code: function getCachedImageSizeFromUrl(url) {
      if (!url || url === undefined || url === null) {
          return;
      }
  
      // image size is not in cache
      if (!cache[url]) {
          return imageSize.getImageSizeFromUrl(url).then(function (res) {
              cache[url] = res;
  
              debug('Cached image:', url);
  
              return cache[url];
          }).catch(common.errors.NotFoundError, function () {
              debug('Cached image (not found):', url);
              // in case of error we just attach the url
              cache[url] = url;
  
              return cache[url];
          }).catch(function (err) {
              debug('Cached image (error):', url);
              common.logging.error(err);
  
              // in case of error we just attach the url
              cache[url] = url;
  
              return cache[url];
          });
      }
      debug('Read image from cache:', url);
      // returns image size from cache
      return cache[url];
  }
docs: Get cached image size from URL
  Always returns {object} imageSizeCache
  @param {string} url
  @returns {Promise<Object>} imageSizeCache
  @description Takes a url and returns image width and height from cache if available.
  If not in cache, `getImageSizeFromUrl` is called and returns the dimensions in a Promise.