technology is now also the IT sector of the network red, do a bit of technical learning, do not engage in a block chain with all the nerve to go out and greet others. Now learning the go language is just as hot as a wave of blockchain.

Profile

Golang Knowledge Points:
1. Use of Golang structural body
2, common API use, such as bytes. Join, sha256.sum256, StrConv. Formatint and so on, learn the application of arrays and slices
Blockchain Simplification Instructions:
1. The simplified block object block contains four members, TimeStamp (timestamp), Preblockhash (hash value of the previous chunk), data (stored content), hash (hash value of its own chunk)
2. A simplified Blockchain object containing an array of chunks to blocks

Construction of coded analog block chain creation

1, create a Golang project, the directory structure is as follows: directory structure

Description
The bin directory holds the executable file that compiles the build
Src-coin Storage Main.go
Src-core Storage Block.go and Blockchian.go

2, Block.go

package coreimport (    "time"    "strconv"    "bytes"    "crypto/sha256")type Block struct {    TimeStamp     int64//时间戳    Data          []byte//存储的数据信息    PrevBlockHash []byte// 上一个区块的hash    Hash          []byte//本区块的hash}// 创建一个新的区块func NewBlock(data string, prevBlockHash []byte) *Block {        // 新建一个区块，自己hash值为空    block := &Block{time.Now().Unix(), []byte(data), prevBlockHash, []byte{}}      // 计算自己区块的hash值    block.SetHash()    return block}func (b *Block) SetHash() {    strTimeStamp := []byte(strconv.FormatInt(b.TimeStamp, 10))    headers := bytes.Join([][]byte{b.PrevBlockHash, b.Data, strTimeStamp}, []byte{})    hash := sha256.Sum256(headers)    b.Hash = hash[:]}// 模拟创世区块func NewGenesisBlock() *Block {    return NewBlock("Genesis Block", []byte{})}

3, Blockchain.go

package coretype BlockChain struct {    Blocks []*Block}// 添加区块到链上func (bc *BlockChain) AddBlock(data string) {    preBlock := bc.Blocks[len(bc.Blocks)-1]// 获取前一个区块    newBlock := NewBlock(data, preBlock.Hash)//创建新区块    bc.Blocks = append(bc.Blocks, newBlock)// 链接新区块到链上}// 创建区块链func NewBlockChain() *BlockChain {    return &BlockChain{[]*Block{NewGenesisBlock()}}}

4. Main.go Test

package mainimport (    "core"    "fmt")func main() {    bc := core.NewBlockChain()//创建区块链    bc.AddBlock("send 1 btc to Ivan")// 添加一个区块到连上    bc.AddBlock("send 2 btc to Ivan")// 测试打印区块链上的信息    for _, block := range bc.Blocks {        fmt.Printf("PrevBlockHash:%x\n", block.PrevBlockHash)        fmt.Printf("Data:%s\n", block.Data)        fmt.Printf("Hash:%x\n", block.Hash)        fmt.Printf("TimeStamp:%d\n", block.TimeStamp)        println()    }}