code: function (callback) {
          // Name the destination folder
          context.tempName = generateId();
          // Create destination folder
          if (imageSizes.length) {
            context.tempFolder = tempPath + '/' + context.tempName;
            return fs.mkdir(context.tempFolder, callback);
          } else {
            return callback(null);
          }
        }
docs: make a temporary folder for our work