Detect query timeouts and throw a specific exception

Throw DBQueryTimeoutError if a database query error is detected
to be a timeout.

Only DatabaseMysqlBase has been updated here.

This is a subclass of DBQueryError, so existing catch'es will work.

Bug: T175775
Change-Id: I4749dc33ad530d9b22504f02106b1ca49e8eb167

diff --git a/autoload.php b/autoload.php
index 61fd192..4dd5f12 100644 (file)
--- a/autoload.php
+++ b/autoload.php
@@ -1636,6 +1636,7 @@ $wgAutoloadLocalClasses = [
        'Wikimedia\\Rdbms\\DBExpectedError' => __DIR__ . '/includes/libs/rdbms/exception/DBExpectedError.php',
        'Wikimedia\\Rdbms\\DBMasterPos' => __DIR__ . '/includes/libs/rdbms/database/position/DBMasterPos.php',
        'Wikimedia\\Rdbms\\DBQueryError' => __DIR__ . '/includes/libs/rdbms/exception/DBQueryError.php',
+       'Wikimedia\\Rdbms\\DBQueryTimeoutError' => __DIR__ . '/includes/libs/rdbms/exception/DBQueryTimeoutError.php',
        'Wikimedia\\Rdbms\\DBReadOnlyError' => __DIR__ . '/includes/libs/rdbms/exception/DBReadOnlyError.php',
        'Wikimedia\\Rdbms\\DBReplicationWaitError' => __DIR__ . '/includes/libs/rdbms/exception/DBReplicationWaitError.php',
        'Wikimedia\\Rdbms\\DBTransactionError' => __DIR__ . '/includes/libs/rdbms/exception/DBTransactionError.php',

diff --git a/includes/libs/rdbms/database/Database.php b/includes/libs/rdbms/database/Database.php
index c904092..e7417eb 100644 (file)
--- a/includes/libs/rdbms/database/Database.php
+++ b/includes/libs/rdbms/database/Database.php
@@ -1130,6 +1130,19 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
                }
        }
 
+       /**
+        * Checks whether the cause of the error is detected to be a timeout.
+        *
+        * It returns false by default, and not all engines support detecting this yet.
+        * If this returns false, it will be treated as a generic query error.
+        *
+        * @param string $error Error text
+        * @param int $errno Error number
+        */
+       protected function wasQueryTimeout( $error, $errno ) {
+               return false;
+       }
+
        public function reportQueryError( $error, $errno, $sql, $fname, $tempIgnore = false ) {
                if ( $this->ignoreErrors() || $tempIgnore ) {
                        $this->queryLogger->debug( "SQL ERROR (ignored): $error\n" );
@@ -1146,7 +1159,12 @@ abstract class Database implements IDatabase, IMaintainableDatabase, LoggerAware
                                ] )
                        );
                        $this->queryLogger->debug( "SQL ERROR: " . $error . "\n" );
-                       throw new DBQueryError( $this, $error, $errno, $sql, $fname );
+                       $wasQueryTimeout = $this->wasQueryTimeout( $error, $errno );
+                       if ( $wasQueryTimeout ) {
+                               throw new DBQueryTimeoutError( $this, $error, $errno, $sql, $fname );
+                       } else {
+                               throw new DBQueryError( $this, $error, $errno, $sql, $fname );
+                       }
                }
        }
 

diff --git a/includes/libs/rdbms/database/DatabaseMysqlBase.php b/includes/libs/rdbms/database/DatabaseMysqlBase.php
index 3c4cda5..5312a3d 100644 (file)
--- a/includes/libs/rdbms/database/DatabaseMysqlBase.php
+++ b/includes/libs/rdbms/database/DatabaseMysqlBase.php
@@ -486,6 +486,10 @@ abstract class DatabaseMysqlBase extends Database {
         */
        abstract protected function mysqlError( $conn = null );
 
+       protected function wasQueryTimeout( $error, $errno ) {
+               return $errno == 2062;
+       }
+
        /**
         * @param string $table
         * @param array $uniqueIndexes

diff --git a/includes/libs/rdbms/exception/DBQueryError.php b/includes/libs/rdbms/exception/DBQueryError.php
index a8ea3ad..e6870a7 100644 (file)
--- a/includes/libs/rdbms/exception/DBQueryError.php
+++ b/includes/libs/rdbms/exception/DBQueryError.php
@@ -40,19 +40,22 @@ class DBQueryError extends DBExpectedError {
         * @param int|string $errno
         * @param string $sql
         * @param string $fname
+        * @param string $message Optional message, intended for subclases (optional)
         */
-       public function __construct( IDatabase $db, $error, $errno, $sql, $fname ) {
-               if ( $db instanceof Database && $db->wasConnectionError( $errno ) ) {
-                       $message = "A connection error occured. \n" .
-                               "Query: $sql\n" .
-                               "Function: $fname\n" .
-                               "Error: $errno $error\n";
-               } else {
-                       $message = "A database query error has occurred. Did you forget to run " .
-                               "your application's database schema updater after upgrading? \n" .
-                               "Query: $sql\n" .
-                               "Function: $fname\n" .
-                               "Error: $errno $error\n";
+       public function __construct( IDatabase $db, $error, $errno, $sql, $fname, $message = null ) {
+               if ( $message === null ) {
+                       if ( $db instanceof Database && $db->wasConnectionError( $errno ) ) {
+                               $message = "A connection error occured. \n" .
+                                        "Query: $sql\n" .
+                                        "Function: $fname\n" .
+                                        "Error: $errno $error\n";
+                       } else {
+                               $message = "A database query error has occurred. Did you forget to run " .
+                                        "your application's database schema updater after upgrading? \n" .
+                                        "Query: $sql\n" .
+                                        "Function: $fname\n" .
+                                        "Error: $errno $error\n";
+                       }
                }
 
                parent::__construct( $db, $message );

diff --git a/includes/libs/rdbms/exception/DBQueryTimeoutError.php b/includes/libs/rdbms/exception/DBQueryTimeoutError.php
new file mode 100644 (file)
index 0000000..ea91d95
--- /dev/null
+++ b/includes/libs/rdbms/exception/DBQueryTimeoutError.php
@@ -0,0 +1,38 @@
+<?php
+/**
+ * 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
+ * @ingroup Database
+ */
+
+namespace Wikimedia\Rdbms;
+
+/**
+ * Error thrown when a query times out
+ *
+ * @ingroup Database
+ */
+class DBQueryTimeoutError extends DBQueryError {
+       public function __construct( IDatabase $db, $error, $errno, $sql, $fname ) {
+               $message = "A database query timeout has occurred. \n" .
+                        "Query: $sql\n" .
+                        "Function: $fname\n" .
+                        "Error: $errno $error\n";
+
+               parent::__construct( $db, $error, $errno, $sql, $fname, $message );
+       }
+}