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         /** @var Memcached */
  31         protected $client;
  32
  33         /**
  34          * Available parameters are:
  35          *   - servers:             The list of IP:port combinations holding the memcached servers.
  36          *   - persistent:          Whether to use a persistent connection
  37          *   - compress_threshold:  The minimum size an object must be before it is compressed
  38          *   - timeout:             The read timeout in microseconds
  39          *   - connect_timeout:     The connect timeout in seconds
  40          *   - retry_timeout:       Time in seconds to wait before retrying a failed connect attempt
  41          *   - server_failure_limit:  Limit for server connect failures before it is removed
  42          *   - serializer:          May be either "php" or "igbinary". Igbinary produces more compact
  43          *                          values, but serialization is much slower unless the php.ini option
  44          *                          igbinary.compact_strings is off.
  45          *   - use_binary_protocol  Whether to enable the binary protocol (default is ASCII) (boolean)
  46          * @param array $params
  47          * @throws InvalidArgumentException
  48          */
  49         function __construct( $params ) {
  50                 parent::__construct( $params );
  51                 $params = $this->applyDefaultParams( $params );
  52
  53                 if ( $params['persistent'] ) {
  54                         // The pool ID must be unique to the server/option combination.
  55                         // The Memcached object is essentially shared for each pool ID.
  56                         // We can only reuse a pool ID if we keep the config consistent.
  57                         $this->client = new Memcached( md5( serialize( $params ) ) );
  58                         if ( count( $this->client->getServerList() ) ) {
  59                                 $this->logger->debug( __METHOD__ . ": persistent Memcached object already loaded." );
  60                                 return; // already initialized; don't add duplicate servers
  61                         }
  62                 } else {
  63                         $this->client = new Memcached;
  64                 }
  65
  66                 if ( $params['use_binary_protocol'] ) {
  67                         $this->client->setOption( Memcached::OPT_BINARY_PROTOCOL, true );
  68                 }
  69
  70                 if ( isset( $params['retry_timeout'] ) ) {
  71                         $this->client->setOption( Memcached::OPT_RETRY_TIMEOUT, $params['retry_timeout'] );
  72                 }
  73
  74                 if ( isset( $params['server_failure_limit'] ) ) {
  75                         $this->client->setOption( Memcached::OPT_SERVER_FAILURE_LIMIT, $params['server_failure_limit'] );
  76                 }
  77
  78                 // The compression threshold is an undocumented php.ini option for some
  79                 // reason. There's probably not much harm in setting it globally, for
  80                 // compatibility with the settings for the PHP client.
  81                 ini_set( 'memcached.compression_threshold', $params['compress_threshold'] );
  82
  83                 // Set timeouts
  84                 $this->client->setOption( Memcached::OPT_CONNECT_TIMEOUT, $params['connect_timeout'] * 1000 );
  85                 $this->client->setOption( Memcached::OPT_SEND_TIMEOUT, $params['timeout'] );
  86                 $this->client->setOption( Memcached::OPT_RECV_TIMEOUT, $params['timeout'] );
  87                 $this->client->setOption( Memcached::OPT_POLL_TIMEOUT, $params['timeout'] / 1000 );
  88
  89                 // Set libketama mode since it's recommended by the documentation and
  90                 // is as good as any. There's no way to configure libmemcached to use
  91                 // hashes identical to the ones currently in use by the PHP client, and
  92                 // even implementing one of the libmemcached hashes in pure PHP for
  93                 // forwards compatibility would require MemcachedClient::get_sock() to be
  94                 // rewritten.
  95                 $this->client->setOption( Memcached::OPT_LIBKETAMA_COMPATIBLE, true );
  96
  97                 // Set the serializer
  98                 $ok = false;
  99                 if ( $params['serializer'] === 'php' ) {
 100                         $ok = $this->client->setOption( Memcached::OPT_SERIALIZER, Memcached::SERIALIZER_PHP );
 101                 } elseif ( $params['serializer'] === 'igbinary' ) {
 102                         if ( !Memcached::HAVE_IGBINARY ) {
 103                                 throw new InvalidArgumentException(
 104                                         __CLASS__ . ': the igbinary extension is not available ' .
