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         function __construct( $params ) {
  37                 if ( !defined( 'CURLOPT_TIMEOUT_MS' ) ) {
  38                         throw new MWException( __CLASS__.' requires curl version 7.16.2 or later.' );
  39                 }
  40                 if ( !extension_loaded( 'zlib' ) ) {
  41                         throw new MWException( __CLASS__.' requires the zlib extension' );
  42                 }
  43                 if ( !isset( $params['servers'] ) ) {
  44                         throw new MWException( __METHOD__.': servers parameter is required' );
  45                 }
  46                 $this->servers = $params['servers'];
  47                 $this->cacheName = isset( $params['cache'] ) ? $params['cache'] : 'mw';
  48                 $this->connectTimeout = isset( $params['connectTimeout'] )
  49                         ? $params['connectTimeout'] : 1;
  50                 $this->timeout = isset( $params['timeout'] ) ? $params['timeout'] : 1;
  51                 $this->curlOptions = array(
  52                         CURLOPT_CONNECTTIMEOUT_MS => intval( $this->connectTimeout * 1000 ),
  53                         CURLOPT_TIMEOUT_MS => intval( $this->timeout * 1000 ),
  54                         CURLOPT_RETURNTRANSFER => 1,
  55                         CURLOPT_CUSTOMREQUEST => 'GET',
  56                         CURLOPT_POST => 0,
  57                         CURLOPT_POSTFIELDS => '',
  58                         CURLOPT_HTTPHEADER => array(),
  59                 );
  60         }
  61
  62         public function get( $key ) {
  63                 wfProfileIn( __METHOD__ );
  64                 $response = $this->doItemRequest( $key );
  65                 if ( !$response || $response['http_code'] == 404 ) {
  66                         wfProfileOut( __METHOD__ );
  67                         return false;
  68                 }
  69                 if ( $response['http_code'] >= 300 ) {
  70                         wfDebug( __METHOD__.": GET failure, got HTTP {$response['http_code']}\n" );
  71                         wfProfileOut( __METHOD__ );
  72                         return false;
  73                 }
  74                 $body = $response['body'];
  75                 $type = $response['content_type'];
  76                 if ( $type == 'application/vnd.php.serialized+deflate' ) {
  77                         $body = gzinflate( $body );
  78                         if ( !$body ) {
  79                                 wfDebug( __METHOD__.": error inflating $key\n" );
  80                                 wfProfileOut( __METHOD__ );
  81                                 return false;
  82                         }
  83                         $data = unserialize( $body );
  84                 } elseif ( $type == 'application/vnd.php.serialized' ) {
  85                         $data = unserialize( $body );
  86                 } else {
  87                         wfDebug( __METHOD__.": unknown content type \"$type\"\n" );
  88                         wfProfileOut( __METHOD__ );
  89                         return false;
  90                 }
  91
  92                 wfProfileOut( __METHOD__ );
  93                 return $data;
  94         }
  95
  96         public function set( $key, $value, $expiry = 0 ) {
  97                 wfProfileIn( __METHOD__ );
  98                 $expiry = $this->convertExpiry( $expiry );
  99                 $ttl = $expiry ? $expiry - time() : 2147483647;
 100                 $blob = serialize( $value );
 101                 if ( strlen( $blob ) > 100 ) {
 102                         $blob = gzdeflate( $blob );
 103                         $contentType = 'application/vnd.php.serialized+deflate';
 104                 } else {
 105                         $contentType = 'application/vnd.php.serialized';
 106                 }
 107
 108                 $code = $this->attemptPut( $key, $blob, $contentType, $ttl );
 109
 110                 if ( $code == 404 ) {
 111                         // Maybe the cache does not exist yet, let's try creating it
 112                         if ( !$this->createCache( $key ) ) {
 113                                 wfDebug( __METHOD__.": cache creation failed\n" );
 114                                 wfProfileOut( __METHOD__ );
 115                                 return false;
 116                         }
 117                         $code = $this->attemptPut( $key, $blob, $contentType, $ttl );
 118                 }
 119
 120                 $result = false;
 121                 if ( !$code ) {
 122                         wfDebug( __METHOD__.": PUT failure for key $key\n" );
 123                 } elseif ( $code >= 300 ) {
 124                         wfDebug( __METHOD__.": PUT failure for key $key: HTTP $code\n" );
 125                 } else {
 126                         $result = true;
 127                 }
 128
 129                 wfProfileOut( __METHOD__ );
 130                 return $result;
 131         }
 132
 133         public function delete( $key, $time = 0 ) {
 134                 wfProfileIn( __METHOD__ );
 135                 $response = $this->doItemRequest( $key,
 136                         array( CURLOPT_CUSTOMREQUEST => 'DELETE' ) );
 137                 $code = isset( $response['http_code'] ) ? $response['http_code'] : 0;
 138                 if ( !$response || ( $code != 404 && $code >= 300 ) ) {
 139                         wfDebug( __METHOD__.": DELETE failure for key $key\n" );
 140                         $result = false;
 141                 } else {
 142                         $result = true;
 143                 }
 144                 wfProfileOut( __METHOD__ );
 145                 return $result;
 146         }
 147
 148         protected function getCacheUrl( $key ) {
 149                 if ( count( $this->servers ) == 1 ) {
 150                         $server = reset( $this->servers );
 151                 } else {
 152                         // Use consistent hashing
 153                         $hashes = array();
 154                         foreach ( $this->servers as $server ) {
 155                                 $hashes[$server] = md5( $server . '/' . $key );
 156                         }
 157                         asort( $hashes );
 158                         reset( $hashes );
 159                         $server = key( $hashes );
 160                 }
 161                 return "http://$server/ehcache/rest/{$this->cacheName}";
 162         }
 163
 164         /**
 165          * Get a cURL handle for the given cache URL.
