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