Short description
for attachments, wanted to use an online storage service instead of file system. Found it necessary to isolate parts of AttachFile.py that deal with underlying storage system. Once these parts are isolated into separate functions, it is easier to drop in alternate storage system by overriding the functions that directly touch the storage system.
patch:
Note: for moin2, this patch does not apply - moin2 does not have "attachments". But maybe some backend could be done to realize the idea behind the patch.