includes/deferred/SiteStatsUpdate.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  */
  20
  21 /**
  22  * Class for handling updates to the site_stats table
  23  */
  24 class SiteStatsUpdate implements DeferrableUpdate {
  25         /** @var int */
  26         protected $edits = 0;
  27
  28         /** @var int */
  29         protected $pages = 0;
  30
  31         /** @var int */
  32         protected $articles = 0;
  33
  34         /** @var int */
  35         protected $users = 0;
  36
  37         /** @var int */
  38         protected $images = 0;
  39
  40         // @todo deprecate this constructor
  41         function __construct( $views, $edits, $good, $pages = 0, $users = 0 ) {
  42                 $this->edits = $edits;
  43                 $this->articles = $good;
  44                 $this->pages = $pages;
  45                 $this->users = $users;
  46         }
  47
  48         /**
  49          * @param array $deltas
  50          * @return SiteStatsUpdate
  51          */
  52         public static function factory( array $deltas ) {
  53                 $update = new self( 0, 0, 0 );
  54
  55                 $fields = array( 'views', 'edits', 'pages', 'articles', 'users', 'images' );
  56                 foreach ( $fields as $field ) {
  57                         if ( isset( $deltas[$field] ) && $deltas[$field] ) {
  58                                 $update->$field = $deltas[$field];
  59                         }
  60                 }
  61
  62                 return $update;
  63         }
  64
  65         public function doUpdate() {
  66                 global $wgSiteStatsAsyncFactor;
  67
  68                 $rate = $wgSiteStatsAsyncFactor; // convenience
  69                 // If set to do so, only do actual DB updates 1 every $rate times.
  70                 // The other times, just update "pending delta" values in memcached.
  71                 if ( $rate && ( $rate < 0 || mt_rand( 0, $rate - 1 ) != 0 ) ) {
  72                         $this->doUpdatePendingDeltas();
  73                 } else {
  74                         // Need a separate transaction because this a global lock
  75                         wfGetDB( DB_MASTER )->onTransactionIdle( array( $this, 'tryDBUpdateInternal' ) );
  76                 }
  77         }
  78
  79         /**
  80          * Do not call this outside of SiteStatsUpdate
  81          */
  82         public function tryDBUpdateInternal() {
  83                 global $wgSiteStatsAsyncFactor;
  84
  85                 $dbw = wfGetDB( DB_MASTER );
  86                 $lockKey = wfMemcKey( 'site_stats' ); // prepend wiki ID
  87                 $pd = array();
  88                 if ( $wgSiteStatsAsyncFactor ) {
  89                         // Lock the table so we don't have double DB/memcached updates
  90                         if ( !$dbw->lockIsFree( $lockKey, __METHOD__ )
  91                                 || !$dbw->lock( $lockKey, __METHOD__, 1 ) // 1 sec timeout
  92                         ) {
  93                                 $this->doUpdatePendingDeltas();
  94
  95                                 return;
  96                         }
  97                         $pd = $this->getPendingDeltas();
  98                         // Piggy-back the async deltas onto those of this stats update....
  99                         $this->edits += ( $pd['ss_total_edits']['+'] - $pd['ss_total_edits']['-'] );
 100                         $this->articles += ( $pd['ss_good_articles']['+'] - $pd['ss_good_articles']['-'] );
 101                         $this->pages += ( $pd['ss_total_pages']['+'] - $pd['ss_total_pages']['-'] );
 102                         $this->users += ( $pd['ss_users']['+'] - $pd['ss_users']['-'] );
 103                         $this->images += ( $pd['ss_images']['+'] - $pd['ss_images']['-'] );
 104                 }
 105
 106                 // Build up an SQL query of deltas and apply them...
 107                 $updates = '';
 108                 $this->appendUpdate( $updates, 'ss_total_edits', $this->edits );
 109                 $this->appendUpdate( $updates, 'ss_good_articles', $this->articles );
 110                 $this->appendUpdate( $updates, 'ss_total_pages', $this->pages );
 111                 $this->appendUpdate( $updates, 'ss_users', $this->users );
 112                 $this->appendUpdate( $updates, 'ss_images', $this->images );
 113                 if ( $updates != '' ) {
 114                         $dbw->update( 'site_stats', array( $updates ), array(), __METHOD__ );
 115                 }
 116
 117                 if ( $wgSiteStatsAsyncFactor ) {
 118                         // Decrement the async deltas now that we applied them
 119                         $this->removePendingDeltas( $pd );
 120                         // Commit the updates and unlock the table
 121                         $dbw->unlock( $lockKey, __METHOD__ );
 122                 }
 123         }
 124
 125         /**
 126          * @param DatabaseBase $dbw
 127          * @return bool|mixed
 128          */
 129         public static function cacheUpdate( $dbw ) {
 130                 global $wgActiveUserDays;
 131                 $dbr = wfGetDB( DB_SLAVE, array( 'SpecialStatistics', 'vslow' ) );
 132                 # Get non-bot users than did some recent action other than making accounts.
