Reorg: Move SiteStats*.php to SiteStats/

It's going to be a bit small and narrow but it's better than sitting in
the root of includes/ plus I hope we can hollow out SiteStatsUpdate
class into the third one and or move this under a better directory in
the future.

Bug: T321882
Change-Id: Ia503b53b31ca00600f8c18b61a2652c3e146494e

1 files changed, 303 insertions, 0 deletions

diff --git a/includes/SiteStats/SiteStats.php b/includes/SiteStats/SiteStats.php
new file mode 100644
index 000000000000..dfb93ab316c5
--- /dev/null
+++ b/includes/SiteStats/SiteStats.php
@@ -0,0 +1,303 @@
+<?php
+/**
+ * Accessors and mutators for the site-wide statistics.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ */
+
+namespace MediaWiki\SiteStats;
+
+use JobQueueError;
+use MediaWiki\MainConfigNames;
+use MediaWiki\MediaWikiServices;
+use stdClass;
+use Wikimedia\Rdbms\Database;
+use Wikimedia\Rdbms\IDatabase;
+use Wikimedia\Rdbms\ILoadBalancer;
+
+/**
+ * Static accessor class for site_stats and related things
+ */
+class SiteStats {
+	/** @var stdClass|null */
+	private static $row;
+
+	/**
+	 * Trigger a reload next time a field is accessed
+	 */
+	public static function unload() {
+		self::$row = null;
+	}
+
+	protected static function load() {
+		if ( self::$row === null ) {
+			self::$row = self::loadAndLazyInit();
+		}
+	}
+
+	/**
+	 * @return stdClass
+	 */
+	protected static function loadAndLazyInit() {
+		$config = MediaWikiServices::getInstance()->getMainConfig();
+
+		$lb = self::getLB();
+		$dbr = $lb->getConnectionRef( DB_REPLICA );
+		wfDebug( __METHOD__ . ": reading site_stats from replica DB" );
+		$row = self::doLoadFromDB( $dbr );
+
+		if ( !self::isRowSensible( $row ) && $lb->hasOrMadeRecentPrimaryChanges() ) {
+			// Might have just been initialized during this request? Underflow?
+			wfDebug( __METHOD__ . ": site_stats damaged or missing on replica DB" );
+			$row = self::doLoadFromDB( $lb->getConnectionRef( DB_PRIMARY ) );
+		}
+
+		if ( !self::isRowSensible( $row ) ) {
+			if ( $config->get( MainConfigNames::MiserMode ) ) {
+				// Start off with all zeroes, assuming that this is a new wiki or any
+				// repopulations where done manually via script.
+				SiteStatsInit::doPlaceholderInit();
+			} else {
+				// Normally the site_stats table is initialized at install time.
+				// Some manual construction scenarios may leave the table empty or
+				// broken, however, for instance when importing from a dump into a
+				// clean schema with mwdumper.
+				wfDebug( __METHOD__ . ": initializing damaged or missing site_stats" );
+				SiteStatsInit::doAllAndCommit( $dbr );
+			}
+
+			$row = self::doLoadFromDB( $lb->getConnectionRef( DB_PRIMARY ) );
+		}
+
+		return $row;
+	}
+
+	/**
+	 * @return int
+	 */
+	public static function edits() {
+		self::load();
+
+		return (int)self::$row->ss_total_edits;
+	}
+
+	/**
+	 * @return int
+	 */
+	public static function articles() {
+		self::load();
+
+		return (int)self::$row->ss_good_articles;
+	}
+
+	/**
+	 * @return int
+	 */
+	public static function pages() {
+		self::load();
+
+		return (int)self::$row->ss_total_pages;
+	}
+
+	/**
+	 * @return int
+	 */
+	public static function users() {
+		self::load();
+
+		return (int)self::$row->ss_users;
+	}
+
+	/**
+	 * @return int
+	 */
+	public static function activeUsers() {
+		self::load();
+
+		return (int)self::$row->ss_active_users;
+	}
+
+	/**
+	 * @return int
+	 */
+	public static function images() {
+		self::load();
+
+		return (int)self::$row->ss_images;
+	}
+
+	/**
+	 * Find the number of users in a given user group.
+	 * @param string $group Name of group
+	 * @return int
+	 */
+	public static function numberingroup( $group ) {
