1 <?php

     2 /**

     3  * Zend Framework

     4  *

     5  * LICENSE

     6  *

     7  * This source file is subject to the new BSD license that is bundled

     8  * with this package in the file LICENSE.txt.

     9  * It is also available through the world-wide-web at this URL:

    10  * http://framework.zend.com/license/new-bsd

    11  * If you did not receive a copy of the license and are unable to

    12  * obtain it through the world-wide-web, please send an email

    13  * to license@zend.com so we can send you a copy immediately.

    14  *

    15  * @category   Zend

    16  * @package    Zend_Cache

    17  * @subpackage Zend_Cache_Backend

    18  * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

    19  * @license    http://framework.zend.com/license/new-bsd     New BSD License

    20  * @version    $Id: Memcached.php 22207 2010-05-20 16:47:16Z mabe $

    21  */

    22 

    23 

    24 /**

    25  * @see Zend_Cache_Backend_Interface

    26  */

    27 require_once 'Zend/Cache/Backend/ExtendedInterface.php';

    28 

    29 /**

    30  * @see Zend_Cache_Backend

    31  */

    32 require_once 'Zend/Cache/Backend.php';

    33 

    34 

    35 /**

    36  * @package    Zend_Cache

    37  * @subpackage Zend_Cache_Backend

    38  * @copyright  Copyright (c) 2005-2010 Zend Technologies USA Inc. (http://www.zend.com)

    39  * @license    http://framework.zend.com/license/new-bsd     New BSD License

    40  */

    41 class Zend_Cache_Backend_Memcached extends Zend_Cache_Backend implements Zend_Cache_Backend_ExtendedInterface

    42 {

    43     /**

    44      * Default Values

    45      */

    46     const DEFAULT_HOST = '127.0.0.1';

    47     const DEFAULT_PORT =  11211;

    48     const DEFAULT_PERSISTENT = true;

    49     const DEFAULT_WEIGHT  = 1;

    50     const DEFAULT_TIMEOUT = 1;

    51     const DEFAULT_RETRY_INTERVAL = 15;

    52     const DEFAULT_STATUS = true;

    53     const DEFAULT_FAILURE_CALLBACK = null;

    54 

    55     /**

    56      * Log message

    57      */

    58     const TAGS_UNSUPPORTED_BY_CLEAN_OF_MEMCACHED_BACKEND = 'Zend_Cache_Backend_Memcached::clean() : tags are unsupported by the Memcached backend';

    59     const TAGS_UNSUPPORTED_BY_SAVE_OF_MEMCACHED_BACKEND =  'Zend_Cache_Backend_Memcached::save() : tags are unsupported by the Memcached backend';

    60 

    61     /**

    62      * Available options

    63      *

    64      * =====> (array) servers :

    65      * an array of memcached server ; each memcached server is described by an associative array :

    66      * 'host' => (string) : the name of the memcached server

    67      * 'port' => (int) : the port of the memcached server

    68      * 'persistent' => (bool) : use or not persistent connections to this memcached server

    69      * 'weight' => (int) : number of buckets to create for this server which in turn control its

    70      *                     probability of it being selected. The probability is relative to the total

    71      *                     weight of all servers.

    72      * 'timeout' => (int) : value in seconds which will be used for connecting to the daemon. Think twice

    73      *                      before changing the default value of 1 second - you can lose all the

    74      *                      advantages of caching if your connection is too slow.

    75      * 'retry_interval' => (int) : controls how often a failed server will be retried, the default value

    76      *                             is 15 seconds. Setting this parameter to -1 disables automatic retry.

    77      * 'status' => (bool) : controls if the server should be flagged as online.

    78      * 'failure_callback' => (callback) : Allows the user to specify a callback function to run upon

    79      *                                    encountering an error. The callback is run before failover

    80      *                                    is attempted. The function takes two parameters, the hostname

    81      *                                    and port of the failed server.

    82      *

    83      * =====> (boolean) compression :

    84      * true if you want to use on-the-fly compression

    85      *

    86      * =====> (boolean) compatibility :

    87      * true if you use old memcache server or extension

    88      *

    89      * @var array available options

    90      */

    91     protected $_options = array(

    92         'servers' => array(array(

    93             'host' => self::DEFAULT_HOST,

    94             'port' => self::DEFAULT_PORT,

    95             'persistent' => self::DEFAULT_PERSISTENT,

    96             'weight'  => self::DEFAULT_WEIGHT,

    97             'timeout' => self::DEFAULT_TIMEOUT,

    98             'retry_interval' => self::DEFAULT_RETRY_INTERVAL,

    99             'status' => self::DEFAULT_STATUS,

   100             'failure_callback' => self::DEFAULT_FAILURE_CALLBACK

   101         )),

   102         'compression' => false,

   103         'compatibility' => false,

   104     );

