[whatwg] Cross-domain databases; was: "File package protocol and manifest support?"

[Brett Zamir]

I would like to suggest an incremental though I believe significant 
enhancement to Offline applications/SQLite.

That is, the ability to share a complete database among offline 
applications according to the URL from which it was made available. It 
could be designated by the origin site as a read-only database, or also 
potentially with shared write access, shareable with specific domains or 
all domains, and perhaps also with a mechanism to indicate the license 
of its contents.  Perhaps the manifest file could include such 
information. Actually, there might even be a shared space for databases 
directly downloaded by the user (or by an application) which would allow 
all applications access, no doubt requiring UA permission.

Ideally the origin site could also have control over providing an update 
to the database (not necessarily through manually performing UPDATE 
commands, but potentially by simply providing a new database at the 
previous location which was checked periodically for a new modification 
date). I don't know whether it would ideal to tie this in to the caching 
API (perhaps deleting the database reference could also cause it to be 
re-downloaded and also force the database to be re-created). Perhaps the 
cache API could also be optionally shared with other domains as well, 
allowing them to ensure their application was working with the latest data.

I believe custom protocols will also play into this well, as there could 
be a number of uses for operating on the same data set while linking to 
it in a way which is application-independent.

(Thanks to Kristof Zelechovski for helping me distill the essence of the 
idea a bit more succinctly and more in line with HTML 5's progress to date.)

Brett