Erica,
IMO, your caching should take place on the PHP side of things, not Apache
or any Apache modules (save for maybe mod_php).
Depending on how frequently the cache should refresh, I would either have
(1) PHP write the newest response to a file and check the timestamp of the
file to check if the cachefile should be updated,
(2) Don't use PHP called from a webserver, but rather use PHP called from a
cron job, or
(3) find out how to use PHP to cache itself (I'm pretty sure Apache won't
cache PHP, ASP, etc.)
For help on any three of these things, I would recommend asking at a
PHP-specific forum/mailing list or on www.php.net (the comments on that site
are sometimes extremely helpful).
Regards,
David Wortham
On 3/5/07, Erica Zhang <[EMAIL PROTECTED]> wrote:
Hi,
I want to develop a filter module to cache responses for XMLHttp
requests for Apache. Before that, I have tried to configure using
mod_cache. I found that it could not be used to cache responses for
XMLHttp requests. However, I am not sure about this, because I am new to
web applications. So before beginning to develop a new module to do this
function, I want to make sure that. Is there some expert tell me about
your idea on this topic or experiences ?
I tried to give more details below:
For mod_cache, I use httpd.conf to configure it:
MaxKeepAliveRequests 10000
<IfModule mpm_winnt.c>
ThreadsPerChild 1900
MaxRequestsPerChild 10000
</IfModule>
LoadModule cache_module modules/mod_cache.so
<IfModule mod_cache.c>
CacheForceCompletion 100
CacheDefaultEXPire 3600
CacheMaxExpire 86400
CacheLastModifiedFactor 0.1
LoadModule disk_cache_module modules/mod_disk_cache.so
<IfModule mod_disk_cache.c>
CacheEnable disk /
CacheRoot c:/cacheroot
CacheSize 327680
CacheDirLength 4
CacheDirLevels 5
CacheGcInterval 4
</IfModule>
#LoadModule mem_cache_module modules/mod_mem_cache.so
<IfModule mod_mem_cache.c>
CacheEnable mem /
MCacheSize 8192
MCacheMaxObjectCount 10000
MCacheMinObjectSize 1
MCacheMaxObjectSize 51200
</IfModule>
</IfModule>
On client, I use ajax technology and XMLHttpRequest and on server, I
use php script.
...
header("Cache-Control: public"); // HTTP/1.1
header("Expires: " .gmdate ("D, d M Y H:i:s", time() + 60 * 10). " GMT");
header( "Last-Modified: " .gmdate( 'D, d M Y H:i:s' ). " GMT" );
echo $response;
....
I think apache cache should catch my response produced by PHP. Until
now, I do not think there is something wrong in my code or
configuration. So I conclude that mod_cache could not catch the
responses for XMLHttp requests.
Regards,
Erica