   105 

   106     /**

   107      * Memcache object

   108      *

   109      * @var mixed memcache object

   110      */

   111     protected $_memcache = null;

   112 

   113     /**

   114      * Constructor

   115      *

   116      * @param array $options associative array of options

   117      * @throws Zend_Cache_Exception

   118      * @return void

   119      */

   120     public function __construct(array $options = array())

   121     {

   122         if (!extension_loaded('memcache')) {

   123             Zend_Cache::throwException('The memcache extension must be loaded for using this backend !');

   124         }

   125         parent::__construct($options);

   126         if (isset($this->_options['servers'])) {

   127             $value= $this->_options['servers'];

   128             if (isset($value['host'])) {

   129                 // in this case, $value seems to be a simple associative array (one server only)

   130                 $value = array(0 => $value); // let's transform it into a classical array of associative arrays

   131             }

   132             $this->setOption('servers', $value);

   133         }

   134         $this->_memcache = new Memcache;

   135         foreach ($this->_options['servers'] as $server) {

   136             if (!array_key_exists('port', $server)) {

   137                 $server['port'] = self::DEFAULT_PORT;

   138             }

   139             if (!array_key_exists('persistent', $server)) {

   140                 $server['persistent'] = self::DEFAULT_PERSISTENT;

   141             }

   142             if (!array_key_exists('weight', $server)) {

   143                 $server['weight'] = self::DEFAULT_WEIGHT;

   144             }

   145             if (!array_key_exists('timeout', $server)) {

   146                 $server['timeout'] = self::DEFAULT_TIMEOUT;

   147             }

   148             if (!array_key_exists('retry_interval', $server)) {

   149                 $server['retry_interval'] = self::DEFAULT_RETRY_INTERVAL;

   150             }

   151             if (!array_key_exists('status', $server)) {

   152                 $server['status'] = self::DEFAULT_STATUS;

   153             }

   154             if (!array_key_exists('failure_callback', $server)) {

   155                 $server['failure_callback'] = self::DEFAULT_FAILURE_CALLBACK;

   156             }

   157             if ($this->_options['compatibility']) {

   158                 // No status for compatibility mode (#ZF-5887)

   159                 $this->_memcache->addServer($server['host'], $server['port'], $server['persistent'],

   160                                         $server['weight'], $server['timeout'],

   161                                         $server['retry_interval']);

   162             } else {

   163                 $this->_memcache->addServer($server['host'], $server['port'], $server['persistent'],

   164                                         $server['weight'], $server['timeout'],

   165                                         $server['retry_interval'],

   166                                         $server['status'], $server['failure_callback']);

   167             }

   168         }

   169     }

   170 

   171     /**

   172      * Test if a cache is available for the given id and (if yes) return it (false else)

   173      *

   174      * @param  string  $id                     Cache id

   175      * @param  boolean $doNotTestCacheValidity If set to true, the cache validity won't be tested

   176      * @return string|false cached datas

   177      */

   178     public function load($id, $doNotTestCacheValidity = false)

   179     {

   180         $tmp = $this->_memcache->get($id);

   181         if (is_array($tmp) && isset($tmp[0])) {

   182             return $tmp[0];

   183         }

   184         return false;

   185     }

   186 

   187     /**

   188      * Test if a cache is available or not (for the given id)

   189      *

   190      * @param  string $id Cache id

   191      * @return mixed|false (a cache is not available) or "last modified" timestamp (int) of the available cache record

   192      */

   193     public function test($id)

   194     {

   195         $tmp = $this->_memcache->get($id);

   196         if (is_array($tmp)) {

   197             return $tmp[1];

   198         }

   199         return false;

   200     }

   201 

   202     /**

   203      * Save some string datas into a cache record

   204      *

   205      * Note : $data is always "string" (serialization is done by the

   206      * core not by the backend)

   207      *

   208      * @param  string $data             Datas to cache

   209      * @param  string $id               Cache id

   210      * @param  array  $tags             Array of strings, the cache record will be tagged by each string entry

   211      * @param  int    $specificLifetime If != false, set a specific lifetime for this cache record (null => infinite lifetime)

   212      * @return boolean True if no problem

   213      */

   214     public function save($data, $id, $tags = array(), $specificLifetime = false)

   215     {

   216         $lifetime = $this->getLifetime($specificLifetime);

   217         if ($this->_options['compression']) {

   218             $flag = MEMCACHE_COMPRESSED;

   219         } else {

   220             $flag = 0;

   221         }

   222 

   223         // ZF-8856: using set because add needs a second request if item already exists

   224         $result = @$this->_memcache->set($id, array($data, time(), $lifetime), $flag, $lifetime);

   225 

   226         if (count($tags) > 0) {

   227             $this->_log(self::TAGS_UNSUPPORTED_BY_SAVE_OF_MEMCACHED_BACKEND);

