Re: [Storagesync] Storagesync Digest, Vol 5, Issue 1

[Linhui Sun <[e-mail]>]

On 周一, 12月 7, 2015 at 08:20, Markus Unterwaditzer <[e-mail]>
wrote:
You need to store the etags from the last sync to see which ones have changed. The server only need to know the latest version in my view. They don't need to
be able to identify last sync or change, just to check whether metadata file is
latest is enough.
I'm doing this in vdirsyncer (https://github.com/untitaker/vdirsyncer), a
remoteStorage and CalDAV/CardDAV sync client and probably should do a
high-level blogpost about it.

On Mon, Dec 07, 2015 at 08:17:26AM +0800, Linhui Sun wrote:
> On 周一, 12月 7, 2015 at 01:36, Markus Unterwaditzer <[e-mail]>
> wrote:
> > IMO, etag is designed for client side cache. A typical usage: if the file
> > on the server has no actual change, the client will use the cache and the
> > server does not need to send the file content again. While for a storage
> > service, we also need some some similar mechanism at server side. In this
> > way, the client do not need to upload unchanged content to the server.
>
> There is no "true-and-only" usecase for etags, and no, you do not need
anything
> more than etags for synchronization. Using a additional "metadata" file, the
> client can cheaply determine whether local content changed and whether server
> content changed, and that's all that is required for (in this case) file
> synchronization. Sync conflicts are a different story, and the solution to
that
> heavily depends on the kind of data you're syncing. I'm a little bit confused
here: if I have a metadata file, why do I still need
> the etag? The metadata file should contain something equivalent to the etag.
>
> >
> > > --
> > > Sent from my phone. Please excuse my brevity.
> > >
> > > _______________________________________________
> > > Storagesync mailing list
> > > [e-mail]
> > > https://www.ietf.org/mailman/listinfo/storagesync
> > >
>
> > _______________________________________________
> > Storagesync mailing list
> > [e-mail]
> > https://www.ietf.org/mailman/listinfo/storagesync

> _______________________________________________
> Storagesync mailing list
> [e-mail]
> https://www.ietf.org/mailman/listinfo/storagesync