Re: #290: Motivate one-year limit for Expires

[Mark Nottingham <[e-mail]>]

On 24/07/2011, at 2:06 PM, Willy Tarreau wrote:
>> 
>> Why should they ignore if they don't have the problem?
> 
> How can they know whether there is a problem ? Let's imagine that my server
> is set one year in the future and emits Expires dates one year and a month
> away. What I understand is that people were suggesting that more than one
> year was a sign of misconfiguration which is the case here. So probably that
> ignoring the date is easier to recover from than keeping the object in cache
> for that long.

I don't understand. 


>> Besides which, this would be introducing a requirement that makes several previously conformant implementations non-conformant. 
> 
> Well, not exactly since in the past it was a SHOULD NOT, so we don't know
> how recipients consider larger values (some may already decide to ignore
> them or to bound them to 1 year), which is the spirit of your proposal
> anyway.

No, there is no current requirement in HTTP for caches to impose the one-year limit; this would be a new requirement.


> I feel like two distinct issues are being discussed here :
>  - how to avoid recipient's wrong behaviour
>  - how to deal with an error at the server's
> 
> I was dicussing the second point but you appear to be discussing the former
> (which I agree with).
> 
> Maybe the second point is so marginal that it can safely be ignored ?
> 
> Regards,
> Willy
> 

--
Mark Nottingham   http://www.mnot.net/