Added Cache class and made adjustments to Config to default the variables to false.

classes/Cache.php

@@ -0,0 +1,211 @@
+<?php
+
+/**
+ * Caching System for PICKLES
+ *
+ * PHP version 5
+ *
+ * Licensed under The MIT License
+ * Redistribution of these files must retain the above copyright notice.
+ *
+ * @author    Josh Sherman <josh@gravityblvd.com>
+ * @copyright Copyright 2007-2011, Josh Sherman
+ * @license   http://www.opensource.org/licenses/mit-license.html
+ * @package   PICKLES
+ * @link      http://p.ickl.es
+ */
+
+/**
+ * Cache Class
+ *
+ * Wrapper class for Memcache() to allow for better error handling when the
+ * Memcached server is unavailable. Designed around the syntax for Memcached()
+ * to allow for an easier transistion to the aforementioned in the future. I
+ * don't entirely remember specifics, but the reason for not using Memcached()
+ * was due to an unexplainable bug in the version in the repository for Ubuntu
+ * 10.04 LTS. Memcached() does support more of the memcached protocol and will
+ * eventually be what PICKLES uses.
+ *
+ * Requires php5-memcache
+ *
+ * @link http://us.php.net/manual/en/book.memcache.php
+ * @link http://packages.ubuntu.com/lucid/php5-memcache
+ * @link http://www.memcached.org/
+ */
+class Cache extends Object
+{
+	/**
+	 * Hostname for the Memcached Server
+	 *
+	 * @access private
+	 * @var    string
+	 */
+	private $hostname = null;
+
+	/**
+	 * Port to use to connect
+	 *
+	 * @access private
+	 * @var    integer
+	 */
+	private $port = null;
+
+	/**
+	 * Connection resource to Memcached
+	 *
+	 * @access private
+	 * @var    object
+	 */
+	private $connection = null;
+
+	/**
+	 * Constructor
+	 *
+	 * Sets up our connection variables.
+	 *
+	 * @param string $hostname optional hostname to connect to
+	 * @param string $database optional port to use
+	 */
+	public function __construct($hostname = null, $port = null)
+	{
+		parent::__construct();
+
+		if ($this->config->pickles['cache'])
+		{
+			if (isset($this->config->datasources[$this->config->pickles['cache']]))
+			{
+				$datasource = $this->config->datasources[$this->config->pickles['cache']];
+
+				if (isset($datasource['hostname'], $datasource['port']))
+				{
+					$this->hostname = $datasource['hostname'];
+					$this->port     = $datasource['port'];
+				}
+			}
+		}
+	}
+
+	/**
+	 * Destructor
+	 *
+	 * Closes the connection when the object dies.
+	 */
+	public function __destruct()
+	{
+		if ($this->connection)
+		{
+			$this->connection->close();
+		}
+	}
+
+	/**
+	 * Get Instance
+	 *
+	 * Let's the parent class do all the work.
+	 *
+	 * @static
+	 * @param  string $class name of the class to instantiate
+	 * @return object self::$instance instance of the Cache class
+	 */
+	public static function getInstance($class = 'Cache')
+	{
+		return parent::getInstance($class);
+	}
+
+	/**
+	 * Opens Connection
+	 *
+	 * Establishes a connection to the memcached server.
+	 */
+	public function open()
+	{
+		if ($this->connection === null)
+		{
+			$this->connection = new Memcache();
+			$this->connection->connect($this->hostname, $this->port);
+		}
+
+		return true;
+	}
+
+	/**
+	 * Get Key
+	 *
+	 * Gets the value of the key and returns it.
+	 *
+	 * @param  string $key key to retrieve
+	 * @return mixed  value of the requested key, false if not set
+	 */
+	public function get($key)
+	{
+		if ($this->open())
+		{
+			return $this->connection->get($key);
+		}
+
+		return false;
+	}
+
+	/**
+	 * Set Key
+	 *
+	 * Sets key to the specified value. I've found that compression can lead to
+	 * issues with integers and can slow down the storage and retrieval of data
+	 * (defeats the purpose of caching if you ask me) and isn't supported. I've
+	 * also been burned by data inadvertantly being cached for infinity, hence
+	 * the 5 minute default.
+	 *
+	 * @param  string  $key key to set
+	 * @param  mixed   $value value to set
+	 * @param  integer $expiration optional expiration, defaults to 5 minutes
+	 * @return boolean status of writing the data to the key
+	 */
+	public function set($key, $value, $expire = 300)
+	{
+		if ($this->open())
+		{
+			return $this->connection->set($key, $value, 0, $expire);
+		}
+
+		return false;
+	}
+
+	/**
+	 * Delete Key
+	 *
+	 * Deletes the specified key.
+	 *
+	 * @param  string $key key to delete
+	 * @return boolean status of deleting the key
+	 */
+	public function delete($key)
+	{
+		if ($this->open())
+		{
+			return $this->connection->delete($key);
+		}
+
+		return false;
+	}
+
+	/**
+	 * Increment Key
+	 *
+	 * Increments the value of an existing key.
+	 *
+	 * @param  string $key key to increment
+	 * @return boolean status of incrementing the key
+	 * @todo   Wondering if I should check the key and set to 1 if it's new
+	 */
+	public function increment($key)
+	{
+		if ($this->open())
+		{
+			return $this->connection->increment($key);
+		}
+
+		return false;
+	}
+}
+
+?>