如何使用云函数为Firebase从云存储中获取对象？

Question

我很抱歉。我以前也提出过同样的问题，但被认为与这个答案重复。我真的不明白那里的答案，我也不明白为什么那个问题会回答我的问题。在我看来很不一样。我需要获取图像对象，但答案是创建一个流。有人能帮我把答案和我的问题联系起来吗？我是新的云功能。请

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如果我为Firebase云存储触发器使用云函数。我可以像这样获取图像对象

exports.compressImage = functions.region("asia-east2").storage.object().onFinalize(async (object) => {
    
   // I can get the `object` easily in here

})

但现在我想使用firestore触发器做一些事情，并且我想在firestore触发器中从我的bucket中获取一个对象

exports.dbEventsOnCreate = functions..firestore.document(path).onCreate(async (snapshot,context) => {

    // I want to get an image `object` with a specific path from firebase storage bucket in here

})

这是我的图像在firebase存储中的路径

那么如何在我的云函数firestore触发器中从路径中的bucket获取图像对象呢？

Answer 1

// Download file from bucket.
const bucket = admin.storage().bucket(fileBucket);
const tempFilePath = path.join(os.tmpdir(), fileName);
const metadata = {
  contentType: contentType,
};
await bucket.file(filePath).download({destination: tempFilePath});
console.log('Image downloaded locally to', tempFilePath);

await bucket.upload(tempFilePath, {
  destination: thumbFilePath,
  metadata: metadata,
});
// Once the thumbnail has been uploaded delete the local file to free up disk space.
return fs.unlinkSync(tempFilePath);