Node.js hmac.update()方法
原文:https://www.geeksforgeeks.org/node-js-hmac-update-method/
HMAC.update() 方法是加密模块中 hmac 类的内置方法，用于更新 hmac 对象的数据。
语法:
hmac.update(data[, inputEncoding])
参数:该方法取以下两个参数:
- Data: It can be a string, Buffer, TypedArray or DataView type. What is passed to this function is data.
- Enter the code: is an optional parameter. It is the encoding of the data string.
返回值:此方法不返回任何内容。
项目设置:新建一个 NodeJS 项目并命名为 hmac 。
mkdir hmac && cd hmac
npm init -y
现在创建一个。js 文件，并将其命名为 index.js
例 1:
index . js
// Node.js program to demonstrate the
// crypto hmac.update() method
// Importing crypto module
const { createHmac } = require('crypto')
// Creating and initializing algorithm and password
const algo = 'sha256'
const secret = 'GFG Secret Key'
// Create an HMAC instance
const hmac = createHmac(algo, secret)
// Update the internal state of the hmac object
hmac.update('GeeksForGeeks')
// Perform the final operations
// Return calculated hash
const result = hmac.digest('base64')
// Print the result
console.log(`HMAC hash: ${result}`)
使用以下命令运行 index.js 文件:
node index.js
输出:
HMAC hash: yK4+CYVa56w0Ba1g2TdY7cDM68HPXFKb+10FhnRpXFM=
例 2:
index . js
// Node.js program to demonstrate the
// crypto hmac.update() method
// Defining myfile
const myfile = process.argv[2];
// Includes crypto and fs module
const crypto = require('crypto');
const fs = require('fs');
// Creating and initializing algorithm and password
const algo = 'sha256'
const secret = 'GFG Secret Key'
// Creating Hmac
const hmac = crypto.createHmac(algo, secret);
// Creating read stream
const readfile = fs.createReadStream(myfile);
readfile.on('readable', () => {
// Calling read method to read data
const data = readfile.read();
if (data)
// Updating
hmac.update(data);
else {
// Perform the final operations
// Return hash value
const result = hmac.digest('hex')
// Display result
console.log(`HMAC hash value of ${myfile}: ${result}`);
}
});
使用以下命令运行 index.js 文件:
node index.js package.json
输出:
包的 HMAC 哈希值. JSON:38f 0 f 975 f 8964343 c 24 da 940188 aeb 6 bb 20842 E3 C5 BF 03 CB 66773 e 98 beeb 73
参考:https://nodejs . org/API/crypto . html # crypto _ hmac _ update _ data _ input encoding
版权属于：月萌API www.moonapi.com，转载请注明出处
