ブロックチェーンの開発と実装に Go 言語を使用する方法

type Block struct {
    Index     int
    Timestamp string
    Data      []byte
    PrevHash  []byte
    Hash      []byte
}

type Blockchain struct {
    Blocks []*Block
}

func InitBlockchain() *Blockchain {
    return &Blockchain{[]*Block{createGenesisBlock()}}
}

func createGenesisBlock() *Block {
    return &Block{0, "01/01/1970", []byte("Genesis Block"), []byte{}, []byte{}}
}

func (bc *Blockchain) AddBlock(data []byte) {
    prevBlock := bc.Blocks[len(bc.Blocks)-1]
    newBlock := generateBlock(prevBlock, data)
    bc.Blocks = append(bc.Blocks, newBlock)
}

func generateBlock(prevBlock *Block, data []byte) *Block {
    newBlock := &Block{}
    newBlock.Index = prevBlock.Index + 1
    newBlock.Timestamp = time.Now().String()
    newBlock.Data = data
    newBlock.PrevHash = prevBlock.Hash
    newBlock.Hash = generateHash(newBlock)
    return newBlock
}

func generateHash(block *Block) []byte {
    record := strconv.Itoa(block.Index) + block.Timestamp + string(block.Data) + string(block.PrevHash)
    h := sha256.New()
    h.Write([]byte(record))
    hash := h.Sum(nil)
    return hash
}

func main() {
    blockchain := InitBlockchain()
    blockchain.AddBlock([]byte("This is the first block"))
    blockchain.AddBlock([]byte("This is the second block"))
    
    for _, block := range blockchain.Blocks {
        fmt.Println("Index:", block.Index)
        fmt.Println("Timestamp:", block.Timestamp)
        fmt.Println("Data:", string(block.Data))
        fmt.Println("PrevHash:", block.PrevHash)
        fmt.Println("Hash:", block.Hash)
        fmt.Println()
    }
}