Get Authentication header with OAuth using oauth-1.0a and crypto-js

oauth.js

import OAuth from 'oauth-1.0a';
import CryptoJS from 'crypto-js';

/**
 * oAuthHeader - Get Authentication header with OAuth.
 *
 * @param  {string} url    Request URL
 * @param  {string} method HTTP method.
 * @return {object}        Authentication header object
 */
function oAuthHeader(url, method, session, token) {
  
  if (!session || !token) {
    throw new Error('Traying to generate OAuth headers without valid access token or session.');
  }

  let oauthObject = new OAuth({
      consumer: {
          key: session,
          secret: token
      },
      signature_method: 'HMAC-SHA1',
      nonce_length: 6,
      version: '1.0',
      hash_function: function(base_string, key) {
        return CryptoJS.HmacSHA1(base_string, key).toString(CryptoJS.enc.Base64);
      }
  });

  return oauthObject.toHeader(oauthObject.authorize({url: url, method: method}));
}