includes/objectcache/EhcacheBagOStuff.php

   1 <?php
   2 /**
   3  * Object caching using the Ehcache RESTful web service.
   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  * Client for the Ehcache RESTful web service - http://ehcache.org/documentation/cache_server.html
  26  * TODO: Simplify configuration and add to the installer.
  27  *
  28  * @ingroup Cache
  29  */
  30 class EhcacheBagOStuff extends BagOStuff {
  31         var $servers, $cacheName, $connectTimeout, $timeout, $curlOptions,
  32                 $requestData, $requestDataPos;
  33
  34         var $curls = array();
  35
  36         /**
  37          * @param $params array
  38          * @throws MWException
  39          */
  40         function __construct( $params ) {
  41                 if ( !defined( 'CURLOPT_TIMEOUT_MS' ) ) {
  42                         throw new MWException( __CLASS__.' requires curl version 7.16.2 or later.' );
  43                 }
  44                 if ( !extension_loaded( 'zlib' ) ) {
  45                         throw new MWException( __CLASS__.' requires the zlib extension' );
  46                 }
  47                 if ( !isset( $params['servers'] ) ) {
  48                         throw new MWException( __METHOD__.': servers parameter is required' );
  49                 }
  50                 $this->servers = $params['servers'];
  51                 $this->cacheName = isset( $params['cache'] ) ? $params['cache'] : 'mw';
  52                 $this->connectTimeout = isset( $params['connectTimeout'] )
  53                         ? $params['connectTimeout'] : 1;
  54                 $this->timeout = isset( $params['timeout'] ) ? $params['timeout'] : 1;
  55                 $this->curlOptions = array(
  56                         CURLOPT_CONNECTTIMEOUT_MS => intval( $this->connectTimeout * 1000 ),
  57                         CURLOPT_TIMEOUT_MS => intval( $this->timeout * 1000 ),
  58                         CURLOPT_RETURNTRANSFER => 1,
  59                         CURLOPT_CUSTOMREQUEST => 'GET',
  60                         CURLOPT_POST => 0,
  61                         CURLOPT_POSTFIELDS => '',
  62                         CURLOPT_HTTPHEADER => array(),
  63                 );
  64         }
  65
  66         /**
  67          * @param $key string
  68          * @param $casToken[optional] mixed
  69          * @return bool|mixed
  70          */
  71         public function get( $key, &$casToken = null ) {
  72                 wfProfileIn( __METHOD__ );
  73                 $response = $this->doItemRequest( $key );
  74                 if ( !$response || $response['http_code'] == 404 ) {
  75                         wfProfileOut( __METHOD__ );
  76                         return false;
  77                 }
  78                 if ( $response['http_code'] >= 300 ) {
  79                         wfDebug( __METHOD__.": GET failure, got HTTP {$response['http_code']}\n" );
  80                         wfProfileOut( __METHOD__ );
  81                         return false;
  82                 }
  83                 $body = $response['body'];
  84                 $type = $response['content_type'];
  85                 if ( $type == 'application/vnd.php.serialized+deflate' ) {
  86                         $body = gzinflate( $body );
  87                         if ( !$body ) {
  88                                 wfDebug( __METHOD__.": error inflating $key\n" );
  89                                 wfProfileOut( __METHOD__ );
  90                                 return false;
  91                         }
  92                         $data = unserialize( $body );
  93                 } elseif ( $type == 'application/vnd.php.serialized' ) {
  94                         $data = unserialize( $body );
  95                 } else {
  96                         wfDebug( __METHOD__.": unknown content type \"$type\"\n" );
  97                         wfProfileOut( __METHOD__ );
  98                         return false;
  99                 }
 100
 101                 $casToken = $body;
 102
 103                 wfProfileOut( __METHOD__ );
 104                 return $data;
 105         }
 106
 107         /**
 108          * @param $key string
 109          * @param $value mixed
 110          * @param $expiry int
 111          * @return bool
 112          */
 113         public function set( $key, $value, $expiry = 0 ) {
 114                 wfProfileIn( __METHOD__ );
 115                 $expiry = $this->convertExpiry( $expiry );
