체인블록 만들면서 알아보기.

import * as crypto from "crypto";

interface BlockShape{
    hash:string;
    prevHash:string;
    height:number;
    data:string;
}

class Block implements BlockShape {
    public hash:string;
    constructor(
        public prevHash:string,
        public height: number,
        public data: string
    ){
        console.log(`Creating block with height ${height}${data}`);
        this.hash = Block.calculateHashs(prevHash,height,data);
    }
    static calculateHashs(prevHash:string,height:number,data:string){
        const toHash = `${prevHash}${height}${data}`
        return crypto.createHash("sha256").update(toHash).digest("hex")
    }
}

class Blockchain {
    private blocks: Block[]
    constructor(){
        this.blocks = []
    }
    private getPrevHash(){
        if(this.blocks.length === 0){return ""}
        return this.blocks[this.blocks.length -1].hash
    }
    public addBlock(data:string){
        const newBlock = new Block(this.getPrevHash(), this.blocks.length + 1, data);
        this.blocks.push(newBlock)
    }
    public getBlocks(){
        return [...this.blocks];
    }
}

const blockchain = new Blockchain() ;
blockchain.addBlock("First one");
blockchain.addBlock("Second one");
blockchain.addBlock("Third one");

console.log(blockchain.getBlocks());

완성 코드이나 이해하는데 약간 어려운부분이 있다.

 

하이트값이 어디서 생성되는지 크립토 라는 라이브러리 사용하는데 무엇을 가져오는지도.

기본적으로 헤쉬값을 만드는데 크립토에서 값을 가져오는지 의문이듬.