   228         }

   229 

   230         return $result;

   231     }

   232 

   233     /**

   234      * Remove a cache record

   235      *

   236      * @param  string $id Cache id

   237      * @return boolean True if no problem

   238      */

   239     public function remove($id)

   240     {

   241         return $this->_memcache->delete($id, 0);

   242     }

   243 

   244     /**

   245      * Clean some cache records

   246      *

   247      * Available modes are :

   248      * 'all' (default)  => remove all cache entries ($tags is not used)

   249      * 'old'            => unsupported

   250      * 'matchingTag'    => unsupported

   251      * 'notMatchingTag' => unsupported

   252      * 'matchingAnyTag' => unsupported

   253      *

   254      * @param  string $mode Clean mode

   255      * @param  array  $tags Array of tags

   256      * @throws Zend_Cache_Exception

   257      * @return boolean True if no problem

   258      */

   259     public function clean($mode = Zend_Cache::CLEANING_MODE_ALL, $tags = array())

   260     {

   261         switch ($mode) {

   262             case Zend_Cache::CLEANING_MODE_ALL:

   263                 return $this->_memcache->flush();

   264                 break;

   265             case Zend_Cache::CLEANING_MODE_OLD:

   266                 $this->_log("Zend_Cache_Backend_Memcached::clean() : CLEANING_MODE_OLD is unsupported by the Memcached backend");

   267                 break;

   268             case Zend_Cache::CLEANING_MODE_MATCHING_TAG:

   269             case Zend_Cache::CLEANING_MODE_NOT_MATCHING_TAG:

   270             case Zend_Cache::CLEANING_MODE_MATCHING_ANY_TAG:

   271                 $this->_log(self::TAGS_UNSUPPORTED_BY_CLEAN_OF_MEMCACHED_BACKEND);

   272                 break;

   273                default:

   274                 Zend_Cache::throwException('Invalid mode for clean() method');

   275                    break;

   276         }

   277     }

   278 

   279     /**

   280      * Return true if the automatic cleaning is available for the backend

   281      *

   282      * @return boolean

   283      */

   284     public function isAutomaticCleaningAvailable()

   285     {

   286         return false;

   287     }

   288 

   289     /**

   290      * Set the frontend directives

   291      *

   292      * @param  array $directives Assoc of directives

   293      * @throws Zend_Cache_Exception

   294      * @return void

   295      */

   296     public function setDirectives($directives)

   297     {

   298         parent::setDirectives($directives);

   299         $lifetime = $this->getLifetime(false);

   300         if ($lifetime > 2592000) {

   301             // #ZF-3490 : For the memcached backend, there is a lifetime limit of 30 days (2592000 seconds)

   302             $this->_log('memcached backend has a limit of 30 days (2592000 seconds) for the lifetime');

   303         }

   304         if ($lifetime === null) {

   305             // #ZF-4614 : we tranform null to zero to get the maximal lifetime

   306             parent::setDirectives(array('lifetime' => 0));

   307         }

   308     }

   309 

   310     /**

   311      * Return an array of stored cache ids

   312      *

   313      * @return array array of stored cache ids (string)

   314      */

   315     public function getIds()

   316     {

   317         $this->_log("Zend_Cache_Backend_Memcached::save() : getting the list of cache ids is unsupported by the Memcache backend");

   318         return array();

   319     }

   320 

   321     /**

   322      * Return an array of stored tags

   323      *

   324      * @return array array of stored tags (string)

   325      */

   326     public function getTags()

   327     {

   328         $this->_log(self::TAGS_UNSUPPORTED_BY_SAVE_OF_MEMCACHED_BACKEND);

   329         return array();

   330     }

   331 

   332     /**

   333      * Return an array of stored cache ids which match given tags

   334      *

   335      * In case of multiple tags, a logical AND is made between tags

   336      *

   337      * @param array $tags array of tags

   338      * @return array array of matching cache ids (string)

   339      */

   340     public function getIdsMatchingTags($tags = array())

   341     {

   342         $this->_log(self::TAGS_UNSUPPORTED_BY_SAVE_OF_MEMCACHED_BACKEND);

   343         return array();

   344     }

   345 

   346     /**

   347      * Return an array of stored cache ids which don't match given tags

   348      *

   349      * In case of multiple tags, a logical OR is made between tags

   350      *

   351      * @param array $tags array of tags

   352      * @return array array of not matching cache ids (string)

   353      */

   354     public function getIdsNotMatchingTags($tags = array())

   355     {

   356         $this->_log(self::TAGS_UNSUPPORTED_BY_SAVE_OF_MEMCACHED_BACKEND);

   357         return array();