 166          * We cache the handles to allow keepalive.
 167          */
 168         protected function getCurl( $cacheUrl ) {
 169                 if ( !isset( $this->curls[$cacheUrl] ) ) {
 170                         $this->curls[$cacheUrl] = curl_init();
 171                 }
 172                 return $this->curls[$cacheUrl];
 173         }
 174
 175         protected function attemptPut( $key, $data, $type, $ttl ) {
 176                 // In initial benchmarking, it was 30 times faster to use CURLOPT_POST
 177                 // than CURLOPT_UPLOAD with CURLOPT_READFUNCTION. This was because
 178                 // CURLOPT_UPLOAD was pushing the request headers first, then waiting
 179                 // for an ACK packet, then sending the data, whereas CURLOPT_POST just
 180                 // sends the headers and the data in a single send().
 181                 $response = $this->doItemRequest( $key,
 182                         array(
 183                                 CURLOPT_POST => 1,
 184                                 CURLOPT_CUSTOMREQUEST => 'PUT',
 185                                 CURLOPT_POSTFIELDS => $data,
 186                                 CURLOPT_HTTPHEADER => array(
 187                                         'Content-Type: ' . $type,
 188                                         'ehcacheTimeToLiveSeconds: ' . $ttl
 189                                 )
 190                         )
 191                 );
 192                 if ( !$response ) {
 193                         return 0;
 194                 } else {
 195                         return $response['http_code'];
 196                 }
 197         }
 198
 199         protected function createCache( $key ) {
 200                 wfDebug( __METHOD__.": creating cache for $key\n" );
 201                 $response = $this->doCacheRequest( $key,
 202                         array(
 203                                 CURLOPT_POST => 1,
 204                                 CURLOPT_CUSTOMREQUEST => 'PUT',
 205                                 CURLOPT_POSTFIELDS => '',
 206                         ) );
 207                 if ( !$response ) {
 208                         wfDebug( __CLASS__.": failed to create cache for $key\n" );
 209                         return false;
 210                 }
 211                 if ( $response['http_code'] == 201 /* created */
 212                         || $response['http_code'] == 409 /* already there */ )
 213                 {
 214                         return true;
 215                 } else {
 216                         return false;
 217                 }
 218         }
 219
 220         protected function doCacheRequest( $key, $curlOptions = array() ) {
 221                 $cacheUrl = $this->getCacheUrl( $key );
 222                 $curl = $this->getCurl( $cacheUrl );
 223                 return $this->doRequest( $curl, $cacheUrl, $curlOptions );
 224         }
 225
 226         protected function doItemRequest( $key, $curlOptions = array() ) {
 227                 $cacheUrl = $this->getCacheUrl( $key );
 228                 $curl = $this->getCurl( $cacheUrl );
 229                 $url = $cacheUrl . '/' . rawurlencode( $key );
 230                 return $this->doRequest( $curl, $url, $curlOptions );
 231         }
 232
 233         protected function doRequest( $curl, $url, $curlOptions = array() ) {
 234                 if ( array_diff_key( $curlOptions, $this->curlOptions ) ) {
 235                         // var_dump( array_diff_key( $curlOptions, $this->curlOptions ) );
 236                         throw new MWException( __METHOD__.": to prevent options set in one doRequest() " .
 237                                 "call from affecting subsequent doRequest() calls, only options listed " .
 238                                 "in \$this->curlOptions may be specified in the \$curlOptions parameter." );
 239                 }
 240                 $curlOptions += $this->curlOptions;
 241                 $curlOptions[CURLOPT_URL] = $url;
 242
 243                 curl_setopt_array( $curl, $curlOptions );
 244                 $result = curl_exec( $curl );
 245                 if ( $result === false ) {
 246                         wfDebug( __CLASS__.": curl error: " . curl_error( $curl ) . "\n" );
 247                         return false;
 248                 }
 249                 $info = curl_getinfo( $curl );
 250                 $info['body'] = $result;
 251                 return $info;
 252         }
 253 }