EVE-KILL / zKillboard

classes/RedisCache.php

<?php
/* zCache
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/**
 * Redis Cache Class
 * 
 * @use Redis (https://github.com/nicolasff/phpredis)
 *
 */
class RedisCache extends AbstractCache
{
	/**
	 * Redis object instance
	 *
	 * @var object Redis object
	 */
	private $_redis;

	/**
	 * Instantiates the `Redis` object and connects it to the configured server.
	 *
	 * @return void

Adding a @return annotation to constructors is generally not recommended as a constructor does not have a meaningful return value.

	 */
	function __construct()

It is generally recommended to explicitly declare the visibility for methods.

It is recommend to declare an explicit visibility for __construct.

	{
		global $redisServer, $redisPort;

		if (!$this->_redis) {
			$this->_redis = new Redis();
		}

		if (substr($redisServer, 0, 7) == "unix://") {
			$this->_redis->pconnect(substr($redisServer, 7), 0.0, null, 0);
		} else {
			$this->_redis->pconnect($redisServer, $redisPort, 0.0, null, 0);
		}
	}

	/**
	 * Sets expiration time for cache key
	 *
	 * @param string $key The key to uniquely identify the cached item
	 * @param mixed $timeout A `strtotime()`-compatible string or a Unix timestamp.
	 * @return boolean
	 */
	protected function _expireAt($key, $timeout)
	{
		return $this->_redis->expireAt($key, is_int($timeout) ? $timeout : strtotime($timeout));
	}

	/**
	 * Read value from the cache
	 *
	 * @param string $key The key to uniquely identify the cached item
	 * @return mixed
	 */
	public function get($key)
	{
		return $this->_redis->get($key);
	}

	/**
	 * Write value to the cache
	 *
	 * @param string $key The key to uniquely identify the cached item
	 * @param mixed $value The value to be cached
	 * @param null|string $timeout A strtotime() compatible cache time.
	 * @return boolean
	 */
	public function set($key, $value, $timeout)
	{
		$result = $this->_redis->set($key, $value);
		return $result ? $this->_expireAt($key, $timeout) : $result;
	}

	/**
	 * Override value in the cache
	 *
	 * @param string $key The key to uniquely identify the cached item
	 * @param mixed $value The value to be cached
	 * @param null|string $timeout A strtotime() compatible cache time.
	 * @return boolean
	 */
	public function replace($key, $value, $timeout)
	{
		return  $this->_redis->set($key, $value, $timeout);
	}

	/**
	 * Delete value from the cache
	 *
	 * @param string $key The key to uniquely identify the cached item
	 */
	public function delete($key)
	{
		return (boolean) $this->_redis->del($key);
	}

	/**
	 * Performs an atomic increment operation on specified numeric cache item.
	 *
	 * Note that if the value of the specified key is *not* an integer, the increment
	 * operation will have no effect whatsoever. Redis chooses to not typecast values
	 * to integers when performing an atomic increment operation.
	 *
	 * @param string $key Key of numeric cache item to increment
	 * @return Closure Function returning item's new value on successful increment, else `false`
	 */
	public function increment($key, $step = 1, $timeout = 0)
	{
		if ($timeout) {
			$this->_expireAt($key, $timeout);
		}
		return $this->_redis->incr($key, $step);
	}

	/**
	 * Performs an atomic decrement operation on specified numeric cache item.
	 *
	 * Note that if the value of the specified key is *not* an integer, the decrement
	 * operation will have no effect whatsoever. Redis chooses to not typecast values
	 * to integers when performing an atomic decrement operation.
	 *
	 * @param string $key Key of numeric cache item to decrement
	 * @param integer $step Offset to decrement - defaults to 1
	 * @param integer $timeout A strtotime() compatible cache time.
	 * @return Closure Function returning item's new value on successful decrement, else `false`
	 */
	public function decrement($key, $step = 1, $timeout = 0)
	{
		if ($timeout) {
			$this->_expireAt($key, $timeout);
		}
		return $this->_redis->decr($key, $step);
	}

	/**
	 * Clears user-space cache
	 *
	 * @return boolean|null
	 */
	public function flush()
	{
		$this->_redis->flushdb();
	}

}