Feature Proposal: Increase max-age for static webs

Motivation

in Foswiki.pm we hardcode Cache-Control: max-age=0. This prevents the admin from over-riding it from apache

In the use case I have, it would be reasonable to increase the max-age of the System web topics to at least a few minutes (The WebLeftBarWebList topic and other Sidebar dynamics being the most risky)

This then will allow us to use jqLoader to delay load the weblist - giving the impression of a faster wiki when there are lots of webs.

Description and Documentation

mostly I'd like to be able to

• disable max-age setting from our scripts
• increase the max-age for requests (non-url param requests) to topics in particular webs.

Examples

Impact

WhatDoesItAffect:

%WHATDOESITAFFECT%

edit

Implementation

-- Contributors: SvenDowideit - 17 Apr 2012

Discussion

I've implemented it, with things disabled by default, as you really do need to know what you're doing.

#---++ Browser Cache max-age
# **PERL EXPERT**
# Disable or change the HTTP Cache-Control header. Foswiki defaults to 
# =Cache-Control: max-age=0= which recomends to the browser that it should 
# ask foswiki if the topic has changed. If you have a web that does not change
# (like System), you can get the browser to use its cache by setting ={'System' => ''}=
# you can also set =max-age=28800= (for 8 hours), or any other of the 
# =Cache-Control= directives.
# <br />
# Setting the CacheControl to '' also allows you to manage this from your web 
# server (which will not over-ride the setting provided by the application), thus enabling
# web server based caching policies. When the user receives a browser-cache topic, 
# they can force a refresh using ctrl-r
# <br />
# this hash must be explicitly set per web or sub-web.
$Foswiki::cfg{BrowserCacheControl} = {};

however, while it works on my test system, its not working on http://trunk.foswiki.org/System - so it would be good to know why.

-- SvenDowideit - 10 Oct 2012