Re: What is a Version?

Am 12.03.2026 um 19:01 schrieb Nico Williams:
> On Thu, Mar 12, 2026 at 06:11:55PM +0100, Julian Reschke wrote:
>> [...]
> 
> I'm asking how to get a URI for the version _alone_, not the versioned
> resource.  If we're talking about a VCS application we'd be talking
> about obtaining a URI for a "commit" that might involve many resources.
> 
> Given:
> 
>    GET /some/resource
> 
>    200 Ok
>    Version: 12345
> 
> find a URI for a commit named 12345 that affected /some/resource and
> possibly others.

Ok, so let's distinguish between "version of a resource", "resource that 
has versions" ("version-controlled" in WebDAV), and "commit" or "change 
list"; just to avoid overloading "version".

>>>> In practice, you can't define new fields that support conditional requests
>>>> (unless you control both ends and all intermediaries). For conditional
>>>> reads, that would be harmless (no optimizations), for range requests and
>>>> write conflict prevention it would be a major problem.
>>>
>>> You could look before jumping.
>>
>> Opt-in? How does this work with caches?
> 
> Ah, good point.  We'd need a way to discover cache functionality.

Good luck.

>> Having a URI for "the representation of the resource when it (the
>> representation) had this etag" could be useful when looking at the history
>> of a resource. FWIW, we have a response field for that in HTTP.
> 
> What header is that?  Location:?

C-L (I think, can be confusing).

Best regards, Julian

Received on Thursday, 12 March 2026 18:17:43 UTC