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 $views = 0;
  27
  28         /** @var int */
  29         protected $edits = 0;
  30
  31         /** @var int */
  32         protected $pages = 0;
  33
  34         /** @var int */
  35         protected $articles = 0;
  36
  37         /** @var int */
  38         protected $users = 0;
  39
  40         /** @var int */
  41         protected $images = 0;
  42
  43         // @todo deprecate this constructor
  44         function __construct( $views, $edits, $good, $pages = 0, $users = 0 ) {
  45                 $this->views = $views;
  46                 $this->edits = $edits;
  47                 $this->articles = $good;
  48                 $this->pages = $pages;
  49                 $this->users = $users;
  50         }
  51
  52         /**
  53          * @param array $deltas
  54          * @return SiteStatsUpdate
  55          */
  56         public static function factory( array $deltas ) {
  57                 $update = new self( 0, 0, 0 );
  58
  59                 $fields = array( 'views', 'edits', 'pages', 'articles', 'users', 'images' );
  60                 foreach ( $fields as $field ) {
  61                         if ( isset( $deltas[$field] ) && $deltas[$field] ) {
  62                                 $update->$field = $deltas[$field];
  63                         }
  64                 }
  65
  66                 return $update;
  67         }
  68
  69         public function doUpdate() {
  70                 global $wgSiteStatsAsyncFactor;
  71
  72                 $rate = $wgSiteStatsAsyncFactor; // convenience
  73                 // If set to do so, only do actual DB updates 1 every $rate times.
  74                 // The other times, just update "pending delta" values in memcached.
  75                 if ( $rate && ( $rate < 0 || mt_rand( 0, $rate - 1 ) != 0 ) ) {
  76                         $this->doUpdatePendingDeltas();
  77                 } else {
  78                         // Need a separate transaction because this a global lock
  79                         wfGetDB( DB_MASTER )->onTransactionIdle( array( $this, 'tryDBUpdateInternal' ) );
  80                 }
  81         }
  82
  83         /**
  84          * Do not call this outside of SiteStatsUpdate
  85          */
  86         public function tryDBUpdateInternal() {
  87                 global $wgSiteStatsAsyncFactor;
  88
  89                 $dbw = wfGetDB( DB_MASTER );
  90                 $lockKey = wfMemcKey( 'site_stats' ); // prepend wiki ID
  91                 $pd = array();
  92                 if ( $wgSiteStatsAsyncFactor ) {
  93                         // Lock the table so we don't have double DB/memcached updates
  94                         if ( !$dbw->lockIsFree( $lockKey, __METHOD__ )
  95                                 || !$dbw->lock( $lockKey, __METHOD__, 1 ) // 1 sec timeout
  96                         ) {
  97                                 $this->doUpdatePendingDeltas();
  98
  99                                 return;
 100                         }
 101                         $pd = $this->getPendingDeltas();
 102                         // Piggy-back the async deltas onto those of this stats update....
 103                         $this->views += ( $pd['ss_total_views']['+'] - $pd['ss_total_views']['-'] );
 104                         $this->edits += ( $pd['ss_total_edits']['+'] - $pd['ss_total_edits']['-'] );
 105                         $this->articles += ( $pd['ss_good_articles']['+'] - $pd['ss_good_articles']['-'] );
 106                         $this->pages += ( $pd['ss_total_pages']['+'] - $pd['ss_total_pages']['-'] );
 107                         $this->users += ( $pd['ss_users']['+'] - $pd['ss_users']['-'] );
 108                         $this->images += ( $pd['ss_images']['+'] - $pd['ss_images']['-'] );
 109                 }
 110
 111                 // Build up an SQL query of deltas and apply them...
 112                 $updates = '';
 113                 $this->appendUpdate( $updates, 'ss_total_views', $this->views );
 114                 $this->appendUpdate( $updates, 'ss_total_edits', $this->edits );
 115                 $this->appendUpdate( $updates, 'ss_good_articles', $this->articles );
 116                 $this->appendUpdate( $updates, 'ss_total_pages', $this->pages );
 117                 $this->appendUpdate( $updates, 'ss_users', $this->users );
 118                 $this->appendUpdate( $updates, 'ss_images', $this->images );
 119                 if ( $updates != '' ) {
 120                         $dbw->update( 'site_stats', array( $updates ), array(), __METHOD__ );
 121                 }
 122
 123                 if ( $wgSiteStatsAsyncFactor ) {
 124                         // Decrement the async deltas now that we applied them
 125                         $this->removePendingDeltas( $pd );
 126                         // Commit the updates and unlock the table
 127                         $dbw->unlock( $lockKey, __METHOD__ );
 128                 }
 129         }
 130
 131         /**
 132          * @param DatabaseBase $dbw
 133          * @return bool|mixed
 134          */
 135         public static function cacheUpdate( $dbw ) {
 136                 global $wgActiveUserDays;
 137                 $dbr = wfGetDB( DB_SLAVE, array( 'SpecialStatistics', 'vslow' ) );
 138                 # Get non-bot users than did some recent action other than making accounts.
