signature.js

import crypto from 'crypto';

/**
 * @param {String} secret
 * @param {String} href
 * @param {Object} payload
 */
export default (secret, href, payload) => {
    payload = JSON.stringify(payload);
    calculated = crypto
        .createHmac('sha1', secret)
        .update(payload)
        .update(href)
        .digest('base64');
    return calculated;
};