On Sun, Aug 24, 2014 at 9:06 PM, Nottingham, Mark <mnotting@akamai.com>
wrote:
> FWIW - I've brought this up a number of times, IIRC on-list as well as
> privately with various folks.
>
> AIUI implementers remain unconvinced of the value here -- at least enough
> to overcome the privacy concerns (which IMO are fairly minimal, but if you
> don't see the value in something, why take the risk?).
>
> Maybe it's time to have the conversation again. I have a proposal that I
> can dust off...
>
We're exposing resource "age" via Resource-Freshness [1]... It seems
reasonable to make same data available on the client via Resource/Nav
Timing. In fact, wondering if "age" attribute could do the trick:
r = performance.getEntriesByName('https://www.example.com/resource');
r.age # nil = resource is not cacheable by HTTP cache (e.g. no-cache,
no-store, etc)
r.age # 0 = resource was just placed in HTTP cache
r.age # 1+ = resource was fetched from HTTP cache, and its age is...
For {nil, 0}, you'd know that a request was made, whereas 1+ indicates that
request was served from local HTTP cache.
The one complication I can see here is interaction with ServiceWorker..
since SW could have intercepted the request and synthesized the response on
its own, or served it from own cache. It's not clear to me how and if that
should be communicated via Resource/NavTiming.
ig
[1]
https://github.com/KenjiBaheux/resource-freshness/blob/master/specification.txt#L53
Received on Tuesday, 26 August 2014 19:30:35 UTC