有没有人可以帮助验证Sendgrid在node中签名的webhook，因为文档中唯一的示例是Golang？

const crypto = require('crypto');
const express = require('express');
const app = express();

app.post('/sendgrid-webhook', (req, res) => {
  // 在这里进行签名验证的逻辑
});

const signature = req.headers['x-twilio-email-event-webhook-signature'];
const timestamp = req.headers['x-twilio-email-event-webhook-timestamp'];

let body = '';
req.on('data', (chunk) => {
  body += chunk;
});
req.on('end', () => {
  // 在这里进行签名验证的逻辑
});

const secret = 'YOUR_SENDGRID_SECRET'; // 替换为你的Sendgrid密钥
const hmac = crypto.createHmac('sha256', secret);
hmac.update(timestamp + body);
const calculatedSignature = hmac.digest('base64');

if (signature === calculatedSignature) {
  // 签名验证通过
  console.log('Webhook signature is valid.');
} else {
  // 签名验证失败
  console.log('Webhook signature is invalid.');
}