如何管理谷歌云存储(Node.js)中对象的权限？

const { Storage } = require('@google-cloud/storage');
const storage = new Storage();

const bucketName = 'your-bucket-name';
const fileName = 'your-file-name';
const file = storage.bucket(bucketName).file(fileName);

const userEmail = 'user@example.com';
file.acl.add({
  entity: `user-${userEmail}`,
  role: storage.acl.READER_ROLE
}, (err, aclObject) => {
  if (err) {
    console.error(err);
    return;
  }
  console.log(`Added read permission for ${userEmail}`);
});