 105                                         'but igbinary serialization was requested.'
 106                                 );
 107                         }
 108                         $ok = $this->client->setOption( Memcached::OPT_SERIALIZER, Memcached::SERIALIZER_IGBINARY );
 109                 }
 110                 if ( !$ok ) {
 111                         throw new InvalidArgumentException( __CLASS__ . ': invalid 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 doGet( $key, $flags = 0, &$casToken = null ) {
 142                 $this->debug( "get($key)" );
 143                 if ( defined( Memcached::class . '::GET_EXTENDED' ) ) { // v3.0.0
 144                         $flags = Memcached::GET_EXTENDED;
 145                         $res = $this->client->get( $this->validateKeyEncoding( $key ), null, $flags );
 146                         if ( is_array( $res ) ) {
 147                                 $result = $res['value'];
 148                                 $casToken = $res['cas'];
 149                         } else {
 150                                 $result = false;
 151                                 $casToken = null;
 152                         }
 153                 } else {
 154                         $result = $this->client->get( $this->validateKeyEncoding( $key ), null, $casToken );
 155                 }
 156                 $result = $this->checkResult( $key, $result );
 157                 return $result;
 158         }
 159
 160         protected function doSet( $key, $value, $exptime = 0, $flags = 0 ) {
 161                 $this->debug( "set($key)" );
 162                 $result = $this->client->set(
 163                         $this->validateKeyEncoding( $key ),
 164                         $value,
 165                         $this->fixExpiry( $exptime )
 166                 );
 167                 if ( $result === false && $this->client->getResultCode() === Memcached::RES_NOTSTORED ) {
 168                         // "Not stored" is always used as the mcrouter response with AllAsyncRoute
 169                         return true;
 170                 }
 171                 return $this->checkResult( $key, $result );
 172         }
 173
 174         protected function cas( $casToken, $key, $value, $exptime = 0, $flags = 0 ) {
 175                 $this->debug( "cas($key)" );
 176                 $result = $this->client->cas( $casToken, $this->validateKeyEncoding( $key ),
 177                         $value, $this->fixExpiry( $exptime ) );
 178                 return $this->checkResult( $key, $result );
 179         }
 180
 181         protected function doDelete( $key, $flags = 0 ) {
 182                 $this->debug( "delete($key)" );
 183                 $result = $this->client->delete( $this->validateKeyEncoding( $key ) );
 184                 if ( $result === false && $this->client->getResultCode() === Memcached::RES_NOTFOUND ) {
 185                         // "Not found" is counted as success in our interface
 186                         return true;
 187                 }
 188                 return $this->checkResult( $key, $result );
 189         }
 190
 191         public function add( $key, $value, $exptime = 0, $flags = 0 ) {
 192                 $this->debug( "add($key)" );
 193                 $result = $this->client->add(
 194                         $this->validateKeyEncoding( $key ),
 195                         $value,
 196                         $this->fixExpiry( $exptime )
 197                 );
 198                 return $this->checkResult( $key, $result );
 199         }
 200
 201         public function incr( $key, $value = 1 ) {
 202                 $this->debug( "incr($key)" );
 203                 $result = $this->client->increment( $key, $value );
 204                 return $this->checkResult( $key, $result );
 205         }
 206
 207         public function decr( $key, $value = 1 ) {
 208                 $this->debug( "decr($key)" );
 209                 $result = $this->client->decrement( $key, $value );
 210                 return $this->checkResult( $key, $result );
 211         }
 212
 213         /**
 214          * Check the return value from a client method call and take any necessary
 215          * action. Returns the value that the wrapper function should return. At
 216          * present, the return value is always the same as the return value from
 217          * the client, but some day we might find a case where it should be
 218          * different.
 219          *
 220          * @param string $key The key used by the caller, or false if there wasn't one.
