Add custom functions to a Google sheet to pull user info directly from Twitter REST API

twitterUserInfoFunctions.gs

// Based on a script by @laurenancona here:
// https://gist.github.com/laurenancona/1f3b8ce7a50e7d24ad04adccebce3fa3

// Which was based on script by @SarahMarshall here: 
// http://sarahmarshall.io/post/70812214349/how-to-add-twitter-follower-counts-to-a-google 

// For these keys, create an application at https://dev.twitter.com
var CONSUMER_KEY = 'INSERT CONSUMER KEY';
var CONSUMER_SECRET = 'INSERT CONSUMER SECRET';

var BASE_API_URL = "https://api.twitter.com/1.1/";


// Get follower count of user
function getTwitterUserFollowers(id) {
  var url = BASE_API_URL + "users/show.json?screen_name=" + id;
  return twitterRequest(url).followers_count;
}


// Get count of tweets by user
function getTwitterUserTweetCount(id) {
  var url = BASE_API_URL + "users/show.json?screen_name=" + id;
  return twitterRequest(url).statuses_count;
}


// Get verified status
function getTwitterUserVerified(id) {
  var url = BASE_API_URL + "users/show.json?screen_name=" + id;
  return twitterRequest(url).verified;
}


// Get user profile image
function getTwitterUserProfileImage(id) {
  var url = BASE_API_URL + "users/show.json?screen_name=" + id;
  return twitterRequest(url).profile_image_url_https;
}


// private function to request stuff from twitter
var twitterRequest = function(url) {
  // Encode consumer key and secret
   var tokenUrl = "https://api.twitter.com/oauth2/token";
   var tokenCredential = Utilities.base64EncodeWebSafe(
     CONSUMER_KEY + ":" + CONSUMER_SECRET);

   //  Obtain a bearer token with HTTP POST request
   var tokenOptions = {
     headers : {
       Authorization: "Basic " + tokenCredential,
       "Content-Type": "application/x-www-form-urlencoded;charset=UTF-8" 
     },
     method: "post",
     payload: "grant_type=client_credentials"
   };

   var responseToken = UrlFetchApp.fetch(tokenUrl, tokenOptions);
   var parsedToken = JSON.parse(responseToken);
   var token = parsedToken.access_token;

   // Authenticate Twitter API requests with the bearer token
   var apiOptions = {
     headers : {
       Authorization: 'Bearer ' + token
     },
     "method" : "get"
   };

   var responseApi = UrlFetchApp.fetch(url, apiOptions);

   if (responseApi.getResponseCode() == 200) {

     // Parse the JSON encoded Twitter API response
     var response = JSON.parse(responseApi.getContentText());
     return response;
   }
}