+		$cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
+		$fname = __METHOD__;
+
+		return $cache->getWithSetCallback(
+			$cache->makeKey( 'SiteStats', 'groupcounts', $group ),
+			$cache::TTL_HOUR,
+			function ( $oldValue, &$ttl, array &$setOpts ) use ( $group, $fname ) {
+				$dbr = self::getLB()->getConnectionRef( DB_REPLICA );
+				$setOpts += Database::getCacheSetOptions( $dbr );
+				return (int)$dbr->newSelectQueryBuilder()
+					->select( 'COUNT(*)' )
+					->from( 'user_groups' )
+					->where(
+						[
+							'ug_group' => $group,
+							'ug_expiry IS NULL OR ug_expiry >= ' . $dbr->addQuotes( $dbr->timestamp() )
+						]
+					)
+					->caller( $fname )
+					->fetchField();
+			},
+			[ 'pcTTL' => $cache::TTL_PROC_LONG ]
+		);
+	}
+
+	/**
+	 * Total number of jobs in the job queue.
+	 * @return int
+	 */
+	public static function jobs() {
+		$cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
+
+		return $cache->getWithSetCallback(
+			$cache->makeKey( 'SiteStats', 'jobscount' ),
+			$cache::TTL_MINUTE,
+			static function ( $oldValue, &$ttl, array &$setOpts ) {
+				try {
+					$jobs = array_sum( MediaWikiServices::getInstance()->getJobQueueGroup()->getQueueSizes() );
+				} catch ( JobQueueError $e ) {
+					$jobs = 0;
+				}
+				return $jobs;
+			},
+			[ 'pcTTL' => $cache::TTL_PROC_LONG ]
+		);
+	}
+
+	/**
+	 * @param int $ns
+	 * @return int
+	 */
+	public static function pagesInNs( $ns ) {
+		$cache = MediaWikiServices::getInstance()->getMainWANObjectCache();
+		$fname = __METHOD__;
+
+		return $cache->getWithSetCallback(
+			$cache->makeKey( 'SiteStats', 'page-in-namespace', $ns ),
+			$cache::TTL_HOUR,
+			function ( $oldValue, &$ttl, array &$setOpts ) use ( $ns, $fname ) {
+				$dbr = self::getLB()->getConnectionRef( DB_REPLICA );
+				$setOpts += Database::getCacheSetOptions( $dbr );
+
+				return (int)$dbr->selectField(
+					'page',
+					'COUNT(*)',
+					[ 'page_namespace' => $ns ],
+					$fname
+				);
+			},
+			[ 'pcTTL' => $cache::TTL_PROC_LONG ]
+		);
+	}
+
+	/**
+	 * @return array
+	 */
+	public static function selectFields() {
+		return [
+			'ss_total_edits',
+			'ss_good_articles',
+			'ss_total_pages',
+			'ss_users',
+			'ss_active_users',
+			'ss_images',
+		];
+	}
+
+	/**
+	 * @param IDatabase $db
+	 * @return stdClass|false
+	 */
+	private static function doLoadFromDB( IDatabase $db ) {
+		$fields = self::selectFields();
+		$rows = $db->newSelectQueryBuilder()
+			->select( $fields )
+			->from( 'site_stats' )
+			->caller( __METHOD__ )
+			->fetchResultSet();
+		if ( !$rows->numRows() ) {
+			return false;
+		}
+		$finalRow = new stdClass();
+		foreach ( $rows as $row ) {
+			foreach ( $fields as $field ) {
+				$finalRow->$field ??= 0;
+				if ( $row->$field ) {
+					$finalRow->$field += $row->$field;
+				}
+			}
+
+		}
+		return $finalRow;
+	}
+
+	/**
+	 * Is the provided row of site stats sensible, or should it be regenerated?
+	 *
+	 * Checks only fields which are filled by SiteStatsInit::refresh.
+	 *
+	 * @param stdClass|false $row
+	 * @return bool
+	 */
+	private static function isRowSensible( $row ) {
+		if ( $row === false
+			|| $row->ss_total_pages < $row->ss_good_articles
+			|| $row->ss_total_edits < $row->ss_total_pages
+		) {
+			return false;
+		}
+		// Now check for underflow/overflow
+		foreach ( [
+			'ss_total_edits',
+			'ss_good_articles',
+			'ss_total_pages',
+			'ss_users',
+			'ss_images',
+		] as $member ) {
+			if ( $row->$member < 0 ) {
+				return false;
+			}
+		}
+
+		return true;
+	}
+
+	/**
+	 * @return ILoadBalancer
+	 */
+	private static function getLB() {
+		return MediaWikiServices::getInstance()->getDBLoadBalancer();
+	}
+}
+
+class_alias( SiteStats::class, 'SiteStats' );