   358     }

   359 

   360     /**

   361      * Return an array of stored cache ids which match any given tags

   362      *

   363      * In case of multiple tags, a logical AND is made between tags

   364      *

   365      * @param array $tags array of tags

   366      * @return array array of any matching cache ids (string)

   367      */

   368     public function getIdsMatchingAnyTags($tags = array())

   369     {

   370         $this->_log(self::TAGS_UNSUPPORTED_BY_SAVE_OF_MEMCACHED_BACKEND);

   371         return array();

   372     }

   373 

   374     /**

   375      * Return the filling percentage of the backend storage

   376      *

   377      * @throws Zend_Cache_Exception

   378      * @return int integer between 0 and 100

   379      */

   380     public function getFillingPercentage()

   381     {

   382         $mems = $this->_memcache->getExtendedStats();

   383 

   384         $memSize = null;

   385         $memUsed = null;

   386         foreach ($mems as $key => $mem) {

   387             if ($mem === false) {

   388                 $this->_log('can\'t get stat from ' . $key);

   389                 continue;

   390             }

   391 

   392             $eachSize = $mem['limit_maxbytes'];

   393             $eachUsed = $mem['bytes'];

   394             if ($eachUsed > $eachSize) {

   395                 $eachUsed = $eachSize;

   396             }

   397 

   398             $memSize += $eachSize;

   399             $memUsed += $eachUsed;

   400         }

   401 

   402         if ($memSize === null || $memUsed === null) {

   403             Zend_Cache::throwException('Can\'t get filling percentage');

   404         }

   405 

   406         return ((int) (100. * ($memUsed / $memSize)));

   407     }

   408 

   409     /**

   410      * Return an array of metadatas for the given cache id

   411      *

   412      * The array must include these keys :

   413      * - expire : the expire timestamp

   414      * - tags : a string array of tags

   415      * - mtime : timestamp of last modification time

   416      *

   417      * @param string $id cache id

   418      * @return array array of metadatas (false if the cache id is not found)

   419      */

   420     public function getMetadatas($id)

   421     {

   422         $tmp = $this->_memcache->get($id);

   423         if (is_array($tmp)) {

   424             $data = $tmp[0];

   425             $mtime = $tmp[1];

   426             if (!isset($tmp[2])) {

   427                 // because this record is only with 1.7 release

   428                 // if old cache records are still there...

   429                 return false;

   430             }

   431             $lifetime = $tmp[2];

   432             return array(

   433                 'expire' => $mtime + $lifetime,

   434                 'tags' => array(),

   435                 'mtime' => $mtime

   436             );

   437         }

   438         return false;

   439     }

   440 

   441     /**

   442      * Give (if possible) an extra lifetime to the given cache id

   443      *

   444      * @param string $id cache id

   445      * @param int $extraLifetime

   446      * @return boolean true if ok

   447      */

   448     public function touch($id, $extraLifetime)

   449     {

   450         if ($this->_options['compression']) {

   451             $flag = MEMCACHE_COMPRESSED;

   452         } else {

   453             $flag = 0;

   454         }

   455         $tmp = $this->_memcache->get($id);

   456         if (is_array($tmp)) {

   457             $data = $tmp[0];

   458             $mtime = $tmp[1];

   459             if (!isset($tmp[2])) {

   460                 // because this record is only with 1.7 release

   461                 // if old cache records are still there...

   462                 return false;

   463             }

   464             $lifetime = $tmp[2];

   465             $newLifetime = $lifetime - (time() - $mtime) + $extraLifetime;

   466             if ($newLifetime <=0) {

   467                 return false;

   468             }

   469             // #ZF-5702 : we try replace() first becase set() seems to be slower

   470             if (!($result = $this->_memcache->replace($id, array($data, time(), $newLifetime), $flag, $newLifetime))) {

   471                 $result = $this->_memcache->set($id, array($data, time(), $newLifetime), $flag, $newLifetime);

   472             }

   473             return $result;

   474         }

   475         return false;

   476     }

   477 

   478     /**

   479      * Return an associative array of capabilities (booleans) of the backend

   480      *

   481      * The array must include these keys :

   482      * - automatic_cleaning (is automating cleaning necessary)

   483      * - tags (are tags supported)

   484      * - expired_read (is it possible to read expired cache records

   485      *                 (for doNotTestCacheValidity option for example))

   486      * - priority does the backend deal with priority when saving

   487      * - infinite_lifetime (is infinite lifetime can work with this backend)

   488      * - get_list (is it possible to get the list of cache ids and the complete list of tags)

   489      *

   490      * @return array associative of with capabilities

   491      */

   492     public function getCapabilities()

   493     {

   494         return array(

   495             'automatic_cleaning' => false,

   496             'tags' => false,

   497             'expired_read' => false,

   498             'priority' => false,

   499             'infinite_lifetime' => false,

   500             'get_list' => false

   501         );

   502     }

   503 

   504 }