Node.js获取文件hash值

Node获取文件hash值 

let fs = require('fs');
let crypto = require('crypto');

// enum
const algorithmType = {
    SHA256:"SHA256",
    SHA1:"SHA1",
    MD5:"MD5"
}

/**
 * promise
 * @param filePath
 * @param algorithm
 * @returns {Promise}
 */
const hashFileSha256 = (filePath,algorithm)=>{
    return new Promise((resolve,reject)=>{
        if (!fs.existsSync(filePath)){
            reject("the file does not exist, make sure your file is correct!");
            return;
        }
        if (!algorithmType.hasOwnProperty(algorithm)){
            reject("nonsupport algorithm, make sure your algorithm is [SHA256,SHA1,MD5] !");
            return;
        }
        let stream = fs.createReadStream(filePath);
        let hash = crypto.createHash(algorithm.toLowerCase());

        stream.on('data',function (data) {
            hash.update(data)
        })

        stream.on('end',function () {
            let final = hash.digest('hex');
            resolve(final)
        })

        stream.on('error',function (err) {
            reject(err)
        })
    })
}

/**
 * async
 * @param filePath
 * @param algorithm
 * @returns {string|Error}
 */
const hashFileSha256Async = (filePath,algorithm)=>{
    if (!fs.existsSync(filePath)){
        return new Error("the file does not exist, make sure your file is correct!");
    }
    if (!algorithmType.hasOwnProperty(algorithm)){
        return new Error("nonsupport algorithm, make sure your algorithm is [SHA256,SHA1,MD5] !");
    }
    let buffer = fs.readFileSync(filePath);
    let hash = crypto.createHash(algorithm.toLowerCase());
    hash.update(buffer)
    let final = hash.digest('hex');
    return final;
}

exports.hashFileSha256 = hashFileSha256
exports.hashFileSha256Async = hashFileSha256Async
exports.algorithmType = algorithmType

调用示例：

const f = require('../incremental/hashFile')
const filePath = path.resolve(__dirname,'./binaryFile');

let hashVal = f.hashFileSha256Async(filePath,f.algorithmType.SHA256)
console.log(hashVal)