includes/libs/objectcache/MemcachedPeclBagOStuff.php

   1 <?php
   2 /**
   3  * Object caching using memcached.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Cache
  22  */
  23
  24 /**
  25  * A wrapper class for the PECL memcached client
  26  *
  27  * @ingroup Cache
  28  */
  29 class MemcachedPeclBagOStuff extends MemcachedBagOStuff {
  30
  31         /**
  32          * Available parameters are:
  33          *   - servers:             The list of IP:port combinations holding the memcached servers.
  34          *   - persistent:          Whether to use a persistent connection
  35          *   - compress_threshold:  The minimum size an object must be before it is compressed
  36          *   - timeout:             The read timeout in microseconds
  37          *   - connect_timeout:     The connect timeout in seconds
  38          *   - retry_timeout:       Time in seconds to wait before retrying a failed connect attempt
  39          *   - server_failure_limit:  Limit for server connect failures before it is removed
  40          *   - serializer:          May be either "php" or "igbinary". Igbinary produces more compact
  41          *                          values, but serialization is much slower unless the php.ini option
  42          *                          igbinary.compact_strings is off.
  43          *   - use_binary_protocol  Whether to enable the binary protocol (default is ASCII) (boolean)
  44          * @param array $params
  45          * @throws InvalidArgumentException
  46          */
  47         function __construct( $params ) {
  48                 parent::__construct( $params );
  49                 $params = $this->applyDefaultParams( $params );
  50
  51                 if ( $params['persistent'] ) {
  52                         // The pool ID must be unique to the server/option combination.
  53                         // The Memcached object is essentially shared for each pool ID.
  54                         // We can only reuse a pool ID if we keep the config consistent.
  55                         $this->client = new Memcached( md5( serialize( $params ) ) );
  56                         if ( count( $this->client->getServerList() ) ) {
  57                                 $this->logger->debug( __METHOD__ . ": persistent Memcached object already loaded." );
  58                                 return; // already initialized; don't add duplicate servers
  59                         }
  60                 } else {
  61                         $this->client = new Memcached;
  62                 }
  63
  64                 if ( $params['use_binary_protocol'] ) {
  65                         $this->client->setOption( Memcached::OPT_BINARY_PROTOCOL, true );
  66                 }
  67
  68                 if ( isset( $params['retry_timeout'] ) ) {
  69                         $this->client->setOption( Memcached::OPT_RETRY_TIMEOUT, $params['retry_timeout'] );
  70                 }
  71
  72                 if ( isset( $params['server_failure_limit'] ) ) {
  73                         $this->client->setOption( Memcached::OPT_SERVER_FAILURE_LIMIT, $params['server_failure_limit'] );
  74                 }
  75
  76                 // The compression threshold is an undocumented php.ini option for some
  77                 // reason. There's probably not much harm in setting it globally, for
  78                 // compatibility with the settings for the PHP client.
  79                 ini_set( 'memcached.compression_threshold', $params['compress_threshold'] );
  80
  81                 // Set timeouts
  82                 $this->client->setOption( Memcached::OPT_CONNECT_TIMEOUT, $params['connect_timeout'] * 1000 );
  83                 $this->client->setOption( Memcached::OPT_SEND_TIMEOUT, $params['timeout'] );
  84                 $this->client->setOption( Memcached::OPT_RECV_TIMEOUT, $params['timeout'] );
  85                 $this->client->setOption( Memcached::OPT_POLL_TIMEOUT, $params['timeout'] / 1000 );
  86
  87                 // Set libketama mode since it's recommended by the documentation and
  88                 // is as good as any. There's no way to configure libmemcached to use
  89                 // hashes identical to the ones currently in use by the PHP client, and
  90                 // even implementing one of the libmemcached hashes in pure PHP for
  91                 // forwards compatibility would require MemcachedClient::get_sock() to be
  92                 // rewritten.
  93                 $this->client->setOption( Memcached::OPT_LIBKETAMA_COMPATIBLE, true );
  94
  95                 // Set the serializer
  96                 switch ( $params['serializer'] ) {
  97                         case 'php':
  98                                 $this->client->setOption( Memcached::OPT_SERIALIZER, Memcached::SERIALIZER_PHP );
  99                                 break;
 100                         case 'igbinary':
 101                                 if ( !Memcached::HAVE_IGBINARY ) {
 102                                         throw new InvalidArgumentException(
 103                                                 __CLASS__ . ': the igbinary extension is not available ' .
 104                                                 'but igbinary serialization was requested.'
