云函数中的存储触发器将永远循环

Question

我有这个函数，可以从谷歌存储桶中检索上传的图像，然后生成图像的缩略图。该功能运行良好，但不会停止运行。 这是函数

const thumbarray = []
exports.generateTHUMBPIC = 
functions.storage.object('productpics/{pushId}').onFinalize((object, context) => {
// [START eventAttributes]
const fileBucket = object.bucket; // The Storage bucket that contains the file.
const filePath = object.name; // File path in the bucket.
const contentType = object.contentType; // File content type.
const resourceState = object.resourceState; // The resourceState is 'exists' or 'not_exists' (for file/folder deletions).
const metageneration = object.metageneration; // Number of times metadata has been generated. New objects have a value of 1.
const fileDir1 = path.dirname(filePath);
const fileName0 = path.basename(filePath);
const fileDir = fileDir1.replace('productpics/', '')
console.log("file directory ***********",fileDir)
console.log("This is the object ",object)
console.log("This is the object ",context)
var listingid = fileDir.split("*")[1];
var userid = fileDir.split("*")[0];
var productid = fileDir.split("*")[2];
var thumbname = fileDir.split("*")[3]; // thumbnail 1 or 2 or 3
thumbarray.push(thumbname);
console.log("product id  ^^^^^^^^^^^^^^^",productid)
console.log("This is the file path ",filePath)
console.log('This is the created path',"productpics/ "+ context.params.pushId +" /productimg" );

const thumbFilePath = path.normalize(path.join(fileDir1, `${THUMB_PREFIX}${productid}`));
const tempLocalFile = path.join(os.tmpdir(), filePath);
const tempLocalDir = path.dirname(tempLocalFile);
const tempLocalThumbFile = path.join(os.tmpdir(), thumbFilePath);
const thumbnail_bucket = "thumbnails/"+fileDir;

console.log('This is the thumb nail bucket ', thumbnail_bucket);
// [END eventAttributes]
// [START stopConditions]
// Exit if this is triggered on a file that is not an image.
if (!contentType.startsWith('image/')) {
console.log('This is not an image.');
return null;
}

// Exit if the image is already a thumbnail.
if (productid.startsWith(THUMB_PREFIX)) {
console.log('Already a Thumbnail.');
return null;
}
// Download file from bucket.
const bucket = gcs.bucket(fileBucket);
const file = bucket.file(filePath);
const thumbFile = bucket.file(thumbFilePath);
const metadata = {
contentType: contentType,
};
// Create the temp directory where the storage file will be downloaded.
return mkdirp(tempLocalDir).then(() => {
console.log("This is the tempLocalfile ", tempLocalFile)
// Download file from bucket.
return file.download({
destination: tempLocalFile
});
}).then(() => {
// Generate a thumbnail using ImageMagick.
return spawn('convert', [tempLocalFile, '-thumbnail', `${THUMB_MAX_WIDTH}x${THUMB_MAX_HEIGHT}>`, tempLocalThumbFile], {
capture: ['stdout', 'stderr']
});
}).then(() => {
console.log('Thumbnail created at', tempLocalThumbFile);
// Uploading the Thumbnail.
console.log("thumb file use to be saved in ",thumbFilePath)
return bucket.upload(tempLocalThumbFile, {
destination: thumbnail_bucket,
metadata: metadata
});
})
.then(() => {
console.log('Thumbnail uploaded to Storage at', thumbnail_bucket);
// Once the image has been uploaded delete the local files to free up disk space.
fs.unlinkSync(tempLocalFile);
// fs.unlinkSync(tempLocalThumbFile);
// Get the Signed URLs for the thumbnail and original image.
const config = {
action: 'read',
expires: '03-01-2500',
};
return Promise.all([
thumbFile.getSignedUrl(config),
file.getSignedUrl(config),
]);
}).then((results) => {
// console.log('Got Signed URLs.');
// var thumbname = fileName0.split("*")[2];
const thumbResult = results[0];
const originalResult = results[1];
const thumbFileUrl = thumbResult[0];
const fileUrl = originalResult[0];
var updates = {};

updates['Listings/' + listingid + "/" + thumbname + "thumb"] = thumbFileUrl;
// updates['Listings/' + fileName +'/'+ thumbname] = thumbFileUrl;
return admin.database().ref().update(updates);

}).then(() => console.log('Thumbnail URLs saved to database.'));
})

我无法弄清楚我做错了什么。它似乎正在触发自己。我该如何解决这个问题？

Answer 1

如果您在 Cloud Storage触发器期间将文件上传到 Cloud Storage，则您的函数每次上传都会获得一次。

如果要防止这种情况，则需要一种方法来提前终止函数，方法是检查更改的文件是否是要处理的文件，然后返回函数而不进行任何处理。

例如，看看一些官方样本。