Data Cache Object

The Data_Cache is Skeleton's class for caching data which may be computationally expensive to regenerate, such as the result of complex datatabase queries. This object cache is defined in skeleton/third_party/bkader/class-cache-object.php.

Do not use the class directly in your code when developing your application, but use the data_cache_x functions listed below.

By default, the object cache is non-persistent. This means that data stored in the cache resides in memory only and only for the duration of the request. Cached data will not be stored persistently across page loads.

Data_Cache functions

Most of these function take a:

• $ey: the key to indicate the value.
• $data: the value to want to store.
• $group (optional): This is a way of grouping data within the cache. Allows you to use the same key accross different groups.

data_cache_add

data_cache_add($key, $data, $group);

This function adds data to the cache if the cache key doesn't already exist. If it does exist, the data is not added and the function returns false.

data_cache_add_groups

data_cache_add_groups($groups);
// 'group1, group2...' OR array('group1', 'group2')

Sets the list of global cache groups.

data_cache_set

data_cache_set($key, $data, $group);

Adds data to the cache. If the cache key already exists, then it will be overwritten; if not then it will be created.

data_cache_get

data_cache_get($key, $group);

Returns the value of the cached object, or false if the cache key doesn't exist.

To disambiguate a cached false from a non-existing key, you should do absolute testing of $found, which is passed by reference, against false: if $found === false, the key does not exist.

data_cache_replace

data_cache_replace($key, $data, $group);

Replaces the contents in the cache, if contents already exist.

data_cache_delete

data_cache_delete($key, $group);

Removes the contents of the cache key in the group if it exists.

data_cache_reset

data_cache_replace($key, $data, $group);

Resets all cache keys.

data_cache_flush

data_cache_replace($key, $data, $group);

Clears the object cache of all data.