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diff --git a/includes/cache/MessageBlobStore.php b/includes/cache/MessageBlobStore.php
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+<?php
+/**
+ * Resource message blobs storage used by the resource loader.
+ *
+ * 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
+ * @author Roan Kattouw
+ * @author Trevor Parscal
+ */
+
+/**
+ * This class provides access to the resource message blobs storage used by
+ * the ResourceLoader.
+ *
+ * A message blob is a JSON object containing the interface messages for a
+ * certain resource in a certain language. These message blobs are cached
+ * in the msg_resource table and automatically invalidated when one of their
+ * constituent messages or the resource itself is changed.
+ */
+class MessageBlobStore {
+ /**
+ * In-process cache for message blobs.
+ *
+ * Keyed by language code, then module name.
+ *
+ * @var array
+ */
+ protected $blobCache = array();
+
+ /**
+ * Get the singleton instance
+ *
+ * @since 1.24
+ * @deprecated since 1.25
+ * @return MessageBlobStore
+ */
+ public static function getInstance() {
+ wfDeprecated( __METHOD__, '1.25' );
+ return new self;
+ }
+
+ /**
+ * Get the message blobs for a set of modules
+ *
+ * @param ResourceLoader $resourceLoader
+ * @param array $modules Array of module objects keyed by module name
+ * @param string $lang Language code
+ * @return array An array mapping module names to message blobs
+ */
+ public function get( ResourceLoader $resourceLoader, $modules, $lang ) {
+ if ( !count( $modules ) ) {
+ return array();
+ }
+
+ $blobs = array();
+
+ // Try in-process cache
+ $missingFromCache = array();
+ foreach ( $modules as $name => $module ) {
+ if ( isset( $this->blobCache[$lang][$name] ) ) {
+ $blobs[$name] = $this->blobCache[$lang][$name];
+ } else {
+ $missingFromCache[] = $name;
+ }
+ }
+
+ // Try DB cache
+ if ( $missingFromCache ) {
+ $blobs += $this->getFromDB( $resourceLoader, $missingFromCache, $lang );
+ }
+
+ // Generate new blobs for any remaining modules and store in DB
+ $missingFromDb = array_diff( array_keys( $modules ), array_keys( $blobs ) );
+ foreach ( $missingFromDb as $name ) {
+ $blob = $this->insertMessageBlob( $name, $modules[$name], $lang );
+ if ( $blob ) {
+ $blobs[$name] = $blob;
+ }
+ }
+
+ // Update in-process cache
+ if ( isset( $this->blobCache[$lang] ) ) {
+ $this->blobCache[$lang] += $blobs;
+ } else {
+ $this->blobCache[$lang] = $blobs;
+ }
+
+ return $blobs;
+ }
+
+ /**
+ * Generate and insert a new message blob. If the blob was already
+ * present, it is not regenerated; instead, the preexisting blob
+ * is fetched and returned.
+ *
+ * @param string $name Module name
+ * @param ResourceLoaderModule $module
+ * @param string $lang Language code
+ * @return mixed Message blob or false if the module has no messages
+ */
+ public function insertMessageBlob( $name, ResourceLoaderModule $module, $lang ) {
+ $blob = $this->generateMessageBlob( $module, $lang );
+
+ if ( !$blob ) {
+ return false;
+ }
+
+ try {
+ $dbw = wfGetDB( DB_MASTER );
+ $success = $dbw->insert( 'msg_resource', array(
+ 'mr_lang' => $lang,
+ 'mr_resource' => $name,
+ 'mr_blob' => $blob,
+ 'mr_timestamp' => $dbw->timestamp()
+ ),
+ __METHOD__,
+ array( 'IGNORE' )
+ );
+
+ if ( $success ) {
+ if ( $dbw->affectedRows() == 0 ) {
+ // Blob was already present, fetch it
+ $blob = $dbw->selectField( 'msg_resource', 'mr_blob', array(
+ 'mr_resource' => $name,
+ 'mr_lang' => $lang,
+ ),
+ __METHOD__
+ );
+ } else {
+ // Update msg_resource_links
+ $rows = array();
+
+ foreach ( $module->getMessages() as $key ) {
+ $rows[] = array(
+ 'mrl_resource' => $name,
+ 'mrl_message' => $key
+ );
+ }
+ $dbw->insert( 'msg_resource_links', $rows,
+ __METHOD__, array( 'IGNORE' )
+ );
+ }
+ }
+ } catch ( DBError $e ) {
+ wfDebug( __METHOD__ . " failed to update DB: $e\n" );
+ }
+ return $blob;
+ }
+
+ /**
+ * Update the message blob for a given module in a given language
+ *
+ * @param string $name Module name
+ * @param ResourceLoaderModule $module
+ * @param string $lang Language code
+ * @return string Regenerated message blob, or null if there was no blob for
+ * the given module/language pair.
