@cybersource/flex-sdk-node/lib/cgk/signature.js

Easily create keys for use in a Flex API integration and verifying Flex token contents

/* Copyright (c) 2018 by CyberSource */

const crypto = require('crypto');

function generateSignature(headers, keyId, sharedSecret) {
  const headerKeys = Object.keys(headers);
  const signatureString = headerKeys.map(key => `${key}: ${headers[key]}`).join('\n');

  const signature = crypto.createHmac('sha256', Buffer.from(sharedSecret, 'base64'))
    .update(signatureString)
    .digest('base64');

  return [
    `keyid="${keyId}"`,
    'algorithm="HmacSHA256"',
    `headers="${headerKeys.join(' ')}"`,
    `signature="${signature}"`,
  ].join(', ');
}

module.exports = generateSignature;