includes/objectcache/MemcachedBagOStuff.php

   1 <?php
   2 /**
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2 of the License, or
   6  * (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along
  14  * with this program; if not, write to the Free Software Foundation, Inc.,
  15  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  16  * http://www.gnu.org/copyleft/gpl.html
  17  *
  18  * @file
  19  * @ingroup Cache
  20  */
  21
  22 /**
  23  * Base class for memcached clients.
  24  *
  25  * @ingroup Cache
  26  */
  27 class MemcachedBagOStuff extends BagOStuff {
  28         protected $client;
  29
  30         /**
  31          * Fill in the defaults for any parameters missing from $params, using the
  32          * backwards-compatible global variables
  33          */
  34         protected function applyDefaultParams( $params ) {
  35                 if ( !isset( $params['servers'] ) ) {
  36                         $params['servers'] = $GLOBALS['wgMemCachedServers'];
  37                 }
  38                 if ( !isset( $params['debug'] ) ) {
  39                         $params['debug'] = $GLOBALS['wgMemCachedDebug'];
  40                 }
  41                 if ( !isset( $params['persistent'] ) ) {
  42                         $params['persistent'] = $GLOBALS['wgMemCachedPersistent'];
  43                 }
  44                 if  ( !isset( $params['compress_threshold'] ) ) {
  45                         $params['compress_threshold'] = 1500;
  46                 }
  47                 if ( !isset( $params['timeout'] ) ) {
  48                         $params['timeout'] = $GLOBALS['wgMemCachedTimeout'];
  49                 }
  50                 if ( !isset( $params['connect_timeout'] ) ) {
  51                         $params['connect_timeout'] = 0.1;
  52                 }
  53                 return $params;
  54         }
  55
  56         /**
  57          * @param $key string
  58          * @return Mixed
  59          */
  60         public function get( $key ) {
  61                 return $this->client->get( $this->encodeKey( $key ) );
  62         }
  63
  64         /**
  65          * @param $key string
  66          * @param $value
  67          * @param $exptime int
  68          * @return bool
  69          */
  70         public function set( $key, $value, $exptime = 0 ) {
  71                 return $this->client->set( $this->encodeKey( $key ), $value,
  72                         $this->fixExpiry( $exptime ) );
  73         }
  74
  75         /**
  76          * @param $key string
  77          * @param $time int
  78          * @return bool
  79          */
  80         public function delete( $key, $time = 0 ) {
  81                 return $this->client->delete( $this->encodeKey( $key ), $time );
  82         }
  83
  84         /**
  85          * @param $key string
  86          * @param $value int
  87          * @return Mixed
  88          */
  89         public function add( $key, $value, $exptime = 0 ) {
  90                 return $this->client->add( $this->encodeKey( $key ), $value,
  91                         $this->fixExpiry( $exptime ) );
  92         }
  93
  94         /**
  95          * @param $key string
  96          * @param $value int
  97          * @param $exptime
  98          * @return Mixed
  99          */
 100         public function replace( $key, $value, $exptime = 0 ) {
 101                 return $this->client->replace( $this->encodeKey( $key ), $value,
 102                         $this->fixExpiry( $exptime ) );
 103         }
 104
 105         /**
 106          * Get the underlying client object. This is provided for debugging
 107          * purposes.
 108          */
 109         public function getClient() {
 110                 return $this->client;
 111         }
 112
 113         /**
 114          * Encode a key for use on the wire inside the memcached protocol.
 115          *
 116          * We encode spaces and line breaks to avoid protocol errors. We encode
 117          * the other control characters for compatibility with libmemcached
 118          * verify_key. We leave other punctuation alone, to maximise backwards
 119          * compatibility.
 120          * @return string
 121          */
 122         public function encodeKey( $key ) {
 123                 return preg_replace_callback( '/[\x00-\x20\x25\x7f]+/',
 124                         array( $this, 'encodeKeyCallback' ), $key );
 125         }
 126
 127         protected function encodeKeyCallback( $m ) {
 128                 return rawurlencode( $m[0] );
 129         }
 130
 131         /**
 132          * TTLs higher than 30 days will be detected as absolute TTLs
 133          * (UNIX timestamps), and will result in the cache entry being
 134          * discarded immediately because the expiry is in the past.
 135          * Clamp expiries >30d at 30d, unless they're >=1e9 in which
 136          * case they are likely to really be absolute (1e9 = 2011-09-09)
 137          */
 138         function fixExpiry( $expiry ) {
 139                 if ( $expiry > 2592000 && $expiry < 1000000000 ) {
 140                         $expiry = 2592000;
 141                 }
 142                 return $expiry;
 143         }
 144
 145         /**
 146          * Decode a key encoded with encodeKey(). This is provided as a convenience
 147          * function for debugging.
 148          *
 149          * @param $key string
 150          *
 151          * @return string
 152          */
 153         public function decodeKey( $key ) {
 154                 return urldecode( $key );
 155         }
 156
 157         /**
 158          * Send a debug message to the log
 159          */
 160         protected function debugLog( $text ) {
 161                 global $wgDebugLogGroups;
 162                 if( !isset( $wgDebugLogGroups['memcached'] ) ) {
 163                         # Prefix message since it will end up in main debug log file
 164                         $text = "memcached: $text";
 165                 }
 166                 if ( substr( $text, -1 ) !== "\n" ) {
 167                         $text .= "\n";
 168                 }
 169                 wfDebugLog( 'memcached', $text );
 170         }
 171 }
 172