 133                 # If account creation is included, the number gets inflated ~20+ fold on enwiki.
 134                 $activeUsers = $dbr->selectField(
 135                         'recentchanges',
 136                         'COUNT( DISTINCT rc_user_text )',
 137                         array(
 138                                 'rc_user != 0',
 139                                 'rc_bot' => 0,
 140                                 'rc_log_type != ' . $dbr->addQuotes( 'newusers' ) . ' OR rc_log_type IS NULL',
 141                                 'rc_timestamp >= ' . $dbr->addQuotes( $dbr->timestamp( wfTimestamp( TS_UNIX )
 142                                         - $wgActiveUserDays * 24 * 3600 ) ),
 143                         ),
 144                         __METHOD__
 145                 );
 146                 $dbw->update(
 147                         'site_stats',
 148                         array( 'ss_active_users' => intval( $activeUsers ) ),
 149                         array( 'ss_row_id' => 1 ),
 150                         __METHOD__
 151                 );
 152
 153                 return $activeUsers;
 154         }
 155
 156         protected function doUpdatePendingDeltas() {
 157                 $this->adjustPending( 'ss_total_edits', $this->edits );
 158                 $this->adjustPending( 'ss_good_articles', $this->articles );
 159                 $this->adjustPending( 'ss_total_pages', $this->pages );
 160                 $this->adjustPending( 'ss_users', $this->users );
 161                 $this->adjustPending( 'ss_images', $this->images );
 162         }
 163
 164         /**
 165          * @param string $sql
 166          * @param string $field
 167          * @param int $delta
 168          */
 169         protected function appendUpdate( &$sql, $field, $delta ) {
 170                 if ( $delta ) {
 171                         if ( $sql ) {
 172                                 $sql .= ',';
 173                         }
 174                         if ( $delta < 0 ) {
 175                                 $sql .= "$field=$field-" . abs( $delta );
 176                         } else {
 177                                 $sql .= "$field=$field+" . abs( $delta );
 178                         }
 179                 }
 180         }
 181
 182         /**
 183          * @param string $type
 184          * @param string $sign ('+' or '-')
 185          * @return string
 186          */
 187         private function getTypeCacheKey( $type, $sign ) {
 188                 return wfMemcKey( 'sitestatsupdate', 'pendingdelta', $type, $sign );
 189         }
 190
 191         /**
 192          * Adjust the pending deltas for a stat type.
 193          * Each stat type has two pending counters, one for increments and decrements
 194          * @param string $type
 195          * @param int $delta Delta (positive or negative)
 196          */
 197         protected function adjustPending( $type, $delta ) {
 198                 global $wgMemc;
 199
 200                 if ( $delta < 0 ) { // decrement
 201                         $key = $this->getTypeCacheKey( $type, '-' );
 202                 } else { // increment
 203                         $key = $this->getTypeCacheKey( $type, '+' );
 204                 }
 205
 206                 $magnitude = abs( $delta );
 207                 if ( !$wgMemc->incr( $key, $magnitude ) ) { // not there?
 208                         if ( !$wgMemc->add( $key, $magnitude ) ) { // race?
 209                                 $wgMemc->incr( $key, $magnitude );
 210                         }
 211                 }
 212         }
 213
 214         /**
 215          * Get pending delta counters for each stat type
 216          * @return array Positive and negative deltas for each type
 217          */
 218         protected function getPendingDeltas() {
 219                 global $wgMemc;
 220
 221                 $pending = array();
 222                 foreach ( array( 'ss_total_edits',
 223                         'ss_good_articles', 'ss_total_pages', 'ss_users', 'ss_images' ) as $type
 224                 ) {
 225                         // Get pending increments and pending decrements
 226                         $pending[$type]['+'] = (int)$wgMemc->get( $this->getTypeCacheKey( $type, '+' ) );
 227                         $pending[$type]['-'] = (int)$wgMemc->get( $this->getTypeCacheKey( $type, '-' ) );
 228                 }
 229
 230                 return $pending;
 231         }
 232
 233         /**
 234          * Reduce pending delta counters after updates have been applied
 235          * @param array $pd Result of getPendingDeltas(), used for DB update
 236          */
 237         protected function removePendingDeltas( array $pd ) {
 238                 global $wgMemc;
 239
 240                 foreach ( $pd as $type => $deltas ) {
 241                         foreach ( $deltas as $sign => $magnitude ) {
 242                                 // Lower the pending counter now that we applied these changes
 243                                 $wgMemc->decr( $this->getTypeCacheKey( $type, $sign ), $magnitude );
 244                         }
 245                 }
 246         }
 247 }