added cache dependency classes.

1 files changed, 438 insertions, 1 deletions

diff --git a/framework/Caching/TCache.php b/framework/Caching/TCache.php
index d974fe83..ca7348d4 100644
--- a/framework/Caching/TCache.php
+++ b/framework/Caching/TCache.php
@@ -1,6 +1,6 @@
 <?php

 /**

- * TCache class file.

+ * TCache and cache dependency classes.

  *

  * @author Qiang Xue <qiang.xue@gmail.com>

  * @link http://www.pradosoft.com/

@@ -10,6 +10,8 @@
  * @package System.Caching

  */

 

+Prado::using('System.Collections.TList');

+

 /**

  * TCache class

  *

@@ -229,4 +231,439 @@ abstract class TCache extends TModule implements ICache
 	abstract protected function deleteValue($key);

 }

 

+

+/**

+ * TCacheDependency class.

+ *

+ * TCacheDependency is the base class implementing {@link ICacheDependency} interface.

+ * Descendant classes must implement {@link checkChanges()} to provide

+ * actual dependency checking logic.

+ *

+ * The property value of {@link getHasChanged HasChanged} tells whether

+ * the dependency is changed or not.

+ *

+ * You may disable the dependency checking by setting {@link setEnabled Enabled}

+ * to false.

+ *

+ * Note, since the dependency objects often need to be serialized so that

+ * they can persist across requests, you may need to implement __sleep() and

+ * __wakeup() if the dependency objects contain resource handles which are

+ * not serializable.

+ *

+ * Currently, the following dependency classes are provided in the PRADO release:

+ * - {@link TFileCacheDependency}: checks whether a file is changed or not

+ * - {@link TDirectoryCacheDependency}: checks whether a directory is changed or not

+ * - {@link TGlobalStateCacheDependency}: checks whether a global state is changed or not

+ * - {@link TChainedCacheDependency}: checks whether any of a list of dependencies is changed or not

+ *

+ * @author Qiang Xue <qiang.xue@gmail.com>

+ * @version $Id $

+ * @package System.Caching

+ * @since 3.1.0

+ */

+abstract class TCacheDependency extends TComponent implements ICacheDependency

+{

+	private $_enabled=true;

+

+	/**

+	 * @return boolean whether this dependency is enabled. Default value is true.

+	 */

+	public function getEnabled()

+	{

+		return $this->_enabled;

+	}

+

+	/**

+	 * Sets a value indicating whether this cache dependency is enabled or not.

+	 * Cache dependency checking is only performed when it is enabled.

+	 * @param boolean whether this dependency is to be enabled.

+	 */

+	public function setEnabled($value)

+	{

+		$this->_enabled=TPropertyValue::ensureBoolean($value);

+	}

+

+	/**

+	 * @return boolean whether the dependency is changed or not.

+	 * If the dependency checking is disabled, it always returns false.

+	 */

+	public function getHasChanged()

+	{

+		return $this->_enabled ? $this->checkChanges() : false;

+	}

+

+	/**

+	 * Performs the actual dependency checking.

+	 * This method must be implemented by child classes.

+	 * @return boolean whether the dependency is changed or not.

+	 */

+	abstract protected function checkChanges();

+}

+

+

+/**

+ * TFileCacheDependency class.

+ *

+ * TFileCacheDependency performs dependency checking based on the

+ * last modification time of the file specified via {@link setFileName FileName}.

+ * The dependency is reported as unchanged if and only if the file's

+ * last modification time remains unchanged.

+ *

+ * @author Qiang Xue <qiang.xue@gmail.com>

+ * @version $Id $

+ * @package System.Caching

+ * @since 3.1.0

+ */

+class TFileCacheDependency extends TCacheDependency

+{

+	private $_fileName;

+	private $_timestamp;

+

+	/**

+	 * Constructor.

+	 * @param string name of the file whose change is to be checked.

+	 */

+	public function __construct($fileName)

+	{

+		$this->setFileName($fileName);

+	}

+

+	/**

+	 * @return string the name of the file whose change is to be checked

+	 */

+	public function getFileName()

+	{

+		return $this->_fileName;

+	}

+

+	/**

+	 * @param string the name of the file whose change is to be checked

+	 */

+	public function setFileName($value)

+	{

+		$this->_fileName=$value;

+		$this->_timestamp=@filemtime($value);

+	}

+

+	/**

+	 * @return int the last modification time of the file

+	 */

+	public function getTimestamp()

+	{

+		return $this->_timestamp;

+	}

+

+	/**

+	 * Performs the actual dependency checking.

+	 * This method returns true if the last modification time of the file is changed.

+	 * @return boolean whether the dependency is changed or not.

+	 */

+	protected function checkChanges()

+	{

+		return @filemtime($this->_fileName)!==$this->_timestamp;

+	}

+}

+

+/**

+ * TDirectoryCacheDependency class.

