get blob_key from an existed file in cloudstorage

Question

In Google Appengine, is it possible to retrieve the blob_key from google cloud storage filepath? The file is upload to cloud storage directly.

The document only shows how to create a file in cloud storage and get the blob_key. https://developers.google.com/appengine/docs/python/blobstore/#Python_Using_the_Blobstore_API_with_Google_Cloud_Storage

Answer 1

It's possible you don't actually need such a key: if you uploaded the file directly, I assume you know the bucket name and object name/path? With this you can serve the object by constructing a URL (e.g. http://storage.googleapis.com/<bucket-name>/<object-path>) and you can read it using the Cloud Storage Client Library's open() function.

I've not used blob_keys myself, but the use case for them seems to be where an uploaded file needs to be served from a location which is unknown and therefore a GCS URL cannot be formed.