On Tue, May 4, 2010 at 2:08 PM, James Snell <[email protected]> wrote:
> I've noticed that Google has actually started using an etag attribute
> in their API which has roughly the same concerns about binding, etc.
> I'm a big fan of including as much metadata as practical possible
> without going overboard and think that a hash attribute (or set of
> hash attribute options not limited to md5) would be a good thing in
> general. I've been starting to dust off a few of the old I-D's this
> week starting with the tombstones draft (again) so perhaps I'll also
> pull out that link extensions draft and give it a do-over.
>

Very much appreciated.  Glad to see you back on atom-syntax.

--peter

> - James
>
> On Tue, May 4, 2010 at 11:57 AM, Peter Keane <[email protected]> wrote:
>>
>> On Tue, May 4, 2010 at 12:54 PM, Bob Wyman <[email protected]> wrote:
>>> I find that I have a real need for the "md5" Link rel mechanism defined in
>>> James Snell's old Atom Link Extensions draft or something functionally
>>> equivalent. Basically, what I need to do is ensure that the "src" attribute
>>> on an atom.content element is pointing to a known version of a resource
>>> rather than simply to any resource that has the same URL as in the src
>>> attribute. I'm then going to sign the Atom entry that contains this "by ref"
>>> content element.
>>
>> There have been a number of discussion of such in the past on
>> atom-syntax -- usually focussed on James Snell's link extension draft.
>>  You might also look at the Atom-Media extensions that came out of
>> activity streams work [1] -- no md5, but that'd be an obvious
>> addition.  I think the MediaRSS spec is widely used, and it does have
>> an md5 as a <media:hash> element w/ @algorithm [2].  When I have had
>> need for it, I generally used a locally name-spaced attribute on
>> atom:link, although that's obviously a sub-optimal solution.
>>
>> The RESTful implications of such a use are (I think) somewhat
>> interesting.  It creates a tight-binding (early binding) that is
>> somewhat at odds w/ the late-binding nature of REST.  I think that's
>> why attributes on atom:link are always "advisory" and overridable (see
>> RFC4287 sec. 4.2.7.3 and 4.2.7.6) by what's actually at the end of the
>> wire.  Another (probably impractical) approach is to have the resource
>> as actual content instead of just a link.
>>
>> --peter keane
>>
>> [1] http://martin.atkins.me.uk/specs/atommedia
>> [2] http://video.search.yahoo.com/mrss
>>
>>
>>> I've looked at the HTML5 RelExtentions Wiki but don't see anything there
>>> that looks like it does the job.
>>> Has anyone else needed hashed links in Atom? If so, what approach did you
>>> use to provide them? Is anyone aware of plans to introduce an "md5" or
>>> equivalent attribute to the HTML5 list?
>>> bob wyman
>>>
>>
>>
>
>
>
> --
> - James Snell
>  http://www.snellspace.com
>  [email protected]
>

Reply via email to