+ *

+ * TDirectoryCacheDependency performs dependency checking based on the

+ * modification time of the files contained in the specified directory.

+ * The directory being checked is specified via {@link setDirectory Directory}.

+ *

+ * By default, all files under the specified directory and subdirectories

+ * will be checked. If the last modification time of any of them is changed

+ * or if different number of files are contained in a directory, the dependency

+ * is reported as changed. By specifying {@link setRecursiveCheck RecursiveCheck}

+ * and {@link setRecursiveLevel RecursiveLevel}, one can limit the checking

+ * to a certain depth of the subdirectories.

+ *

+ * @author Qiang Xue <qiang.xue@gmail.com>

+ * @version $Id $

+ * @package System.Caching

+ * @since 3.1.0

+ */

+class TDirectoryCacheDependency extends TCacheDependency

+{

+	private $_recursiveCheck=true;

+	private $_recursiveLevel=-1;

+	private $_timestamps;

+	private $_directory;

+

+	/**

+	 * Constructor.

+	 * @param string the directory to be checked

+	 */

+	public function __construct($directory)

+	{

+		$this->setDirectory($directory);

+	}

+

+	/**

+	 * @return string the directory to be checked

+	 */

+	public function getDirectory()

+	{

+		return $this->_directory;

+	}

+

+	/**

+	 * @param string the directory to be checked

+	 * @throws TInvalidDataValueException if the directory does not exist

+	 */

+	public function setDirectory($directory)

+	{

+		if(($path=realpath($directory))===false || !is_dir($path))

+			throw new TInvalidDataValueException('directorycachedependency_directory_invalid',$directory);

+		$this->_directory=$path;

+		$this->_timestamps=$this->generateTimestamps($path);

+	}

+

+	/**

+	 * @return boolean whether the subdirectories of the directory will also be checked.

+	 * It defaults to true.

+	 */

+	public function getRecursiveCheck()

+	{

+		return $this->_recursiveCheck;

+	}

+

+	/**

+	 * @param boolean whether the subdirectories of the directory will also be checked.

+	 */

+	public function setRecursiveCheck($value)

+	{

+		$this->_recursiveCheck=TPropertyValue::ensureBoolean($value);

+	}

+

+	/**

+	 * @return int the depth of the subdirectories to be checked.

+	 * It defaults to -1, meaning unlimited depth.

+	 */

+	public function getRecursiveLevel()

+	{

+		return $this->_recursiveLevel;

+	}

+

+	/**

+	 * Sets a value indicating the depth of the subdirectories to be checked.

+	 * This is meaningful only when {@link getRecursiveCheck RecursiveCheck}

+	 * is true.

+	 * @param int the depth of the subdirectories to be checked.

+	 * If the value is less than 0, it means unlimited depth.

+	 * If the value is 0, it means checking the files directly under the specified directory.

+	 */

+	public function setRecursiveLevel($value)

+	{

+		$this->_recursiveLevel=TPropertyValue::ensureInteger($value);

+	}

+

+	/**

+	 * Performs the actual dependency checking.

+	 * This method returns true if the directory is changed.

+	 * @return boolean whether the dependency is changed or not.

+	 */

+	protected function checkChanges()

+	{

+		return $this->generateTimestamps($this->_directory)!=$this->_timestamps;

+	}

+

+	/**

+	 * Checks to see if the file should be checked for dependency.

+	 * This method is invoked when dependency of the whole directory is being checked.

+	 * By default, it always returns true, meaning the file should be checked.

+	 * You may override this method to check only certain files.

+	 * @param string the name of the file that may be checked for dependency.

+	 * @return boolean whether this file should be checked.

+	 */

+	protected function validateFile($fileName)

+	{

+		return true;

+	}

+

+	/**

+	 * Checks to see if the specified subdirectory should be checked for dependency.

+	 * This method is invoked when dependency of the whole directory is being checked.

+	 * By default, it always returns true, meaning the subdirectory should be checked.

+	 * You may override this method to check only certain subdirectories.

+	 * @param string the name of the subdirectory that may be checked for dependency.

+	 * @return boolean whether this subdirectory should be checked.

+	 */

+	protected function validateDirectory($directory)

+	{

+		return true;

+	}

+

+	/**

+	 * Determines the last modification time for files under the directory.

+	 * This method may go recurisvely into subdirectories if

+	 * {@link setRecursiveCheck RecursiveCheck} is set true.

+	 * @param string the directory name

+	 * @param int level of the recursion

+	 * @return array list of file modification time indexed by the file path

+	 */

+	protected function generateTimestamps($directory,$level=0)

+	{

+		if(($dir=opendir($directory))===false)

+			throw new TIOException('directorycachedependency_directory_invalid',$directory);

+		$timestamps=array();

+		while(($file=readdir($dir))!==false)

+		{

+			$path=$directory.DIRECTORY_SEPARATOR.$file;

+			if($file==='.' || $file==='..')

