[tbnl-devel] Last-Modified / If-Modified-Since Headers

[pete-tbnl-dev at kazmier.com]

On Wed, Jul 14, 2004 at 10:11:50AM +0200, Edi Weitz wrote:
> > I've built sites that use template engines that are backed by a
> > "data miner" that refreshes the context used to fill templates on a
> > periodic basis.  Web-based reporting interfaces can take advantage
> > of this scenario.
> 
> But why then don't you serve these pages statically directly from
> Apache?

In this specific example, the data model can be modified by other
external events as well.  Furthermore, there are numerous templates that
provide visibility into the data model and each is customized to the
user.  I.e., the template contains the username, last login, etc.  It
isn't practical to store 'n' copies of output.  

In addition, each page includes a Refresh header (for 5 minutes) as
these reports are meant to be used by level 1 and level 2 support teams
that leave them open indefinitely.  Thus, when a change occurs to the
data model, we can simply use getLastModified to invalidate all of the
pages stored in cache on the client side.