We do have Cloud Run Functions that trigger on Cloud Storage events, as well as Cloud Pub/Sub notifications for the same. Is there a specific bit of functionality you're looking for?
Hi, Brandon from GCS here. If you're looking for all of the guarantees of a real, POSIX filesystem, you want to do fast top level directory listing for 100MM+ nested files, and POSIX permissions/owner/group and other file metadata are important to you, Gcsfuse is probably not what you're after. You might want something more like Filestore: https://cloud.google.com/filestore
Gcsfuse is a great way to mount Cloud Storage buckets and view them like they're in a filesystem. It scales quite well for all sorts of uses. However, Cloud Storage itself is a flat namespace with no built-in directory support. Listing the few top level directories of a bucket with 100MM files more or less requires scanning over your entire list of objects, which means it's not going to be very fast. Listing objects in a leaf directory will be much faster, though.
You can compose a 4TB object with a 1 byte object, or you can compose 32 150GB objects, just so long as the destination object doesn't go over 5 terabytes.
Hi, GCS engineer here. The lower limit on composing objects is one source object, in which case you are not so much composing as you are copying with style. Zero source objects is an error. I will file a note about the docs, thanks.