code: function uploadList(files) {
    return Promise.all(
      files.map(file =>
        upload(file)
          .then(({ uploadPath, output }) => {
            console.log(`Successfully uploaded: ${uploadPath}`) // eslint-disable-line no-console
            return output
          })
          .catch(err => {
            console.log('Error uploading:', err.message || err) // eslint-disable-line no-console
            return Promise.reject(err)
          })
      )
    )
  }
docs: Upload list of files or folders to Google Cloud Storage
  @param  {Array} files - List of files/folders to upload
  @return {Promise} Resolves with an array of upload results
  @private