[Zope-dev] Last-modified and bobobase_modification_time
Dieter Maurer
dieter@handshake.de
Tue, 18 Jun 2002 21:29:36 +0200
Wei He writes:
> ...
> 2. From the website developers' point of view, there are already many
> guidlines on how to create a good webpage. Among them are using the HTTP
> Last-modification header to take the advantages of client cache.
I think you overestimate the importance of accurate "Last-Modified"
headers.
In order for caching to be allowed, there must
either be a "Last-Modified" or (alternatively) an "Etag" header.
However, the value of the "Last-Modified" is almost irrelevant
for caching. I think, it is only used when a HTTP cache
validates on object, in that is uses this date in an
"If-Modified-Since" request.
I would use "Expires" and "Cache-Control" for cache control.
Dieter