NAME

HTML::Mason::Cache::BaseCache - Base cache object

DESCRIPTION

This is the base module for all cache implementations used in Mason. It provides a few additional methods on top of Cache::BaseCache in Dewitt Clinton's Cache::Cache package.

An object of this class is returned from $m->cache.

METHODS

clear ()

Remove all values in the cache.

get (key, [%params])

Returns the value associated with key or undef if it is non-existent or expired. This is extended with the following optional name/value parameters:

busy_lock => duration

If the value has expired, set its expiration time to the current time plus duration (instead of removing it from the cache) before returning undef. This is used to prevent multiple processes from recomputing the same expensive value simultaneously. The duration may be of any form acceptable to set.

expire_if => sub

If the value exists and has not expired, call sub with the cache object as a single parameter. If sub returns a true value, expire the value.

get_object (key)

Returns the underlying Cache::Object object associated with key. The most useful methods on this object are

$co->get_created_at();    # when was object stored in cache
$co->get_accessed_at();   # when was object last accessed
$co->get_expires_at();    # when does object expire

expire (key)

Expires the value associated with key, if it exists. Differs from remove only in that the cache object is left around, e.g. for retrieval by get_object.

remove (key)

Removes the cache object associated with key, if it exists.

set (key, data, [duration])

Associates data with key in the cache. duration indicates the time until the value should be erased. If duration is unspecified, the value will never expire by time.

$expires_in may be a simple number of seconds, or a string of the form "[number] [unit]", e.g., "10 minutes". The valid units are s, second, seconds, sec, m, minute, minutes, min, h, hour, hours, d, day, days, w, week, weeks, M, month, months, y, year, and years.