includes/SiteStats.php

   1 <?php
   2 /**
   3  * Accessors and mutators for the site-wide statistics.
   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  */
  22
  23 use Wikimedia\Rdbms\Database;
  24 use Wikimedia\Rdbms\IDatabase;
  25 use MediaWiki\MediaWikiServices;
  26 use Wikimedia\Rdbms\LoadBalancer;
  27
  28 /**
  29  * Static accessor class for site_stats and related things
  30  */
  31 class SiteStats {
  32         /** @var stdClass */
  33         private static $row;
  34
  35         /**
  36          * Trigger a reload next time a field is accessed
  37          */
  38         public static function unload() {
  39                 self::$row = null;
  40         }
  41
  42         protected static function load() {
  43                 if ( self::$row === null ) {
  44                         self::$row = self::loadAndLazyInit();
  45                 }
  46         }
  47
  48         /**
  49          * @return stdClass
  50          */
  51         protected static function loadAndLazyInit() {
  52                 $config = MediaWikiServices::getInstance()->getMainConfig();
  53
  54                 $lb = self::getLB();
  55                 $dbr = $lb->getConnection( DB_REPLICA );
  56                 wfDebug( __METHOD__ . ": reading site_stats from replica DB\n" );
  57                 $row = self::doLoadFromDB( $dbr );
  58
  59                 if ( !self::isRowSane( $row ) && $lb->hasOrMadeRecentMasterChanges() ) {
  60                         // Might have just been initialized during this request? Underflow?
  61                         wfDebug( __METHOD__ . ": site_stats damaged or missing on replica DB\n" );
  62                         $row = self::doLoadFromDB( $lb->getConnection( DB_MASTER ) );
  63                 }
  64
  65                 if ( !self::isRowSane( $row ) ) {
  66                         if ( $config->get( 'MiserMode' ) ) {
  67                                 // Start off with all zeroes, assuming that this is a new wiki or any
  68                                 // repopulations where done manually via script.
  69                                 SiteStatsInit::doPlaceholderInit();
  70                         } else {
  71                                 // Normally the site_stats table is initialized at install time.
  72                                 // Some manual construction scenarios may leave the table empty or
  73                                 // broken, however, for instance when importing from a dump into a
  74                                 // clean schema with mwdumper.
  75                                 wfDebug( __METHOD__ . ": initializing damaged or missing site_stats\n" );
  76                                 SiteStatsInit::doAllAndCommit( $dbr );
  77                         }
  78
  79                         $row = self::doLoadFromDB( $lb->getConnection( DB_MASTER ) );
  80                 }
  81
  82                 if ( !self::isRowSane( $row ) ) {
  83                         wfDebug( __METHOD__ . ": site_stats persistently nonsensical o_O\n" );
  84                         // Always return a row-like object
  85                         $row = self::salvageInsaneRow( $row );
  86                 }
  87
  88                 return $row;
  89         }
  90
  91         /**
  92          * @return int
  93          */
  94         public static function edits() {
  95                 self::load();
  96
  97                 return (int)self::$row->ss_total_edits;
  98         }
  99
 100         /**
 101          * @return int
 102          */
 103         public static function articles() {
 104                 self::load();
 105
 106                 return (int)self::$row->ss_good_articles;
 107         }
 108
 109         /**
 110          * @return int
 111          */
 112         public static function pages() {
 113                 self::load();
 114
 115                 return (int)self::$row->ss_total_pages;
 116         }
 117
 118         /**
 119          * @return int
 120          */
 121         public static function users() {
 122                 self::load();
 123
 124                 return (int)self::$row->ss_users;
 125         }
 126
 127         /**
 128          * @return int
 129          */
 130         public static function activeUsers() {
 131                 self::load();
 132
 133                 return (int)self::$row->ss_active_users;
 134         }
 135
 136         /**
 137          * @return int
 138          */
 139         public static function images() {
 140                 self::load();
 141
 142                 return (int)self::$row->ss_images;
 143         }
 144
 145         /**
 146          * Find the number of users in a given user group.
 147          * @param string $group Name of group
 148          * @return int
 149          */
 150         public static function numberingroup( $group ) {
 151                 $cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
 152
 153                 return $cache->getWithSetCallback(
 154                         $cache->makeKey( 'SiteStats', 'groupcounts', $group ),
 155                         $cache::TTL_HOUR,
 156                         function ( $oldValue, &$ttl, array &$setOpts ) use ( $group ) {
 157                                 $dbr = self::getLB()->getConnection( DB_REPLICA );
 158                                 $setOpts += Database::getCacheSetOptions( $dbr );
 159
 160                                 return (int)$dbr->selectField(
 161                                         'user_groups',
 162                                         'COUNT(*)',
 163                                         [
 164                                                 'ug_group' => $group,
 165                                                 'ug_expiry IS NULL OR ug_expiry >= ' . $dbr->addQuotes( $dbr->timestamp() )
 166                                         ],
 167                                         __METHOD__
 168                                 );
 169                         },
 170                         [ 'pcTTL' => $cache::TTL_PROC_LONG ]
 171                 );
 172         }
 173
 174         /**
 175          * Total number of jobs in the job queue.
