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diff --git a/user_guide_src/source/libraries/caching.rst b/user_guide_src/source/libraries/caching.rst deleted file mode 100644 index a7081ec6b..000000000 --- a/user_guide_src/source/libraries/caching.rst +++ /dev/null @@ -1,279 +0,0 @@ -############## -Caching Driver -############## - -CodeIgniter features wrappers around some of the most popular forms of -fast and dynamic caching. All but file-based caching require specific -server requirements, and a Fatal Exception will be thrown if server -requirements are not met. - -.. contents:: - :local: - -.. raw:: html - - <div class="custom-index container"></div> - -************* -Example Usage -************* - -The following example will load the cache driver, specify `APC <#alternative-php-cache-apc-caching>`_ -as the driver to use, and fall back to file-based caching if APC is not -available in the hosting environment. - -:: - - $this->load->driver('cache', array('adapter' => 'apc', 'backup' => 'file')); - - if ( ! $foo = $this->cache->get('foo')) - { - echo 'Saving to the cache!<br />'; - $foo = 'foobarbaz!'; - - // Save into the cache for 5 minutes - $this->cache->save('foo', $foo, 300); - } - - echo $foo; - -You can also prefix cache item names via the **key_prefix** setting, which is useful -to avoid collisions when you're running multiple applications on the same environment. - -:: - - $this->load->driver('cache', - array('adapter' => 'apc', 'backup' => 'file', 'key_prefix' => 'my_') - ); - - $this->cache->get('foo'); // Will get the cache entry named 'my_foo' - -*************** -Class Reference -*************** - -.. php:class:: CI_Cache - - .. php:method:: is_supported($driver) - - :param string $driver: the name of the caching driver - :returns: TRUE if supported, FALSE if not - :rtype: bool - - This method is automatically called when accessing drivers via - ``$this->cache->get()``. However, if the individual drivers are used, - make sure to call this method to ensure the driver is supported in the - hosting environment. - :: - - if ($this->cache->apc->is_supported()) - { - if ($data = $this->cache->apc->get('my_cache')) - { - // do things. - } - } - - .. php:method:: get($id) - - :param string $id: Cache item name - :returns: Item value or FALSE if not found - :rtype: mixed - - This method will attempt to fetch an item from the cache store. If the - item does not exist, the method will return FALSE. - :: - - $foo = $this->cache->get('my_cached_item'); - - .. php:method:: save($id, $data[, $ttl = 60[, $raw = FALSE]]) - - :param string $id: Cache item name - :param mixed $data: the data to save - :param int $ttl: Time To Live, in seconds (default 60) - :param bool $raw: Whether to store the raw value - :returns: TRUE on success, FALSE on failure - :rtype: string - - This method will save an item to the cache store. If saving fails, the - method will return FALSE. - :: - - $this->cache->save('cache_item_id', 'data_to_cache'); - - .. note:: The ``$raw`` parameter is only utilized by APC and Memcache, - in order to allow usage of ``increment()`` and ``decrement()``. - - .. php:method:: delete($id) - - :param string $id: name of cached item - :returns: TRUE on success, FALSE on failure - :rtype: bool - - This method will delete a specific item from the cache store. If item - deletion fails, the method will return FALSE. - :: - - $this->cache->delete('cache_item_id'); - - .. php:method:: increment($id[, $offset = 1]) - - :param string $id: Cache ID - :param int $offset: Step/value to add - :returns: New value on success, FALSE on failure - :rtype: mixed - - Performs atomic incrementation of a raw stored value. - :: - - // 'iterator' has a value of 2 - - $this->cache->increment('iterator'); // 'iterator' is now 3 - - $this->cache->increment('iterator', 3); // 'iterator' is now 6 - - .. php:method:: decrement($id[, $offset = 1]) - - :param string $id: Cache ID - :param int $offset: Step/value to reduce by - :returns: New value on success, FALSE on failure - :rtype: mixed - - Performs atomic decrementation of a raw stored value. - :: - - // 'iterator' has a value of 6 - - $this->cache->decrement('iterator'); // 'iterator' is now 5 - - $this->cache->decrement('iterator', 2); // 'iterator' is now 3 - - .. php:method:: clean() - - :returns: TRUE on success, FALSE on failure - :rtype: bool - - This method will 'clean' the entire cache. If the deletion of the - cache files fails, the method will return FALSE. - :: - - $this->cache->clean(); - - .. php:method:: cache_info() - - :returns: Information on the entire cache database - :rtype: mixed - - This method will return information on the entire cache. - :: - - var_dump($this->cache->cache_info()); - - .. note:: The information returned and the structure of the data is dependent - on which adapter is being used. - - .. php:method:: get_metadata($id) - - :param string $id: Cache item name - :returns: Metadata for the cached item - :rtype: mixed - - This method will return detailed information on a specific item in the - cache. - :: - - var_dump($this->cache->get_metadata('my_cached_item')); - - .. note:: The information returned and the structure of the data is dependent - on which adapter is being used. - -******* -Drivers -******* - -Alternative PHP Cache (APC) Caching -=================================== - -All of the methods listed above can be accessed without passing a -specific adapter to the driver loader as follows:: - - $this->load->driver('cache'); - $this->cache->apc->save('foo', 'bar', 10); - -For more information on APC, please see -`http://php.net/apc <http://php.net/apc>`_. - -File-based Caching -================== - -Unlike caching from the Output Class, the driver file-based caching -allows for pieces of view files to be cached. Use this with care, and -make sure to benchmark your application, as a point can come where disk -I/O will negate positive gains by caching. - -All of the methods listed above can be accessed without passing a -specific adapter to the driver loader as follows:: - - $this->load->driver('cache'); - $this->cache->file->save('foo', 'bar', 10); - -Memcached Caching -================= - -Multiple Memcached servers can be specified in the memcached.php -configuration file, located in the _application/config/* directory. - -All of the methods listed above can be accessed without passing a -specific adapter to the driver loader as follows:: - - $this->load->driver('cache'); - $this->cache->memcached->save('foo', 'bar', 10); - -For more information on Memcached, please see -`http://php.net/memcached <http://php.net/memcached>`_. - -WinCache Caching -================ - -Under Windows, you can also utilize the WinCache driver. - -All of the methods listed above can be accessed without passing a -specific adapter to the driver loader as follows:: - - $this->load->driver('cache'); - $this->cache->wincache->save('foo', 'bar', 10); - -For more information on WinCache, please see -`http://php.net/wincache <http://php.net/wincache>`_. - -Redis Caching -============= - -Redis is an in-memory key-value store which can operate in LRU cache mode. -To use it, you need `Redis server and phpredis PHP extension <https://github.com/phpredis/phpredis>`_. - -Config options to connect to redis server must be stored in the application/config/redis.php file. -Available options are:: - - $config['socket_type'] = 'tcp'; //`tcp` or `unix` - $config['socket'] = '/var/run/redis.sock'; // in case of `unix` socket type - $config['host'] = '127.0.0.1'; - $config['password'] = NULL; - $config['port'] = 6379; - $config['timeout'] = 0; - -All of the methods listed above can be accessed without passing a -specific adapter to the driver loader as follows:: - - $this->load->driver('cache'); - $this->cache->redis->save('foo', 'bar', 10); - -For more information on Redis, please see -`http://redis.io <http://redis.io>`_. - -Dummy Cache -=========== - -This is a caching backend that will always 'miss.' It stores no data, -but lets you keep your caching code in place in environments that don't -support your chosen cache.
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