About modules/metadata/mod_expires.c (apache 2.2)

[Julien Perez <ju...@epsylonia.net>]

Hello everybody,

While setting up a reverse proxy squid + apache w/ mod_expires.c in order to
decrease the load on the web server, I discovered that mod_expires.c was
working by checking the mimetype of the content generated by the web server
(i.e. cgi or static file) and not the mimetype of the file that was used to
generat the output. Could someone explain me why it is so ?

For me, it would make more sense to be able to differentiate  what was
generated by executing a CGI script and what was generated by reading a
static file, especially in caching context like it is the case here. Indeed,
I don't think you want to give the same expiration date to a static file
(unlikely to change every hour) to a content generated by, let's say, a php
script that is using a database (more likely to change every minute).

The problem (im my opinion) is that Apache cannot differentiate between
those 2 types of stream and, therefore, setting up the cache expiration time
for text/html is working both for static files and for cgi scripts outputing
text/html content.

Is there any plan to change the behavior of mod_expires.c to differentiate
between those 2 kinds of data stream before setting the Expires: field of
header ?

Maybe I'm completely wrong in my observation or there is a part of the big
picture I didn't see, any explanation welcome :)

Thanks

Julien, beginner in modules development

Re: About modules/metadata/mod_expires.c (apache 2.2)

[Joshua Slive <jo...@slive.ca>]

On 8/26/07, Julien Perez <ju...@epsylonia.net> wrote:
> Hello everybody,
>
> While setting up a reverse proxy squid + apache w/ mod_expires.c in order to
> decrease the load on the web server, I discovered that mod_expires.c was
> working by checking the mimetype of the content generated by the web server
> ( i.e. cgi or static file) and not the mimetype of the file that was used to
> generat the output. Could someone explain me why it is so ?

I believe that is exactly what most people expect and want. For
example, people want different expiration times for html versus gif
versus css. Many people would be annoyed if html generated by cgi was
not matched.

For what you want, you can use ExpiresDefault scoped in a <Directory>
or <Files> section to apply only to the specific content that you
need.

Joshua.