1 files changed, 119 insertions, 0 deletions
diff --git a/includes/deferred/ViewCountUpdate.php b/includes/deferred/ViewCountUpdate.php
new file mode 100644
index 00000000..8282295b
--- /dev/null
+++ b/includes/deferred/ViewCountUpdate.php
@@ -0,0 +1,119 @@
+<?php
+/**
+ * Update for the 'page_counter' field
+ *
+ * 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
+ */
+
+/**
+ * Update for the 'page_counter' field, when $wgDisableCounters is false.
+ *
+ * Depending on $wgHitcounterUpdateFreq, this will directly increment the
+ * 'page_counter' field or use the 'hitcounter' table and then collect the data
+ * from that table to update the 'page_counter' field in a batch operation.
+ */
+class ViewCountUpdate implements DeferrableUpdate {
+	/** @var int Page ID to increment the view count */
+	protected $id;
+
+	/**
+	 * Constructor
+	 *
+	 * @param int $id Page ID to increment the view count
+	 */
+	public function __construct( $id ) {
+		$this->id = intval( $id );
+	}
+
+	/**
+	 * Run the update
+	 */
+	public function doUpdate() {
+		global $wgHitcounterUpdateFreq;
+
+		$dbw = wfGetDB( DB_MASTER );
+
+		if ( $wgHitcounterUpdateFreq <= 1 || $dbw->getType() == 'sqlite' ) {
+			$id = $this->id;
+			$method = __METHOD__;
+			$dbw->onTransactionIdle( function () use ( $dbw, $id, $method ) {
+				try {
+					$dbw->update( 'page',
+						array( 'page_counter = page_counter + 1' ),
+						array( 'page_id' => $id ),
+						$method
+					);
+				} catch ( DBError $e ) {
+					MWExceptionHandler::logException( $e );
+				}
+			} );
+			return;
+		}
+
+		# Not important enough to warrant an error page in case of failure
+		try {
+			// Since `hitcounter` is non-transactional, the contention is minimal
+			$dbw->insert( 'hitcounter', array( 'hc_id' => $this->id ), __METHOD__ );
+			$checkfreq = intval( $wgHitcounterUpdateFreq / 25 + 1 );
+			if ( rand() % $checkfreq == 0 && $dbw->lastErrno() == 0 ) {
+				$this->collect();
+			}
+		} catch ( DBError $e ) {
+			MWExceptionHandler::logException( $e );
+		}
+	}
+
+	protected function collect() {
+		global $wgHitcounterUpdateFreq;
+
+		$dbw = wfGetDB( DB_MASTER );
+
+		$rown = $dbw->selectField( 'hitcounter', 'COUNT(*)', array(), __METHOD__ );
+		if ( $rown < $wgHitcounterUpdateFreq ) {
+			return;
+		}
+
+		wfProfileIn( __METHOD__ . '-collect' );
+		$old_user_abort = ignore_user_abort( true );
+
+		$dbType = $dbw->getType();
+		$tabletype = $dbType == 'mysql' ? "ENGINE=HEAP " : '';
+		$hitcounterTable = $dbw->tableName( 'hitcounter' );
+		$acchitsTable = $dbw->tableName( 'acchits' );
+		$pageTable = $dbw->tableName( 'page' );
+
+		$dbw->lockTables( array(), array( 'hitcounter' ), __METHOD__, false );
+		$dbw->query( "CREATE TEMPORARY TABLE $acchitsTable $tabletype AS " .
+			"SELECT hc_id,COUNT(*) AS hc_n FROM $hitcounterTable " .
+			'GROUP BY hc_id', __METHOD__ );
+		$dbw->delete( 'hitcounter', '*', __METHOD__ );
+		$dbw->unlockTables( __METHOD__ );
+
+		if ( $dbType == 'mysql' ) {
+			$dbw->query( "UPDATE $pageTable,$acchitsTable SET page_counter=page_counter + hc_n " .
+				'WHERE page_id = hc_id', __METHOD__ );
+		} else {
+			$dbw->query( "UPDATE $pageTable SET page_counter=page_counter + hc_n " .
+				"FROM $acchitsTable WHERE page_id = hc_id", __METHOD__ );
+		}
+		$dbw->query( "DROP TABLE $acchitsTable", __METHOD__ );
+
+		ignore_user_abort( $old_user_abort );
+		wfProfileOut( __METHOD__ . '-collect' );
+	}
+}