There are two ways to post tweets that contain images. You can either upload the picture(s) to an image hosting service and then paste the image URL into the tweet. The other option is that you natively upload the image into Twitter.

Here’s a sample snippet that shows how you can use Google Apps Script to upload and post images to Twitter with the new Twitter API. You can either pull an image from the web or you can use the DriveApp service to pull an image from your Google Drive.

To get started, you need to create a new Twitter app and generate the Consumer API keys. You’ll also need to include the Twitter Library in your Apps Script project (key MKvHYYdYA4G5JJHj7hxIcoh8V4oX7X1M_)

function sendTweetwithImage() {
  var twitterKeys = {
    TWITTER_CONSUMER_KEY: 'aa',
    TWITTER_CONSUMER_SECRET: 'bb',
    TWITTER_ACCESS_TOKEN: 'cc',
    TWITTER_ACCESS_SECRET: 'cc',
  };

  var props = PropertiesService.getUserProperties();

  props.setProperties(twitterKeys);

  var twit = new Twitter.OAuth(props);

  if (twit.hasAccess()) {
    try {
      // DriveApp.getFileById(id).getBlob()

      var imageUrl = 'http://img.labnol.org/di/M1.jpg';
      var imageBlob = twit.grabImage(imageUrl, 'image/jpeg');
      var uploadImg = twit.uploadMedia(imageBlob);

      if (uploadImg) {
        var status = 'Hello @labnol';

        var response = twit.sendTweet(status, {
          media_ids: uploadImg.media_id_string,
        });

        if (response) {
          Logger.log('Tweet Sent ' + response.id_str);
        } else {
          // Tweet could not be sent
          // Go to View -> Logs to see the error message
        }
      }
    } catch (f) {
      Logger.log(f.toString());
    }
  }
}