SessionProvider::mergeMetadata: Log additional data

Add the data values and types to the exception raised when mismatched
session data is processed. This is done by passing the old and new
values on via a new MetadataMergeException class. The attached data is
added to the debug logging context info when caught.

Change-Id: If8a7174399289bc284ca1b36052ba515c8857c50

diff --git a/autoload.php b/autoload.php
index d6e4077..ab6c5e0 100644 (file)
--- a/autoload.php
+++ b/autoload.php
@@ -796,6 +796,7 @@ $wgAutoloadLocalClasses = array(
        'MediaWiki\\Session\\BotPasswordSessionProvider' => __DIR__ . '/includes/session/BotPasswordSessionProvider.php',
        'MediaWiki\\Session\\CookieSessionProvider' => __DIR__ . '/includes/session/CookieSessionProvider.php',
        'MediaWiki\\Session\\ImmutableSessionProviderWithCookie' => __DIR__ . '/includes/session/ImmutableSessionProviderWithCookie.php',
+       'MediaWiki\\Session\\MetadataMergeException' => __DIR__ . '/includes/session/MetadataMergeException.php',
        'MediaWiki\\Session\\PHPSessionHandler' => __DIR__ . '/includes/session/PHPSessionHandler.php',
        'MediaWiki\\Session\\Session' => __DIR__ . '/includes/session/Session.php',
        'MediaWiki\\Session\\SessionBackend' => __DIR__ . '/includes/session/SessionBackend.php',

diff --git a/includes/session/MetadataMergeException.php b/includes/session/MetadataMergeException.php
new file mode 100644 (file)
index 0000000..9f42c27
--- /dev/null
+++ b/includes/session/MetadataMergeException.php
@@ -0,0 +1,70 @@
+<?php
+/**
+ * @section LICENSE
+ * 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 Session
+ */
+
+namespace MediaWiki\Session;
+
+use UnexpectedValueException;
+
+/**
+ * Subclass of UnexpectedValueException that can be annotated with additional
+ * data for debug logging.
+ *
+ * @author Bryan Davis <bd808@wikimedia.org>
+ * @copyright © 2016 Bryan Davis and Wikimedia Foundation.
+ * @since 1.27
+ */
+class MetadataMergeException extends UnexpectedValueException {
+       /** @var array $context */
+       protected $context;
+
+       /**
+        * @param string $message
+        * @param int $code
+        * @param Exception|null $previous
+        * @param array $context Additional context data
+        */
+       public function __construct(
+               $message = '',
+               $code = 0,
+               Exception $previous = null,
+               array $context = []
+       ) {
+               parent::__construct( $message, $code, $previous );
+               $this->context = $context;
+       }
+
+       /**
+        * Get context data.
+        * @return array
+        */
+       public function getContext() {
+               return $this->context;
+       }
+
+       /**
+        * Set context data.
+        * @param array $context
+        */
+       public function setContext( array $context ) {
+               $this->context = $context;
+       }
+}

diff --git a/includes/session/SessionManager.php b/includes/session/SessionManager.php
index 83c30ab..6e4f99c 100644 (file)
--- a/includes/session/SessionManager.php
+++ b/includes/session/SessionManager.php
@@ -744,13 +744,14 @@ final class SessionManager implements SessionManagerInterface {
                                                if ( $newProviderMetadata !== $providerMetadata ) {
                                                        $newParams['metadata'] = $newProviderMetadata;
                                                }
-                                       } catch ( \UnexpectedValueException $ex ) {
+                                       } catch ( MetadataMergeException $ex ) {
                                                $this->logger->warning(
                                                        'Session "{session}": Metadata merge failed: {exception}',
                                                        array(
                                                                'session' => $info,
                                                                'exception' => $ex,
-                                               ) );
+                                                       ) + $ex->getContext()
+                                               );
                                                return false;
                                        }
                                }

diff --git a/includes/session/SessionProvider.php b/includes/session/SessionProvider.php
index 0fd3a71..db6294d 100644 (file)
--- a/includes/session/SessionProvider.php
+++ b/includes/session/SessionProvider.php
@@ -186,12 +186,17 @@ abstract class SessionProvider implements SessionProviderInterface, LoggerAwareI
         * @param array $savedMetadata Saved provider metadata
         * @param array $providedMetadata Provided provider metadata
         * @return array Resulting metadata
-        * @throws \UnexpectedValueException If the metadata cannot be merged
+        * @throws MetadataMergeException If the metadata cannot be merged
         */
        public function mergeMetadata( array $savedMetadata, array $providedMetadata ) {
                foreach ( $providedMetadata as $k => $v ) {
                        if ( array_key_exists( $k, $savedMetadata ) && $savedMetadata[$k] !== $v ) {
-                               throw new \UnexpectedValueException( "Key \"$k\" changed" );
+                               $e = new MetadataMergeException( "Key \"$k\" changed" );
+                               $e->setContext( [
+                                       'old_value' => $savedMetadata[$k],
+                                       'new_value' => $v,
+                               ] );
+                               throw $e;
                        }
                }
                return $providedMetadata;

diff --git a/tests/phpunit/includes/session/SessionManagerTest.php b/tests/phpunit/includes/session/SessionManagerTest.php
index 16beb72..94bf184 100644 (file)
--- a/tests/phpunit/includes/session/SessionManagerTest.php
+++ b/tests/phpunit/includes/session/SessionManagerTest.php
@@ -1112,7 +1112,7 @@ class SessionManagerTest extends MediaWikiTestCase {
                $provider->expects( $this->any() )->method( 'mergeMetadata' )
                        ->will( $this->returnCallback( function ( $a, $b ) {
                                if ( $b === array( 'Throw' ) ) {
-                                       throw new \UnexpectedValueException( 'no merge!' );
+                                       throw new MetadataMergeException( 'no merge!' );
                                }
                                return array( 'Merged' );
                        } ) );

diff --git a/tests/phpunit/includes/session/SessionProviderTest.php b/tests/phpunit/includes/session/SessionProviderTest.php
index d7aebcd..7d9004a 100644 (file)
--- a/tests/phpunit/includes/session/SessionProviderTest.php
+++ b/tests/phpunit/includes/session/SessionProviderTest.php
@@ -89,8 +89,10 @@ class SessionProviderTest extends MediaWikiTestCase {
                                array( 'bar' => 2, 'baz' => '3' )
                        );
                        $this->fail( 'Expected exception not thrown' );
-               } catch ( \UnexpectedValueException $ex ) {
+               } catch ( MetadataMergeException $ex ) {
                        $this->assertSame( 'Key "baz" changed', $ex->getMessage() );
+                       $this->assertSame(
+                               [ 'old_value' => 3, 'new_value' => '3' ], $ex->getContext() );
                }
 
                $res = $provider->mergeMetadata(