[wp-hackers] Sending a Last-Modified header with HTML pages

[Andy Skelton]

On 11/14/06, Nathan R. Yergler <nathan at creativecommons.org> wrote:
> We're currently preparing to convert our blog to WordPress and
> discovered that it isn't emitting Last-Modified headers for page views.
> We use an HTTP accelerator, and this sort of screws with the caching.
> Is there a reason for this?  I notice that in wp-includes/classes.php
> (line 1629) there's a comment wrt only emitting them for feeds.  Can
> anyone provide some context on why WP has this behavior?

WP does not have this facility for HTML pages because there are too
many ways for the page to change with each page load, e.g. user
cookies or random bookmark selection or fuzzy time/date displays like
"5 minutes ago."

A plugin could be written to emit that header and only update it when
the database is altered, but it would not be strictly correct for most
themes.

Andy