Re: [htmltmpl] cache-ing question

[Thilo P. <thi...@we...>]

Hi,


> I have a mod_perl/CGI::Application program that I've written that 
> populates
> a HTML::Template with a list of files that are on the server.

> I'd like to cache that list, based on the URL, so that it doesn't have 
> to do
> a readdir(), grep() and also a TreeBuilder to get the TITLE everytime
> someone visits the program.
>
> Has anyone done something similar and can share any tips?

Since you are using mod_perl, you can just create save your result in 
any variable that stays around.
Assuming your data is stored in a hashref (or any other scalar) you 
could do something like

sub get_directory_data{
	return $MyCache::DirectoryData if defined $MyCache::DirectoryData;
	# create the cache
	my $data =  .... do something here ...
	$MyCache::DirectoryData = $data;
	return $data;
}

if you want to refresh your cache after some time, you can also set up 
a timestamp.


> Does the cache-ing in HTML::Template also cache the params?

No, and that would be a bad idea, because usually you do not want to 
have any old params around but start out fresh.

> If not, then
> what is it cache-ing?  Just the template itself?

It is caching a parsed instance of the template.
Using a cache saves you the time to read the template from the disk and 
transforming it into the internal parse-tree structure.


> If it is, it looks like in
> the docs, it caches, based on the filename - so if I'm using 1 
> template for
> all those lists, then should I break it up into (the number of list
> possibilites # {14}) templates?

If those 14 have the same HTML and only differ in the content of the 
parameters, do not break it up.


Cheers,

Thilo