Re: [apps-discuss] HTTP header field for "URI lifetime"

[Graham Klyne <[e-mail]>]

On 20/05/2015 10:50, Erik Wilde wrote:
> hello graham.
>
> On 2015-05-20 11:30, Graham Klyne wrote:
>> Following the subsequent couple of messages, this seems like the goals
>> might be somewhat experimental.  For such purposes, I think the desired
>> effect *could* be achieved using a Link: header with a URI link
>> relation; e.g., something like:
>>      Link: <http://example.org/RetentionInformation>;
>>            rel=http://linktype.example.org/retentionPolicy/
>> (If you don't want to store the retention information separately, maybe
>> a data: URI?)
>> I see an advantage of such an approach is that you could experiment with
>> different kinds of retention information by changing the link relation
>> URI, and the approach might play nicely with a wider linked data
>> infrastructure. Just a thought.
>
> interesting idea. however, this shifts the problem from the header field to a
> well-known link relation *and* and well-known representation to even get the
> date. the reason why we were discussing a header field was also that it would be
> very clear to find in the uniform interface and very easy to process, and by
> default, no link would need to be dereferenced to get to the most important
> piece of information. so the potential header field might look something like this:
>
> Sunset: "Mon, 06 Jul 2015 09:00:00 GMT", reason = "We're shutting down for
> good", reasonURI = http://example.com/goodbye.html
>
> and both the human-readable label and the link to the sunset information
> resource would be optional. this seems to be a bit more explicit than what
> you're suggesting, but i do agree that in the end, both approaches are
> representing (almost) the same information.

Fair enough.  I thought it might be interesting to see how close to this one 
might get with a Link: header:

  Link: 
<data:,2015-07-06T09:00:00Z,reason=%22We're%20shutting%20down%20for%20good%22,reasonURI=http://example.com/goodbye.html>,rel=http://linktype.example.com/sunset

It's clearly not as pretty, but I can't tell how important that might be.

#g
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