Re: Our old friends, weak ETags

On 2012-07-20 07:08, Bruce Perens wrote:
> Hi Adrien,
>
> I use ETag because of an insufficiency in RFC 2616 dates: their
> resolution is one second. Updates to entities at sub-second intervals
> are possible and would result in entities with the same Last-Modified
> date. To be pedantically resolution-independent, I convert the date/time
> to a string representation of a ratio. It's presently the number of
> nanoseconds since the epoch. I encode that and an entity serial number
> in the ETag.
>
> If HTTP dates are extended to have sub-second resolution, I will
> probably be able to do without ETags.

That explains the choice of ETags, but not necessarily *weak* ETags.

(I think Apache httpd uses weak etags if it can't get a sub-second 
timestamp from the file system)

Best regards, Julian