 176          * @return int
 177          */
 178         public static function jobs() {
 179                 $cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
 180
 181                 return $cache->getWithSetCallback(
 182                         $cache->makeKey( 'SiteStats', 'jobscount' ),
 183                         $cache::TTL_MINUTE,
 184                         function ( $oldValue, &$ttl, array &$setOpts ) {
 185                                 try{
 186                                         $jobs = array_sum( JobQueueGroup::singleton()->getQueueSizes() );
 187                                 } catch ( JobQueueError $e ) {
 188                                         $jobs = 0;
 189                                 }
 190                                 return $jobs;
 191                         },
 192                         [ 'pcTTL' => $cache::TTL_PROC_LONG ]
 193                 );
 194         }
 195
 196         /**
 197          * @param int $ns
 198          * @return int
 199          */
 200         public static function pagesInNs( $ns ) {
 201                 $cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
 202
 203                 return $cache->getWithSetCallback(
 204                         $cache->makeKey( 'SiteStats', 'page-in-namespace', $ns ),
 205                         $cache::TTL_HOUR,
 206                         function ( $oldValue, &$ttl, array &$setOpts ) use ( $ns ) {
 207                                 $dbr = self::getLB()->getConnection( DB_REPLICA );
 208                                 $setOpts += Database::getCacheSetOptions( $dbr );
 209
 210                                 return (int)$dbr->selectField(
 211                                         'page',
 212                                         'COUNT(*)',
 213                                         [ 'page_namespace' => $ns ],
 214                                         __METHOD__
 215                                 );
 216                         },
 217                         [ 'pcTTL' => $cache::TTL_PROC_LONG ]
 218                 );
 219         }
 220
 221         /**
 222          * @return array
 223          */
 224         public static function selectFields() {
 225                 return [
 226                         'ss_total_edits',
 227                         'ss_good_articles',
 228                         'ss_total_pages',
 229                         'ss_users',
 230                         'ss_active_users',
 231                         'ss_images',
 232                 ];
 233         }
 234
 235         /**
 236          * @param IDatabase $db
 237          * @return stdClass|bool
 238          */
 239         private static function doLoadFromDB( IDatabase $db ) {
 240                 return $db->selectRow(
 241                         'site_stats',
 242                         self::selectFields(),
 243                         [ 'ss_row_id' => 1 ],
 244                         __METHOD__
 245                 );
 246         }
 247
 248         /**
 249          * Is the provided row of site stats sane, or should it be regenerated?
 250          *
 251          * Checks only fields which are filled by SiteStatsInit::refresh.
 252          *
 253          * @param bool|object $row
 254          * @return bool
 255          */
 256         private static function isRowSane( $row ) {
 257                 if ( $row === false
 258                         || $row->ss_total_pages < $row->ss_good_articles
 259                         || $row->ss_total_edits < $row->ss_total_pages
 260                 ) {
 261                         return false;
 262                 }
 263                 // Now check for underflow/overflow
 264                 foreach ( [
 265                         'ss_total_edits',
 266                         'ss_good_articles',
 267                         'ss_total_pages',
 268                         'ss_users',
 269                         'ss_images',
 270                 ] as $member ) {
 271                         if ( $row->$member < 0 ) {
 272                                 return false;
 273                         }
 274                 }
 275
 276                 return true;
 277         }
 278
 279         /**
 280          * @param stdClass|bool $row
 281          * @return stdClass
 282          */
 283         private static function salvageInsaneRow( $row ) {
 284                 $map = $row ? (array)$row : [];
 285                 // Fill in any missing values with zero
 286                 $map += array_fill_keys( self::selectFields(), 0 );
 287                 // Convert negative values to zero
 288                 foreach ( $map as $field => $value ) {
 289                         $map[$field] = max( 0, $value );
 290                 }
 291
 292                 return (object)$row;
 293         }
 294
 295         /**
 296          * @return LoadBalancer
 297          */
 298         private static function getLB() {
 299                 return MediaWikiServices::getInstance()->getDBLoadBalancer();
 300         }
 301 }