code: function extractRemoteAddressFromRequest(req) {
  
    if (typeof req.header('x-forwarded-for') !== 'undefined') {
  
      return req.header('x-forwarded-for');
    } else if (isObject(req.connection)) {
  
      return req.connection.remoteAddress;
    }
  
    return '';
  }
docs: This function checks for the presence of an `x-forwarded-for` header on the
  request to check for remote address forwards, if that is header is not
  present in the request then the function will attempt to extract the remote
  address from the express request object.
  @function extractRemoteAddressFromRequest
  @param {Object} req - the express request object
  @returns {String} - the remote address or, if one cannot be found, an empty
  string