 221          * @param mixed $result The return value
 222          * @return mixed
 223          */
 224         protected function checkResult( $key, $result ) {
 225                 if ( $result !== false ) {
 226                         return $result;
 227                 }
 228                 switch ( $this->client->getResultCode() ) {
 229                         case Memcached::RES_SUCCESS:
 230                                 break;
 231                         case Memcached::RES_DATA_EXISTS:
 232                         case Memcached::RES_NOTSTORED:
 233                         case Memcached::RES_NOTFOUND:
 234                                 $this->debug( "result: " . $this->client->getResultMessage() );
 235                                 break;
 236                         default:
 237                                 $msg = $this->client->getResultMessage();
 238                                 $logCtx = [];
 239                                 if ( $key !== false ) {
 240                                         $server = $this->client->getServerByKey( $key );
 241                                         $logCtx['memcached-server'] = "{$server['host']}:{$server['port']}";
 242                                         $logCtx['memcached-key'] = $key;
 243                                         $msg = "Memcached error for key \"{memcached-key}\" on server \"{memcached-server}\": $msg";
 244                                 } else {
 245                                         $msg = "Memcached error: $msg";
 246                                 }
 247                                 $this->logger->error( $msg, $logCtx );
 248                                 $this->setLastError( BagOStuff::ERR_UNEXPECTED );
 249                 }
 250                 return $result;
 251         }
 252
 253         public function doGetMulti( array $keys, $flags = 0 ) {
 254                 $this->debug( 'getMulti(' . implode( ', ', $keys ) . ')' );
 255                 foreach ( $keys as $key ) {
 256                         $this->validateKeyEncoding( $key );
 257                 }
 258                 $result = $this->client->getMulti( $keys ) ?: [];
 259                 return $this->checkResult( false, $result );
 260         }
 261
 262         public function setMulti( array $data, $exptime = 0, $flags = 0 ) {
 263                 $this->debug( 'setMulti(' . implode( ', ', array_keys( $data ) ) . ')' );
 264                 foreach ( array_keys( $data ) as $key ) {
 265                         $this->validateKeyEncoding( $key );
 266                 }
 267                 $result = $this->client->setMulti( $data, $this->fixExpiry( $exptime ) );
 268                 return $this->checkResult( false, $result );
 269         }
 270
 271         public function deleteMulti( array $keys, $flags = 0 ) {
 272                 $this->debug( 'deleteMulti(' . implode( ', ', $keys ) . ')' );
 273                 foreach ( $keys as $key ) {
 274                         $this->validateKeyEncoding( $key );
 275                 }
 276                 $result = $this->client->deleteMulti( $keys ) ?: [];
 277                 $ok = true;
 278                 foreach ( $result as $code ) {
 279                         if ( !in_array( $code, [ true, Memcached::RES_NOTFOUND ], true ) ) {
 280                                 // "Not found" is counted as success in our interface
 281                                 $ok = false;
 282                         }
 283                 }
 284                 return $this->checkResult( false, $ok );
 285         }
 286
 287         public function changeTTL( $key, $exptime = 0, $flags = 0 ) {
 288                 $this->debug( "touch($key)" );
 289                 $result = $this->client->touch( $key, $exptime );
 290                 return $this->checkResult( $key, $result );
 291         }
 292
 293         protected function serialize( $value ) {
 294                 if ( is_int( $value ) ) {
 295                         return $value;
 296                 }
 297
 298                 $serializer = $this->client->getOption( Memcached::OPT_SERIALIZER );
 299                 if ( $serializer === Memcached::SERIALIZER_PHP ) {
 300                         return serialize( $value );
 301                 } elseif ( $serializer === Memcached::SERIALIZER_IGBINARY ) {
 302                         return igbinary_serialize( $value );
 303                 }
 304
 305                 throw new UnexpectedValueException( __METHOD__ . ": got serializer '$serializer'." );
 306         }
 307
 308         protected function unserialize( $value ) {
 309                 if ( $this->isInteger( $value ) ) {
 310                         return (int)$value;
 311                 }
 312
 313                 $serializer = $this->client->getOption( Memcached::OPT_SERIALIZER );
 314                 if ( $serializer === Memcached::SERIALIZER_PHP ) {
 315                         return unserialize( $value );
 316                 } elseif ( $serializer === Memcached::SERIALIZER_IGBINARY ) {
 317                         return igbinary_unserialize( $value );
 318                 }
 319
 320                 throw new UnexpectedValueException( __METHOD__ . ": got serializer '$serializer'." );
 321         }
 322 }