1: <?php
  2: /**
  3:  * CDirectoryCacheDependency class file.
  4:  *
  5:  * @author Qiang Xue <qiang.xue@gmail.com>
  6:  * @link http://www.yiiframework.com/
  7:  * @copyright 2008-2013 Yii Software LLC
  8:  * @license http://www.yiiframework.com/license/
  9:  */
 10: 
 11: /**
 12:  * CDirectoryCacheDependency represents a dependency based on change of a directory.
 13:  *
 14:  * CDirectoryCacheDependency performs dependency checking based on the
 15:  * modification time of the files contained in the specified directory.
 16:  * The directory being checked is specified via {@link directory}.
 17:  *
 18:  * By default, all files under the specified directory and subdirectories
 19:  * will be checked. If the last modification time of any of them is changed
 20:  * or if different number of files are contained in a directory, the dependency
 21:  * is reported as changed. By specifying {@link recursiveLevel},
 22:  * one can limit the checking to a certain depth of the directory.
 23:  *
 24:  * Note, dependency checking for a directory is expensive because it involves
 25:  * accessing modification time of multiple files under the directory.
 26:  *
 27:  * @author Qiang Xue <qiang.xue@gmail.com>
 28:  * @package system.caching.dependencies
 29:  * @since 1.0
 30:  */
 31: class CDirectoryCacheDependency extends CCacheDependency
 32: {
 33:     /**
 34:      * @var string the directory whose change is used to determine if the dependency has been changed.
 35:      * If any of the files under the directory is changed, the dependency is considered as changed.
 36:      */
 37:     public $directory;
 38:     /**
 39:      * @var integer the depth of the subdirectories to be recursively checked.
 40:      * If the value is less than 0, it means unlimited depth.
 41:      * If the value is 0, it means checking the files directly under the specified directory.
 42:      */
 43:     public $recursiveLevel=-1;
 44:     /**
 45:      * @var string the regular expression matching valid file/directory names.
 46:      * Only the matching files or directories will be checked for changes.
 47:      * Defaults to null, meaning all files/directories will qualify.
 48:      */
 49:     public $namePattern;
 50: 
 51:     /**
 52:      * Constructor.
 53:      * @param string $directory the directory to be checked
 54:      */
 55:     public function __construct($directory=null)
 56:     {
 57:         $this->directory=$directory;
 58:     }
 59: 
 60:     /**
 61:      * Generates the data needed to determine if dependency has been changed.
 62:      * This method returns the modification timestamps for files under the directory.
 63:      * @throws CException if {@link directory} is empty
 64:      * @return mixed the data needed to determine if dependency has been changed.
 65:      */
 66:     protected function generateDependentData()
 67:     {
 68:         if($this->directory!==null)
 69:             return $this->generateTimestamps($this->directory);
 70:         else
 71:             throw new CException(Yii::t('yii','CDirectoryCacheDependency.directory cannot be empty.'));
 72:     }
 73: 
 74:     /**
 75:      * Determines the last modification time for files under the directory.
 76:      * This method may go recursively into subdirectories if {@link recursiveLevel} is not 0.
 77:      * @param string $directory the directory name
 78:      * @param integer $level level of the recursion
 79:      * @throws CException if given directory is not valid
 80:      * @return array list of file modification time indexed by the file path
 81:      */
 82:     protected function generateTimestamps($directory,$level=0)
 83:     {
 84:         if(($dir=@opendir($directory))===false)
 85:             throw new CException(Yii::t('yii','"{path}" is not a valid directory.',
 86:                 array('{path}'=>$directory)));
 87:         $timestamps=array();
 88:         while(($file=readdir($dir))!==false)
 89:         {
 90:             $path=$directory.DIRECTORY_SEPARATOR.$file;
 91:             if($file==='.' || $file==='..')
 92:                 continue;
 93:             if($this->namePattern!==null && !preg_match($this->namePattern,$file))
 94:                 continue;
 95:             if(is_file($path))
 96:             {
 97:                 if($this->validateFile($path))
 98:                     $timestamps[$path]=filemtime($path);
 99:             }
100:             else
101:             {
102:                 if(($this->recursiveLevel<0 || $level<$this->recursiveLevel) && $this->validateDirectory($path))
103:                     $timestamps=array_merge($timestamps, $this->generateTimestamps($path,$level+1));
104:             }
105:         }
106:         closedir($dir);
107:         return $timestamps;
108:     }
109: 
110:     /**
111:      * Checks to see if the file should be checked for dependency.
112:      * This method is invoked when dependency of the whole directory is being checked.
113:      * By default, it always returns true, meaning the file should be checked.
114:      * You may override this method to check only certain files.
115:      * @param string $fileName the name of the file that may be checked for dependency.
116:      * @return boolean whether this file should be checked.
117:      */
118:     protected function validateFile($fileName)
119:     {
120:         return true;
121:     }
122: 
123:     /**
124:      * Checks to see if the specified subdirectory should be checked for dependency.
125:      * This method is invoked when dependency of the whole directory is being checked.
126:      * By default, it always returns true, meaning the subdirectory should be checked.
127:      * You may override this method to check only certain subdirectories.
128:      * @param string $directory the name of the subdirectory that may be checked for dependency.
129:      * @return boolean whether this subdirectory should be checked.
130:      */
131:     protected function validateDirectory($directory)
132:     {
133:         return true;
134:     }
135: }
136: