[Owncloud] Syncing and Time Synchronization

[Evert Pot]

On Jul 18, 2012, at 4:19 PM, Klaas Freitag wrote:

> On 18.07.2012 15:40, Bart Visscher wrote:
> Hi,
> 
>>>> On Wed, Jul 18, 2012 at 10:31:13AM +0200, Klaas Freitag wrote:
>>>>> For that, the best would be if the ownCloud WebDAV server would
>>>>> provide another WebDAV property that returns the md5-sum of the file
>>>>> or file list. That probably means that the md5 sum needs to be
>>>>> calculated on every file change on the server and be stored in the
>>>>> fs cache.
>>>> 
>>>> I think you could use the etag for that, this is a standard property in
>>>> WebDAV.
>>> AFAIU Etags could help us here if the PUT of a new file to the
>>> server would have an ETag in the response which could be stored on
>>> the client. On subsequent sync runs, the Etag could be checked to
>>> see if it has changed. Yet, currently I can neither see an etag in
>>> the PUT response nor in a GET. That is probably because the getETag
>>> implementation in lib/connector/sabre/file.php returns null. So that
>>> would still have to be implemented.
>> 
>> Yes, but this shouldn't be that much work.
> Nice idea, but does not work ;-( . Currently the client gets file information directory wise, not by issuing an request for every file. Since etag work as HTTP header, that does not work here.
> 
> We instead have to implement it as Custom webdav property which the client can query via PROPFIND, and gets the MD5 sum for every file in return.

http://tools.ietf.org/html/rfc4918#section-15.6


Related to the sync discussion; don't ignore this rfc:

http://tools.ietf.org/html/rfc6578

It's easily superior to all the approaches discussed here in the last little while.

Evert