 105                                         );
 106                                 }
 107                                 $this->client->setOption( Memcached::OPT_SERIALIZER, Memcached::SERIALIZER_IGBINARY );
 108                                 break;
 109                         default:
 110                                 throw new InvalidArgumentException(
 111                                         __CLASS__ . ': invalid value for serializer parameter'
 112                                 );
 113                 }
 114                 $servers = [];
 115                 foreach ( $params['servers'] as $host ) {
 116                         if ( preg_match( '/^\[(.+)\]:(\d+)$/', $host, $m ) ) {
 117                                 $servers[] = [ $m[1], (int)$m[2] ]; // (ip, port)
 118                         } elseif ( preg_match( '/^([^:]+):(\d+)$/', $host, $m ) ) {
 119                                 $servers[] = [ $m[1], (int)$m[2] ]; // (ip or path, port)
 120                         } else {
 121                                 $servers[] = [ $host, false ]; // (ip or path, port)
 122                         }
 123                 }
 124                 $this->client->addServers( $servers );
 125         }
 126
 127         protected function applyDefaultParams( $params ) {
 128                 $params = parent::applyDefaultParams( $params );
 129
 130                 if ( !isset( $params['use_binary_protocol'] ) ) {
 131                         $params['use_binary_protocol'] = false;
 132                 }
 133
 134                 if ( !isset( $params['serializer'] ) ) {
 135                         $params['serializer'] = 'php';
 136                 }
 137
 138                 return $params;
 139         }
 140
 141         protected function getWithToken( $key, &$casToken, $flags = 0 ) {
 142                 $this->debugLog( "get($key)" );
 143                 $result = $this->client->get( $this->validateKeyEncoding( $key ), null, $casToken );
 144                 $result = $this->checkResult( $key, $result );
 145                 return $result;
 146         }
 147
 148         public function set( $key, $value, $exptime = 0, $flags = 0 ) {
 149                 $this->debugLog( "set($key)" );
 150                 $result = parent::set( $key, $value, $exptime );
 151                 if ( $result === false && $this->client->getResultCode() === Memcached::RES_NOTSTORED ) {
 152                         // "Not stored" is always used as the mcrouter response with AllAsyncRoute
 153                         return true;
 154                 }
 155                 return $this->checkResult( $key, $result );
 156         }
 157
 158         protected function cas( $casToken, $key, $value, $exptime = 0 ) {
 159                 $this->debugLog( "cas($key)" );
 160                 return $this->checkResult( $key, parent::cas( $casToken, $key, $value, $exptime ) );
 161         }
 162
 163         public function delete( $key ) {
 164                 $this->debugLog( "delete($key)" );
 165                 $result = parent::delete( $key );
 166                 if ( $result === false && $this->client->getResultCode() === Memcached::RES_NOTFOUND ) {
 167                         // "Not found" is counted as success in our interface
 168                         return true;
 169                 }
 170                 return $this->checkResult( $key, $result );
 171         }
 172
 173         public function add( $key, $value, $exptime = 0 ) {
 174                 $this->debugLog( "add($key)" );
 175                 return $this->checkResult( $key, parent::add( $key, $value, $exptime ) );
 176         }
 177
 178         public function incr( $key, $value = 1 ) {
 179                 $this->debugLog( "incr($key)" );
 180                 $result = $this->client->increment( $key, $value );
 181                 return $this->checkResult( $key, $result );
 182         }
 183
 184         public function decr( $key, $value = 1 ) {
 185                 $this->debugLog( "decr($key)" );
 186                 $result = $this->client->decrement( $key, $value );
 187                 return $this->checkResult( $key, $result );
 188         }
 189
 190         /**
 191          * Check the return value from a client method call and take any necessary
 192          * action. Returns the value that the wrapper function should return. At
 193          * present, the return value is always the same as the return value from
 194          * the client, but some day we might find a case where it should be
 195          * different.
 196          *
 197          * @param string $key The key used by the caller, or false if there wasn't one.
 198          * @param mixed $result The return value
 199          * @return mixed
 200          */
 201         protected function checkResult( $key, $result ) {
 202                 if ( $result !== false ) {
 203                         return $result;
 204                 }
 205                 switch ( $this->client->getResultCode() ) {
 206                         case Memcached::RES_SUCCESS:
 207                                 break;
 208                         case Memcached::RES_DATA_EXISTS:
 209                         case Memcached::RES_NOTSTORED:
 210                         case Memcached::RES_NOTFOUND:
 211                                 $this->debugLog( "result: " . $this->client->getResultMessage() );
 212                                 break;
 213                         default:
 214                                 $msg = $this->client->getResultMessage();
 215                                 $logCtx = [];
 216                                 if ( $key !== false ) {
 217                                         $server = $this->client->getServerByKey( $key );
 218                                         $logCtx['memcached-server'] = "{$server['host']}:{$server['port']}";
 219                                         $logCtx['memcached-key'] = $key;
 220                                         $msg = "Memcached error for key \"{memcached-key}\" on server \"{memcached-server}\": $msg";
 221                                 } else {
 222                                         $msg = "Memcached error: $msg";
 223                                 }
 224                                 $this->logger->error( $msg, $logCtx );
 225                                 $this->setLastError( BagOStuff::ERR_UNEXPECTED );
 226                 }
 227                 return $result;
 228         }
 229
 230         public function getMulti( array $keys, $flags = 0 ) {
 231                 $this->debugLog( 'getMulti(' . implode( ', ', $keys ) . ')' );
 232                 foreach ( $keys as $key ) {
 233                         $this->validateKeyEncoding( $key );
 234                 }
 235                 $result = $this->client->getMulti( $keys ) ?: [];
 236                 return $this->checkResult( false, $result );
 237         }
 238
 239         /**
 240          * @param array $data
 241          * @param int $exptime
 242          * @return bool
 243          */
 244         public function setMulti( array $data, $exptime = 0 ) {
 245                 $this->debugLog( 'setMulti(' . implode( ', ', array_keys( $data ) ) . ')' );
 246                 foreach ( array_keys( $data ) as $key ) {
 247                         $this->validateKeyEncoding( $key );
 248                 }
 249                 $result = $this->client->setMulti( $data, $this->fixExpiry( $exptime ) );
 250                 return $this->checkResult( false, $result );
 251         }
 252
 253         public function changeTTL( $key, $expiry = 0 ) {
 254                 $this->debugLog( "touch($key)" );
 255                 $result = $this->client->touch( $key, $expiry );
 256                 return $this->checkResult( $key, $result );
 257         }
 258 }