There are few open source options that offer a file API: - https://remotestorage.io/ - https://docs.nextcloud.com/server/14/developer_manual/client_apis/WebDAV/index.html Please note in some way also https://solid.mit.edu/ fits into this scheme.
There are few open source options that offer a file API:
Please note in some way also https://solid.mit.edu/ fits into this scheme.