AndyRussG has uploaded a new change for review. https://gerrit.wikimedia.org/r/308126
Change subject: Account for DB lag when refreshing cached ChoiceData ...................................................................... Account for DB lag when refreshing cached ChoiceData This fixes an apparent race condition in which ObjectCache cached ChoiceData is invalidated following a change in campaign or banner settings, then a client request causes a cache miss and the cache is re-set using a laggy DB slave, causing the caching and serving of old ChoiceData. See https://github.com/wikimedia/mediawiki/blob/ce504f2d19b7450c75f0a332089a720e2ea402ce/ includes/libs/objectcache/WANObjectCache.php#L665 Bug: T144393 Change-Id: Id4e46b653554d39ac5721c4327774ccfce63b734 --- M includes/ChoiceDataProvider.php 1 file changed, 12 insertions(+), 4 deletions(-) git pull ssh://gerrit.wikimedia.org:29418/mediawiki/extensions/CentralNotice refs/changes/26/308126/1 diff --git a/includes/ChoiceDataProvider.php b/includes/ChoiceDataProvider.php index 0d765fb..0f7dd91 100644 --- a/includes/ChoiceDataProvider.php +++ b/includes/ChoiceDataProvider.php @@ -42,8 +42,17 @@ $choices = $cache->getWithSetCallback( $dataKey, self::CACHE_TTL, - function () use ( $project, $language ) { - return self::fetchChoices( $project, $language ); + function ( $oldValue, &$ttl, array &$setOpts ) + use ( $project, $language ) { + + $dbr = CNDatabase::getDb( DB_SLAVE ); + + // Account for slave lag to prevent a race condition when + // campaigns are updated, the cache is invalidated, and + // a client queries a yet-unsynced slave DBs + $setOpts += Database::getCacheSetOptions( $dbr ); + + return self::fetchChoices( $project, $language, $dbr ); }, [ 'checkKeys' => [ $checkKey ], @@ -59,11 +68,10 @@ } ); } - private static function fetchChoices( $project, $language ) { + private static function fetchChoices( $project, $language, $dbr ) { // For speed, we'll do our own queries instead of using methods in // Campaign and Banner. - $dbr = CNDatabase::getDb( DB_SLAVE ); $cache = ObjectCache::getMainWANInstance(); // Set up conditions -- To view, visit https://gerrit.wikimedia.org/r/308126 To unsubscribe, visit https://gerrit.wikimedia.org/r/settings Gerrit-MessageType: newchange Gerrit-Change-Id: Id4e46b653554d39ac5721c4327774ccfce63b734 Gerrit-PatchSet: 1 Gerrit-Project: mediawiki/extensions/CentralNotice Gerrit-Branch: master Gerrit-Owner: AndyRussG <andrew.green...@gmail.com> _______________________________________________ MediaWiki-commits mailing list MediaWiki-commits@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/mediawiki-commits