 139                 # If account creation is included, the number gets inflated ~20+ fold on enwiki.
 140                 $activeUsers = $dbr->selectField(
 141                         'recentchanges',
 142                         'COUNT( DISTINCT rc_user_text )',
 143                         array(
 144                                 'rc_user != 0',
 145                                 'rc_bot' => 0,
 146                                 'rc_log_type != ' . $dbr->addQuotes( 'newusers' ) . ' OR rc_log_type IS NULL',
 147                                 'rc_timestamp >= ' . $dbr->addQuotes( $dbr->timestamp( wfTimestamp( TS_UNIX )
 148                                         - $wgActiveUserDays * 24 * 3600 ) ),
 149                         ),
 150                         __METHOD__
 151                 );
 152                 $dbw->update(
 153                         'site_stats',
 154                         array( 'ss_active_users' => intval( $activeUsers ) ),
 155                         array( 'ss_row_id' => 1 ),
 156                         __METHOD__
 157                 );
 158
 159                 return $activeUsers;
 160         }
 161
 162         protected function doUpdatePendingDeltas() {
 163                 $this->adjustPending( 'ss_total_views', $this->views );
 164                 $this->adjustPending( 'ss_total_edits', $this->edits );
 165                 $this->adjustPending( 'ss_good_articles', $this->articles );
 166                 $this->adjustPending( 'ss_total_pages', $this->pages );
 167                 $this->adjustPending( 'ss_users', $this->users );
 168                 $this->adjustPending( 'ss_images', $this->images );
 169         }
 170
 171         /**
 172          * @param string $sql
 173          * @param string $field
 174          * @param int $delta
 175          */
 176         protected function appendUpdate( &$sql, $field, $delta ) {
 177                 if ( $delta ) {
 178                         if ( $sql ) {
 179                                 $sql .= ',';
 180                         }
 181                         if ( $delta < 0 ) {
 182                                 $sql .= "$field=$field-" . abs( $delta );
 183                         } else {
 184                                 $sql .= "$field=$field+" . abs( $delta );
 185                         }
 186                 }
 187         }
 188
 189         /**
 190          * @param string $type
 191          * @param string $sign ('+' or '-')
 192          * @return string
 193          */
 194         private function getTypeCacheKey( $type, $sign ) {
 195                 return wfMemcKey( 'sitestatsupdate', 'pendingdelta', $type, $sign );
 196         }
 197
 198         /**
 199          * Adjust the pending deltas for a stat type.
 200          * Each stat type has two pending counters, one for increments and decrements
 201          * @param string $type
 202          * @param int $delta Delta (positive or negative)
 203          */
 204         protected function adjustPending( $type, $delta ) {
 205                 global $wgMemc;
 206
 207                 if ( $delta < 0 ) { // decrement
 208                         $key = $this->getTypeCacheKey( $type, '-' );
 209                 } else { // increment
 210                         $key = $this->getTypeCacheKey( $type, '+' );
 211                 }
 212
 213                 $magnitude = abs( $delta );
 214                 if ( !$wgMemc->incr( $key, $magnitude ) ) { // not there?
 215                         if ( !$wgMemc->add( $key, $magnitude ) ) { // race?
 216                                 $wgMemc->incr( $key, $magnitude );
 217                         }
 218                 }
 219         }
 220
 221         /**
 222          * Get pending delta counters for each stat type
 223          * @return array Positive and negative deltas for each type
 224          */
 225         protected function getPendingDeltas() {
 226                 global $wgMemc;
 227
 228                 $pending = array();
 229                 foreach ( array( 'ss_total_views', 'ss_total_edits',
 230                         'ss_good_articles', 'ss_total_pages', 'ss_users', 'ss_images' ) as $type
 231                 ) {
 232                         // Get pending increments and pending decrements
 233                         $pending[$type]['+'] = (int)$wgMemc->get( $this->getTypeCacheKey( $type, '+' ) );
 234                         $pending[$type]['-'] = (int)$wgMemc->get( $this->getTypeCacheKey( $type, '-' ) );
 235                 }
 236
 237                 return $pending;
 238         }
 239
 240         /**
 241          * Reduce pending delta counters after updates have been applied
 242          * @param array $pd Result of getPendingDeltas(), used for DB update
 243          */
 244         protected function removePendingDeltas( array $pd ) {
 245                 global $wgMemc;
 246
 247                 foreach ( $pd as $type => $deltas ) {
 248                         foreach ( $deltas as $sign => $magnitude ) {
 249                                 // Lower the pending counter now that we applied these changes
 250                                 $wgMemc->decr( $this->getTypeCacheKey( $type, $sign ), $magnitude );
 251                         }
 252                 }
 253         }
 254 }