[Solar-svn] Revision 2791

[pmjones at solarphp.com]

branch: Solar_Cache_Adapter_Var: [NEW] A weak cache controller that stores cache entries to an object property.  Of course, when the script ends, the cache goes away.


Added: branches/orm/Solar/Cache/Adapter/Var.php
===================================================================
--- branches/orm/Solar/Cache/Adapter/Var.php	                        (rev 0)
+++ branches/orm/Solar/Cache/Adapter/Var.php	2007-09-29 01:14:49 UTC (rev 2791)
@@ -0,0 +1,187 @@
+<?php
+/**
+ * 
+ * Variable (in-memory) cache controller.
+ * 
+ * @category Solar
+ * 
+ * @package Solar_Cache
+ * 
+ * @author Paul M. Jones <pmjones at solarphp.com>
+ * 
+ * @license http://opensource.org/licenses/bsd-license.php BSD
+ * 
+ * @version $Id$
+ * 
+ */
+
+/**
+ * 
+ * Variable (in-memory) cache controller.
+ * 
+ * Stores cache entries to an object variable.  This means that entries are
+ * available for the duration of the script, but are cleared out at the end
+ * of the script.
+ * 
+ * @category Solar
+ * 
+ * @package Solar_Cache
+ * 
+ */
+class Solar_Cache_Adapter_Var extends Solar_Cache_Adapter {
+    
+    /**
+     * 
+     * Cache entries.
+     * 
+     * @var array
+     * 
+     */
+    protected $_entry = array();
+    
+    /**
+     * 
+     * Expiration timestamps for each cache entry.
+     * 
+     * @var array
+     * 
+     */
+    protected $_expires = array();
+    
+    /**
+     * 
+     * Constructor.
+     * 
+     * @param array $config User-provided configuration values.
+     * 
+     */
+    public function __construct($config = null)
+    {
+        parent::__construct($config);
+    }
+    
+    /**
+     * 
+     * Sets cache entry data.
+     * 
+     * @param string $key The entry ID.
+     * 
+     * @param mixed $data The data to write into the entry.
+     * 
+     * @return bool True on success, false on failure.
+     * 
+     */
+    public function save($key, $data)
+    {
+        if (! $this->_active) {
+            return;
+        }
+        
+        $this->_entry[$key] = $data;
+        $this->_expires[$key] = time() + $this->_life;
+        return true;
+    }
+    
+    /**
+     * 
+     * Inserts cache entry data, but only if the entry does not already exist.
+     * 
+     * @param string $key The entry ID.
+     * 
+     * @param mixed $data The data to write into the entry.
+     * 
+     * @return bool True on success, false on failure.
+     * 
+     */
+    public function add($key, $data)
+    {
+        if (! $this->_active) {
+            return;
+        }
+        
+        if (empty($this->_entry[$key])) {
+            return $this->save($key, $data);
+        } else {
+            return false;
+        }
+    }
+    
+    /**
+     * 
+     * Gets cache entry data.
+     * 
+     * @param string $key The entry ID.
+     * 
+     * @return mixed Boolean false on failure, cache data on success.
+     * 
+     */
+    public function fetch($key)
+    {
+        if (! $this->_active) {
+            return;
+        }
+        
+        if (! empty($this->_entry[$key]) && $this->_expires[$key] <= time()) {
+            // exists, and is within its lifetime
+            return $this->_entry[$key];
+        } else {
+            // clear the entry
+            unset($this->_entry[$key]);
+            unset($this->_expires[$key]);
+            return false;
+        }
+    }
+    
+    /**
+     * 
+     * Deletes a cache entry.
+     * 
+     * @param string $key The entry ID.
+     * 
+     * @return void
+     * 
+     */
+    public function delete($key)
+    {
+        if (! $this->_active) {
+            return;
+        }
+        
+        unset($this->_entry[$key]);
+        unset($this->_expires[$key]);
+    }
+    
+    /**
+     * 
+     * Removes all cache entries.
+     * 
+     * Note that APC makes a distinction between "user" entries and
+     * "system" entries; this only deletes the "user" entries.
+     * 
+     * @return void
+     * 
+     */
+    public function deleteAll()
+    {
+        if (! $this->_active) {
+            return;
+        }
+        
+        $this->_entry = array();
+        $this->_expires = array();
+    }
+    
+    /**
+     * 
+     * Returns the name for the entry key.
+     * 
+     * @param string $key The entry ID.
+     * 
+     * @return string The cache entry name.
+     * 
+     */
+    public function entry($key)
+    {
+        return $key;
+    }
+}