HTTP caching

[johanjanssens]

Implement http caching support through cacheable dispatcher behavior.

Note: It's best to read up on joomlatools/joomlatools-framework#36 to if you are not familiar with http caching

Browser Caching

See: joomlatools/joomlatools-framework#183

Server caching

Implemented a server side caching mechanism through the build in Joomla caching adapters.

Cache key

The server side cache key is based on the url, user and format, by not using the contents of the page we can return the response from cache for subsequent requests for the same resource. The longer our max-age, the longer the resource will remain valid in our server cache.

Invalidation

Using a passive cache cleanup mechanism. Files are stored on disk for max 1 week, after which they are garbage collected. This ensure that local cache is cleared for url's that are not requested, or no longer exists.

Configuration

Configuration is provided at two levels:

1. Global

Globally the cache can be configured by adding a docman.php file to the /joomla-pages root folder with the following config options:

<?php
  return array(
     'cache'         => true,
     'cache_time'    => 7200, //(seconds)
     'cache_private' => false,
);

2. Frontmatter

The cache can be disabled per page and the cache time can also be set. The frontmatter property is

process:
     cache: [true, false,  time]

The time is specified in seconds.