Re: New Version Notification for draft-toomim-httpbis-versions-00.txt

Julian:
> Michael Toomim:
>> ...
>> The main problem with ETag, though, is that it marks *unique content*
>> rather than *unique time*. If you mutate the state of the resource from
>> "foo" to "bar" and then back to "foo", you'll revert to the same ETag,
>> even though this is at a different point in time. This breaks
>> collaborative editing algorithms.
>> ...
>
> It doen't have to be implemented that way. For instance, AFAIR,
> Subversion just uses the version number as Etag, and that's just fine.

Ah, good catch!

We do need a semantic for "a point in time", but it's true that instead 
of introducing a new "Version" header, we could also introduce a header 
or parameter syntax that constrains the meaning of the ETag header. 
However, ETag would also need to support a list of strings, instead of a 
single string, to represent merge versions from time to time.

Received on Thursday, 25 July 2024 09:36:49 UTC