[Sommaire] [Imprimer]

   1  <?php
   2  
   3  /**
   4  * This class extends Cache_Lite and offers a cache system driven by a master file
   5  *
   6  * With this class, cache validity is only dependent of a given file. Cache files
   7  * are valid only if they are older than the master file. It's a perfect way for
   8  * caching templates results (if the template file is newer than the cache, cache
   9  * must be rebuild...) or for config classes...
  10  * There are some examples in the 'docs/examples' file
  11  * Technical choices are described in the 'docs/technical' file
  12  *
  13  * @package Cache_Lite
  14  * @version $Id: File.php,v 1.3 2005/12/04 16:03:55 fab Exp $
  15  * @author Fabien MARTY <fab@php.net>
  16  */
  17   
  18  require_once ('Cache/Lite.php');
  19  
  20  class Cache_Lite_File extends Cache_Lite
  21  {
  22  
  23      // --- Private properties ---
  24      
  25      /**
  26      * Complete path of the file used for controlling the cache lifetime
  27      *
  28      * @var string $_masterFile
  29      */
  30      var $_masterFile = '';
  31      
  32      /**
  33      * Masterfile mtime
  34      *
  35      * @var int $_masterFile_mtime
  36      */
  37      var $_masterFile_mtime = 0;
  38      
  39      // --- Public methods ----
  40      
  41      /**
  42      * Constructor
  43      *
  44      * $options is an assoc. To have a look at availables options,
  45      * see the constructor of the Cache_Lite class in 'Cache_Lite.php'
  46      *
  47      * Comparing to Cache_Lite constructor, there is another option :
  48      * $options = array(
  49      *     (...) see Cache_Lite constructor
  50      *     'masterFile' => complete path of the file used for controlling the cache lifetime(string)
  51      * );
  52      *
  53      * @param array $options options
  54      * @access public
  55      */
  56      function Cache_Lite_File($options = array(NULL))
  57      {   
  58          $options['lifetime'] = 0;
  59          $this->Cache_Lite($options);
  60          if (isset($options['masterFile'])) {
  61              $this->_masterFile = $options['masterFile'];
  62          } else {
  63              return $this->raiseError('Cache_Lite_File : masterFile option must be set !');
  64          }
  65          if (!($this->_masterFile_mtime = @filemtime($this->_masterFile))) {
  66              return $this->raiseError('Cache_Lite_File : Unable to read masterFile : '.$this->_masterFile, -3);
  67          }
  68      }
  69      
  70      /**
  71      * Test if a cache is available and (if yes) return it
  72      *
  73      * @param string $id cache id
  74      * @param string $group name of the cache group
  75      * @return string data of the cache (or false if no cache available)
  76      * @access public
  77      */
  78      function get($id, $group = 'default') 
  79      {
  80          if ($data = parent::get($id, $group, true)) {
  81              if ($filemtime = $this->lastModified()) {
  82                  if ($filemtime > $this->_masterFile_mtime) {
  83                      return $data;
  84                  }
  85              }
  86          }
  87          return false;
  88      }
  89  
  90  }
  91  
  92  ?>