const crypto = require('crypto'); const channelSecret = 'xxxxxxx' // envとかから取る exports.handler = async(event) => { const body = Buffer.from(event.body, 'base64').toString() const signature = crypto.createHmac('SHA256', channelSecret).update(body).digest('base64'); const isSignatureMatched = signature === event.headers['X-Line-Signature']; console.log('signature matched:', isSignatureMatched); // LINEからのリクエストならtrueになる }