fatsecret web API request

const crypto = require('crypto');
const queryString = require('query-string');
const urlencode = require('urlencode');
const rp = require('request-promise');

const method = 'GET';
const url = 'http://platform.fatsecret.com/rest/server.api';
const params = {
  method: 'foods.search',
  format: 'json',
  search_expression: req.query.search,
  oauth_signature_method: 'HMAC-SHA1',
  oauth_consumer_key: process.env.FATSECRET_CLIENT_KEY,
  oauth_nonce: (new Date()).getTime().toString(32),
  oauth_timestamp: (new Date()).getTime(),
  oauth_version: '1.0'
};

const base = `${method}&${urlencode(url)}&${urlencode(queryString.stringify(params))}`;
const key = `${process.env.FATSECRET_CLIENT_SECRET}&`;

const hash = crypto.createHmac('sha1', key).update(base).digest('base64');

Object.assign(params, { oauth_signature: hash });

rp({
  method,
  url,
  qs: params,
  json: true
})
  .then(response => console.log(response));