+				continue;

+			else if(is_dir($path))

+			{

+				if(($this->_recursiveLevel<0 || $level<$this->_recursiveLevel) && $this->validateDirectory($path))

+					$timestamps=array_merge($this->generateTimestamps($path,$level+1));

+			}

+			else if($this->validateFile($path))

+				$timestamps[$path]=filemtime($path);

+		}

+		closedir($dir);

+		return $timestamps;

+	}

+}

+

+

+/**

+ * TGlobalStateCacheDependency class.

+ *

+ * TGlobalStateCacheDependency checks if a global state is changed or not.

+ * If the global state is changed, the dependency is reported as changed.

+ * To specify which global state this dependency should check with,

+ * set {@link setStateName StateName} to the name of the global state.

+ *

+ * @author Qiang Xue <qiang.xue@gmail.com>

+ * @version $Id $

+ * @package System.Caching

+ * @since 3.1.0

+ */

+class TGlobalStateCacheDependency extends TCacheDependency

+{

+	private $_stateName;

+	private $_stateValue;

+

+	/**

+	 * Constructor.

+	 * @param string the name of the global state

+	 */

+	public function __construct($name)

+	{

+		$this->setStateName($name);

+	}

+

+	/**

+	 * @return string the name of the global state

+	 */

+	public function getStateName()

+	{

+		return $this->_stateName;

+	}

+

+	/**

+	 * @param string the name of the global state

+	 * @see TApplication::setGlobalState

+	 */

+	public function setStateName($value)

+	{

+		$this->_stateName=$value;

+		$this->_stateValue=Prado::getApplication()->getGlobalState($value);

+	}

+

+	/**

+	 * Performs the actual dependency checking.

+	 * This method returns true if the specified global state is changed.

+	 * @return boolean whether the dependency is changed or not.

+	 */

+	protected function checkChanges()

+	{

+		return $this->_stateValue!==Prado::getApplication()->getGlobalState($value);

+	}

+}

+

+

+/**

+ * TChainedCacheDependency class.

+ *

+ * TChainedCacheDependency represents a list of cache dependency objects

+ * and performs the dependency checking based on the checking results of

+ * these objects. If any of them reports a dependency change, TChainedCacheDependency

+ * will return true for the checking.

+ *

+ * To add dependencies to TChainedCacheDependency, use {@link getDependencies Dependencies}

+ * which gives a {@link TCacheDependencyList} instance and can be used like an array

+ * (see {@link TList} for more details}).

+ *

+ * @author Qiang Xue <qiang.xue@gmail.com>

+ * @version $Id $

+ * @package System.Caching

+ * @since 3.1.0

+ */

+class TChainedCacheDependency extends TCacheDependency

+{

+	private $_dependencies=null;

+

+	/**

+	 * @return TCacheDependencyList list of dependency objects

+	 */

+	public function getDependencies()

+	{

+		if($this->_dependencies===null)

+			$this->_dependencies=new TCacheDependencyList;

+		return $this->_dependencies;

+	}

+

+	/**

+	 * Performs the actual dependency checking.

+	 * This method returns true if any of the dependency objects

+	 * reports a dependency change.

+	 * @return boolean whether the dependency is changed or not.

+	 */

+	protected function checkChanges()

+	{

+		if($this->_dependencies!==null)

+		{

+			foreach($this->_dependencies as $dependency)

+				if($dependency->getHasChanged())

+					return true;

+		}

+		return false;

+	}

+}

+

+

+/**

+ * TCacheDependencyList class.

+ *

+ * TCacheDependencyList represents a list of cache dependency objects.

+ * Only objects implementing {@link ICacheDependency} can be added into this list.

+ *

+ * TCacheDependencyList can be used like an array. See {@link TList}

+ * for more details.

+ *

+ * @author Qiang Xue <qiang.xue@gmail.com>

+ * @version $Id $

+ * @package System.Caching

+ * @since 3.1.0

+ */

+class TCacheDependencyList extends TList

+{

+	/**

+	 * Inserts an item at the specified position.

+	 * This overrides the parent implementation by performing additional type checking

+	 * for each newly added item.

+	 * @param integer the speicified position.

+	 * @param mixed new item

+	 * @throws TInvalidDataTypeException if the item to be inserted is not a dependency instance

+	 */

+	public function insertAt($index,$item)

+	{

+		if($item instanceof ICacheDependency)

+			parent::insertAt($index,$item);

+		else

+			throw new TInvalidDataTypeException('cachedependencylist_cachedependency_required');

+	}

+}

+

 ?>
\ No newline at end of file