我要在 Node.js 中为 SHA 加密导入什么？

Question

我正在尝试从我在网上找到的网站重新创建一些代码。该代码应该在 Node.js 中创建一个区块链。但是，当我运行它时，它会识别命令：

return sha(JSON.stringify(this.data) + this.prevHash + this.index + this.timestamp);

它returns错误：

return sha(JSON.stringify(this.data) + this.prevHash + this.index + this.timestamp);
                ^

ReferenceError: sha is not defined
    at Block.getHash (C:\Users\winst\OneDrive\Documents\Blockchain\main.js:12:3)
    at new Block (C:\Users\winst\OneDrive\Documents\Blockchain\main.js:8:19)
    at BlockChain.addBlock (C:\Users\winst\OneDrive\Documents\Blockchain\main.js:22:14)
    at Object.<anonymous> (C:\Users\winst\OneDrive\Documents\Blockchain\main.js:42:9)
    at Module._compile (internal/modules/cjs/loader.js:702:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:713:10)
    at Module.load (internal/modules/cjs/loader.js:612:32)
    at tryModuleLoad (internal/modules/cjs/loader.js:551:12)
    at Function.Module._load (internal/modules/cjs/loader.js:543:3)
    at Function.Module.runMain (internal/modules/cjs/loader.js:744:10)

我应该导入什么才能定义 sha？完整代码：

class Block{

    constructor(index, data, prevHash){
    this.index = index;
    this.timestamp = Math.floor(Date.now() / 1000);
    this.data = data;
    this.prevHash = prevHash;
    this.hash = this.getHash();
    }

    getHash(){
        return sha(JSON.stringify(this.data) + this.prevHash + this.index + this.timestamp);
    }
}
class BlockChain{
    constructor(){
        this.chain = [];
    }
    addBlock(data){
    let index = this.chain.length;
    let prevHash = this.chain.length !== 0 ? this.chain[this.chain.length - 1].hash : 0;
    let block = new Block(index, data, prevHash);

    this.chain.push(block);
    }
    chainIsValid(){

    for(var i=0;i<this.chain.length;i++){

        if(this.chain[i].hash !== this.chain[i].getHash()) 
            return false;

        if(i > 0 && this.chain[i].prevHash !== this.chain[i-1].hash)
            return false;
    }

    return true;
}   
}
const CILCoin = new BlockChain();

CILCoin.addBlock({sender: "Bruce wayne", reciver: "Tony stark", amount: 100});
CILCoin.addBlock({sender: "Harrison wells", reciver: "Han solo", amount: 50});
CILCoin.addBlock({sender: "Tony stark", reciver: "Ned stark", amount: 75});

console.log(JSON.stringify(CILCoin, null, 4));

Link 我从以下网站找到的：https://codingislove.com/simple-blockchain-javascript/

Answer 1

您可能需要在此处创建自己的方法，因为 sha() 不是内置于节点中的函数。您需要访问作为节点一部分的 crypto 模块。

https://nodejs.org/api/crypto.html#crypto_crypto

你可以构建一个函数

const crypto = require('crypto');

const secret = 'abcdefg';
const hash = crypto.createHmac('sha256', secret)
                   .update('I love cupcakes')
                   .digest('hex');
console.log(hash);
// Prints:
//   c0fa1bc00531bd78ef38c628449c5102aeabd49b5dc3a2a516ea6ea959d6658e

Answer 2

~~我喜欢使用 sha256 package.~~ Never mind, this has been deprecated. I would instead opt for use of the sha.js 包。

var sha = require('sha.js');
//...
getHash() {
    return sha('sha256').update(JSON.stringify(this.data) + this.preHash + this.index + this.timestamp).digest('hex');
}

我要在 Node.js 中为 SHA 加密导入什么？

What do I import for SHA encryption in Node.js?

javascript

node.js

encryption

blockchain

sha