MarkupCache by Ryan Cramer

This core module enables you to cache any individual pieces of generated markup.

I'm working on a site now that has 500+ cities in a select pulldown generated from ProcessWire pages. Loading 500+ pages and creating the select options on every pageview isn't terribly efficient, but I didn't want to cache the whole template because it needed to support dynamic parameters in the URL. The solution was to cache just the code that generated the select options. Here's an example:

$cache = $modules->get("MarkupCache");

if(!$data = $cache->get("something")) {

    // ... generate your markup in $data ...

    $cache->save($data);

}

echo $data;

I left the markup generation code (the part that gets cached) out of the example above to keep it simple. Below is the same example as above, but filled out with code that finds the pages and generates the markup (the part that gets cached):

$cache = $modules->get("MarkupCache");

if(!$data = $cache->get("city_options")) {

    foreach($pages->find("template=city, sort=name") as $city) {

        $data .= "<option value='{$city->id}'>{$city->title}</option>";

    }

    $cache->save($data);

}

echo $data;

That was an example of a place where this module might be useful, but of course this module can used to cache any snippets of code. By default, it caches the markup for an hour. If you wanted to cache it for a longer or shorter amount of time, you would just specify the number of seconds as a second parameter in the get() call. For example, this would keep a 60-second cache of the data:

$cache->get("city_options", 60);