From: Russ Allbery (rra@stanford.edu)
Date: Tue Feb 03 2004 - 15:11:37 CST
Charles Lindsey <chl@clerew.man.ac.uk> writes:
> 6. I therefore propose the following:
> Agents doing staleness checks SHOULD/MUST use either the
> composition-date or the injection-date, WHICHEVER IS THE LATER.
I'm reluctant to require both date headers to be parsed when it doesn't
seem necessary. Why not say that the injection-date should/must be used
if present, and otherwise the composition-date must be used?
> Injecting agents/moderators/etc SHOULD/MUST include the injection-date
> in the article if it is more that 24 (72/whatever) hours later than the
> composition-date and MAY/SHOULD include it regardless.
If we're going to change everything, why not just require it always be
present? Many servers are already generating NNTP-Posting-Date; we could
just use that header as-is or just rename it to something else.
> D. What happens to articles that get injected twice? It is not supposed
> to happen, except in some rather rare gatewaying situations, and with
> some particular BOFHish injectors, but it needs to be covered.
Particularly since in practice it happens all the time.
> I suspect the 2nd injector needs to overwrite whatever Injection-Date
> was present before (which is what we currently prescribe for
> Injector-Info).
No, if we're using injection-date for the staleness check, it may not ever
be overwritten or modified, for the same reason that we require the server
not modify the Date header. Doing anything else breaks Usenet's loop
detection algorithm and potentially allows reinjection of stale messages.
The choices are accepting the message with the injection-date intact or
rejecting messages with a user-supplied injection-date.
-- Russ Allbery (rra@stanford.edu) <http://www.eyrie.org/~eagle/>