 116                 $ttl = $expiry ? $expiry - time() : 2147483647;
 117                 $blob = serialize( $value );
 118                 if ( strlen( $blob ) > 100 ) {
 119                         $blob = gzdeflate( $blob );
 120                         $contentType = 'application/vnd.php.serialized+deflate';
 121                 } else {
 122                         $contentType = 'application/vnd.php.serialized';
 123                 }
 124
 125                 $code = $this->attemptPut( $key, $blob, $contentType, $ttl );
 126
 127                 if ( $code == 404 ) {
 128                         // Maybe the cache does not exist yet, let's try creating it
 129                         if ( !$this->createCache( $key ) ) {
 130                                 wfDebug( __METHOD__.": cache creation failed\n" );
 131                                 wfProfileOut( __METHOD__ );
 132                                 return false;
 133                         }
 134                         $code = $this->attemptPut( $key, $blob, $contentType, $ttl );
 135                 }
 136
 137                 $result = false;
 138                 if ( !$code ) {
 139                         wfDebug( __METHOD__.": PUT failure for key $key\n" );
 140                 } elseif ( $code >= 300 ) {
 141                         wfDebug( __METHOD__.": PUT failure for key $key: HTTP $code\n" );
 142                 } else {
 143                         $result = true;
 144                 }
 145
 146                 wfProfileOut( __METHOD__ );
 147                 return $result;
 148         }
 149
 150         /**
 151          * @param $casToken mixed
 152          * @param $key string
 153          * @param $value mixed
 154          * @param $exptime int
 155          * @return bool
 156          */
 157         public function cas( $casToken, $key, $value, $exptime = 0 ) {
 158                 // Not sure if we can implement CAS for ehcache. There appears to be CAS-support per
 159                 // http://ehcache.org/documentation/get-started/consistency-options#cas-cache-operations,
 160                 // but I can't find any docs for our current implementation.
 161                 throw new MWException( "CAS is not implemented in " . __CLASS__ );
 162         }
 163
 164         /**
 165          * @param $key string
 166          * @param $time int
 167          * @return bool
 168          */
 169         public function delete( $key, $time = 0 ) {
 170                 wfProfileIn( __METHOD__ );
 171                 $response = $this->doItemRequest( $key,
 172                         array( CURLOPT_CUSTOMREQUEST => 'DELETE' ) );
 173                 $code = isset( $response['http_code'] ) ? $response['http_code'] : 0;
 174                 if ( !$response || ( $code != 404 && $code >= 300 ) ) {
 175                         wfDebug( __METHOD__.": DELETE failure for key $key\n" );
 176                         $result = false;
 177                 } else {
 178                         $result = true;
 179                 }
 180                 wfProfileOut( __METHOD__ );
 181                 return $result;
 182         }
 183
 184         /**
 185          * @see BagOStuff::merge()
 186          * @return bool success
 187          */
 188         public function merge( $key, closure $callback, $exptime = 0, $attempts = 10 ) {
 189                 return $this->mergeViaLock( $key, $callback, $exptime, $attempts );
 190         }
 191
 192         /**
 193          * @param $key string
 194          * @return string
 195          */
 196         protected function getCacheUrl( $key ) {
 197                 if ( count( $this->servers ) == 1 ) {
 198                         $server = reset( $this->servers );
 199                 } else {
 200                         // Use consistent hashing
 201                         $hashes = array();
 202                         foreach ( $this->servers as $server ) {
 203                                 $hashes[$server] = md5( $server . '/' . $key );
 204                         }
 205                         asort( $hashes );
 206                         reset( $hashes );
 207                         $server = key( $hashes );
 208                 }
 209                 return "http://$server/ehcache/rest/{$this->cacheName}";
 210         }
 211
 212         /**
 213          * Get a cURL handle for the given cache URL.
 214          * We cache the handles to allow keepalive.
