I'm curious what cloud storage systems offer an append only mode, especially open source ones. In particular, would any cloud storage systems support the following workflow :
- Anonymous users may upload messages/files into identifiable locations which we'll call buckets.
- All users should have read access to all messages/files, but no anonymous user should have permissions to modify or delete them.
- Buckets have associated public keys which a moderator uses to authenticate approvals or deletions of uploads.
- Unapproved messages/files are eventually culled by the system to save space.
There was some discussion about adding append-only access to mutable files (append-caps) to Tahoe-LAFS, but afaik nobody has implemented this yet.