- From: Michael Nordman <michaeln@google.com>
- Date: Wed, 26 Aug 2009 17:05:20 -0700
> Maybe the local storage API needs a way to distinguish between cached data that can be silently thrown away, and important data that can't.* * *What if instead of the storage APIs providing a way to distinguish things, UA's provide a way for users to indicate which applications are "important", and UA's provide a way for applications guide a user towards making that indication.* *Seems like permissioning, blessing, could happen out-of-band of the existing storage APIs.* * * On Wed, Aug 26, 2009 at 4:51 PM, Jens Alfke <snej at google.com> wrote: > > On Aug 26, 2009, at 4:01 PM, Linus Upson wrote: > > The analogy was made comparing a user agent that purges local storage to an > OS throwing out files without explicit user action. This is misleading since > most files arrive on your computer's disk via explicit user action. You copy > files to your disk by downloading them from the internet, copying from a > network drive, from a floppy, your camera, etc. > > > A web app would also be pretty likely to put stuff in local storage as a > result of explicit user action. The use cases seem pretty similar. > > Also, you're not counting files that you *create* locally. After all, > files have to come from somewhere :) Those are the most precious since > they're yours and they may not live anywhere else if you haven't backed them > up or copied them elsewhere. There's no reason web-apps can't create the > same kind of content, and it would look very similar to a user: I go to the > word processor [website], click New Document, type some stuff, and click > Save. > > Even if the save process involves migrating the local data up to the cloud, > that transition is not instantaneous: it can take arbitrarily large amounts > of time if there are network/server problems or the user is offline. During > that time, *the local storage represents the only copy of the data*. There > is therefore a serious race condition where, if the browser decides to purge > local data before the app has uploaded it, the data is gone forever. > > A better analogy would be, "What if watching TV caused 0-5MB size files to > silently be created from time to time in a hidden folder on your computer, > and when your disk filled up both your TV and computer stopped working?" > > > This is a cache ? that isn't the kind of usage I'm concerned about. Maybe > the local storage API needs a way to distinguish between cached data that > can be silently thrown away, and important data that can't. (For example, > the Mac OS has separate 'Caches' and 'Application Support' subfolders of > ~/Library/.) > > First, this is what quotas are for. The TV web-app would have a limited > quota of space to cache stuff. > Second, the browser should definitely help you delete stuff like this if > disk space does get low; I'm just saying it shouldn't delete it silently or > as part of some misleading command like "Empty Cache" or "Delete Cookies". > > At a minimum the HTML 5 spec should be silent on how user agents implement > local storage policies. I would prefer the spec to make it clear that local > storage is a cache, domains can use up to 5MB of space without interrupting > the user, and that UAs were free to implement varying cache eviction > algorithms. > > > That will have the effect of making an interesting category of new > applications fail, with user data loss, on some browsers. That sounds like a > really bad idea to me. > > To repeat what I said up above: *Maybe the local storage API needs a way > to distinguish between cached data that can be silently thrown away, and > important data that can't.* > > ?Jens > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.whatwg.org/pipermail/whatwg-whatwg.org/attachments/20090826/b0459b7e/attachment-0001.htm>
Received on Wednesday, 26 August 2009 17:05:20 UTC