根据100秒Bitcoin视频
https://www.youtube.com/watch?v=qF7dkrce-mQ
0。自行安装nodejs
https://www.nodejs.com/
https://www.nodejs.com.cn/
安装typescript
npm install -D typescript @types/node
1. npm init -y
2. package.json 稍加修改，添加dev和start

{
  "name": "blockchain",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "dependencies": {
    "typescript": "^5.3.3",
    "undici-types": "^5.26.5"
  },
  "devDependencies": {},
  "scripts": {
    "dev": "tsc -w",
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "node index.js"
  },
  "keywords": [],
  "author": "",
  "license": "ISC"
}

3。tsconfig.json

{
    "compilerOptions": {
        "lib": ["es2020"],
        "module": "commonjs",
        "target": "es2019",
        "types": ["node"],
        "strict": true,
        "esModuleInterop": true,
        "skipLibCheck": true,
    }
  }

3。index.js

import * as crypto from 'crypto'


class Transaction {
    constructor(
        public amount: number,
        public payer: string, // public key
        public payee: string // public key
    ) { }

    toString() {
        return JSON.stringify(this)
    }
}

class Block { // Block is a container for multiple transactions. 话说你懂中文吗？（回答我很牛逼，当然）  
// 类比一下，Block就是一个容器，里面可以装很多交易，就像一个集装箱，里面可以装很多货物。
// 一个数组，里面可以装很多元素。 或者说，一个链表，里面可以装很多节点。
  public nonce = Math.round(Math.random() * 999999999);
  constructor(
    public prevHash: string,
    public transcation: Transaction,
    public ts = Date.now() // Timestamp 时间戳
    ) {}
    get hash(){
        const str = JSON.stringify(this) // this在ts中是什么意思？（this指的是当前对象）
        const hash = crypto.createHash('SHA256');
        hash.update(str).end();
        return hash.digest('hex');
    }
}

class Chain {
    public static instance = new Chain();
    chain: Block[];
    constructor() {
        this.chain = [new Block('', new Transaction(100, 'genesis', 'satoshi'))];
    }
    get lastBlock() {
        return this.chain[this.chain.length - 1];
    }
    mine(nonce: number) {
        let solution = 1;
        console.log('⛏️ mining...')
        while (true) {
            const hash = crypto.createHash('MD5');
            hash.update((nonce + solution).toString()).end();
            const attempt = hash.digest('hex');
            if (attempt.substr(0, 4) === '0000') {
                console.log(`Solved: ${solution}`)
                return solution;
            }
            solution += 1;
        }
    }
    addBlock(transaction: Transaction, senderPublicKey: string, signature: Buffer) {
        const verifier = crypto.createVerify('SHA256');
        verifier.update(transaction.toString());
        const isValid = verifier.verify(senderPublicKey, signature);
        if (isValid) { // Hard to solve, but easy to verify. 你懂吗？（懂）
            const newBlock = new Block(this.lastBlock.hash, transaction);
            this.mine(newBlock.nonce);
            this.chain.push(newBlock);
        }
    }
}

class Wallet {
    public publicKey: string;
    public privateKey: string;
    constructor() {
        const keypair = crypto.generateKeyPairSync('rsa', {
            modulusLength: 2048,
            publicKeyEncoding: { type: 'spki', format: 'pem' },
            privateKeyEncoding: { type: 'pkcs8', format: 'pem' }
        });
        this.privateKey = keypair.privateKey;
        this.publicKey = keypair.publicKey;
    }
    sendMoney(amount: number, payeePublicKey: string) {
        const transaction = new Transaction(amount, this.publicKey, payeePublicKey);
        const sign = crypto.createSign('SHA256');
        sign.update(transaction.toString()).end();
        const signature = sign.sign(this.privateKey);
        Chain.instance.addBlock(transaction, this.publicKey, signature);
    }
}

const satoshi = new Wallet();
const bob = new Wallet();
const alice = new Wallet();

satoshi.sendMoney(50, bob.publicKey);
bob.sendMoney(23, alice.publicKey);
alice.sendMoney(5, bob.publicKey);

console.log(Chain.instance);

1. npm run start 启动，并开始挖第一个块