 215          */
 216         protected function getCurl( $cacheUrl ) {
 217                 if ( !isset( $this->curls[$cacheUrl] ) ) {
 218                         $this->curls[$cacheUrl] = curl_init();
 219                 }
 220                 return $this->curls[$cacheUrl];
 221         }
 222
 223         /**
 224          * @param $key string
 225          * @param $data
 226          * @param $type
 227          * @param $ttl
 228          * @return int
 229          */
 230         protected function attemptPut( $key, $data, $type, $ttl ) {
 231                 // In initial benchmarking, it was 30 times faster to use CURLOPT_POST
 232                 // than CURLOPT_UPLOAD with CURLOPT_READFUNCTION. This was because
 233                 // CURLOPT_UPLOAD was pushing the request headers first, then waiting
 234                 // for an ACK packet, then sending the data, whereas CURLOPT_POST just
 235                 // sends the headers and the data in a single send().
 236                 $response = $this->doItemRequest( $key,
 237                         array(
 238                                 CURLOPT_POST => 1,
 239                                 CURLOPT_CUSTOMREQUEST => 'PUT',
 240                                 CURLOPT_POSTFIELDS => $data,
 241                                 CURLOPT_HTTPHEADER => array(
 242                                         'Content-Type: ' . $type,
 243                                         'ehcacheTimeToLiveSeconds: ' . $ttl
 244                                 )
 245                         )
 246                 );
 247                 if ( !$response ) {
 248                         return 0;
 249                 } else {
 250                         return $response['http_code'];
 251                 }
 252         }
 253
 254         /**
 255          * @param $key string
 256          * @return bool
 257          */
 258         protected function createCache( $key ) {
 259                 wfDebug( __METHOD__.": creating cache for $key\n" );
 260                 $response = $this->doCacheRequest( $key,
 261                         array(
 262                                 CURLOPT_POST => 1,
 263                                 CURLOPT_CUSTOMREQUEST => 'PUT',
 264                                 CURLOPT_POSTFIELDS => '',
 265                         ) );
 266                 if ( !$response ) {
 267                         wfDebug( __CLASS__.": failed to create cache for $key\n" );
 268                         return false;
 269                 }
 270                 return ( $response['http_code'] == 201 /* created */
 271                         || $response['http_code'] == 409 /* already there */ );
 272         }
 273
 274         /**
 275          * @param $key string
 276          * @param $curlOptions array
 277          * @return array|bool|mixed
 278          */
 279         protected function doCacheRequest( $key, $curlOptions = array() ) {
 280                 $cacheUrl = $this->getCacheUrl( $key );
 281                 $curl = $this->getCurl( $cacheUrl );
 282                 return $this->doRequest( $curl, $cacheUrl, $curlOptions );
 283         }
 284
 285         /**
 286          * @param $key string
 287          * @param $curlOptions array
 288          * @return array|bool|mixed
 289          */
 290         protected function doItemRequest( $key, $curlOptions = array() ) {
 291                 $cacheUrl = $this->getCacheUrl( $key );
 292                 $curl = $this->getCurl( $cacheUrl );
 293                 $url = $cacheUrl . '/' . rawurlencode( $key );
 294                 return $this->doRequest( $curl, $url, $curlOptions );
 295         }
 296
 297         /**
 298          * @param $curl
 299          * @param $url string
 300          * @param $curlOptions array
 301          * @return array|bool|mixed
 302          * @throws MWException
 303          */
 304         protected function doRequest( $curl, $url, $curlOptions = array() ) {
 305                 if ( array_diff_key( $curlOptions, $this->curlOptions ) ) {
 306                         // var_dump( array_diff_key( $curlOptions, $this->curlOptions ) );
 307                         throw new MWException( __METHOD__.": to prevent options set in one doRequest() " .
 308                                 "call from affecting subsequent doRequest() calls, only options listed " .
 309                                 "in \$this->curlOptions may be specified in the \$curlOptions parameter." );
 310                 }
 311                 $curlOptions += $this->curlOptions;
 312                 $curlOptions[CURLOPT_URL] = $url;
 313
 314                 curl_setopt_array( $curl, $curlOptions );
 315                 $result = curl_exec( $curl );
 316                 if ( $result === false ) {
 317                         wfDebug( __CLASS__.": curl error: " . curl_error( $curl ) . "\n" );
 318                         return false;
 319                 }
 320                 $info = curl_getinfo( $curl );
 321                 $info['body'] = $result;
 322                 return $info;
 323         }
 324 }