CacheInterface is DALMP interface to be use with the DALMP\Cache class.
The common methods are:
|Delete($key)||Delete item from the server.|
|Flush()||Flush all existing items at the server.|
|Get($key)||Retrieve item from the server.|
|Set($key, $value, $ttl = 0)||Store data at the server.|
|Stats()||Get statistics of the server.|
|X()||Return the cache object.|
All the cache backends must implement this interface in order to properly work with DALMP.
The construct for each cache backend maybe be different and it is used for defining specific options like the host, port, path, etc.
.. seealso:: `PHP Object Interfaces <http://www.php.net/manual/en/language.oop5.interfaces.php>`_.