+ */
+ public function updateModule( $name, ResourceLoaderModule $module, $lang ) {
+ $dbw = wfGetDB( DB_MASTER );
+ $row = $dbw->selectRow( 'msg_resource', 'mr_blob',
+ array( 'mr_resource' => $name, 'mr_lang' => $lang ),
+ __METHOD__
+ );
+ if ( !$row ) {
+ return null;
+ }
+
+ // Save the old and new blobs for later
+ $oldBlob = $row->mr_blob;
+ $newBlob = $this->generateMessageBlob( $module, $lang );
+
+ try {
+ $newRow = array(
+ 'mr_resource' => $name,
+ 'mr_lang' => $lang,
+ 'mr_blob' => $newBlob,
+ 'mr_timestamp' => $dbw->timestamp()
+ );
+
+ $dbw->replace( 'msg_resource',
+ array( array( 'mr_resource', 'mr_lang' ) ),
+ $newRow, __METHOD__
+ );
+
+ // Figure out which messages were added and removed
+ $oldMessages = array_keys( FormatJson::decode( $oldBlob, true ) );
+ $newMessages = array_keys( FormatJson::decode( $newBlob, true ) );
+ $added = array_diff( $newMessages, $oldMessages );
+ $removed = array_diff( $oldMessages, $newMessages );
+
+ // Delete removed messages, insert added ones
+ if ( $removed ) {
+ $dbw->delete( 'msg_resource_links', array(
+ 'mrl_resource' => $name,
+ 'mrl_message' => $removed
+ ), __METHOD__
+ );
+ }
+
+ $newLinksRows = array();
+
+ foreach ( $added as $message ) {
+ $newLinksRows[] = array(
+ 'mrl_resource' => $name,
+ 'mrl_message' => $message
+ );
+ }
+
+ if ( $newLinksRows ) {
+ $dbw->insert( 'msg_resource_links', $newLinksRows, __METHOD__,
+ array( 'IGNORE' ) // just in case
+ );
+ }
+ } catch ( Exception $e ) {
+ wfDebug( __METHOD__ . " failed to update DB: $e\n" );
+ }
+ return $newBlob;
+ }
+
+ /**
+ * Update a single message in all message blobs it occurs in.
+ *
+ * @param string $key Message key
+ */
+ public function updateMessage( $key ) {
+ try {
+ $dbw = wfGetDB( DB_MASTER );
+
+ // Keep running until the updates queue is empty.
+ // Due to update conflicts, the queue might not be emptied
+ // in one iteration.
+ $updates = null;
+ do {
+ $updates = $this->getUpdatesForMessage( $key, $updates );
+
+ foreach ( $updates as $k => $update ) {
+ // Update the row on the condition that it
+ // didn't change since we fetched it by putting
+ // the timestamp in the WHERE clause.
+ $success = $dbw->update( 'msg_resource',
+ array(
+ 'mr_blob' => $update['newBlob'],
+ 'mr_timestamp' => $dbw->timestamp() ),
+ array(
+ 'mr_resource' => $update['resource'],
+ 'mr_lang' => $update['lang'],
+ 'mr_timestamp' => $update['timestamp'] ),
+ __METHOD__
+ );
+
+ // Only requeue conflicted updates.
+ // If update() returned false, don't retry, for
+ // fear of getting into an infinite loop
+ if ( !( $success && $dbw->affectedRows() == 0 ) ) {
+ // Not conflicted
+ unset( $updates[$k] );
+ }
+ }
+ } while ( count( $updates ) );
+
+ // No need to update msg_resource_links because we didn't add
+ // or remove any messages, we just changed their contents.
+ } catch ( Exception $e ) {
+ wfDebug( __METHOD__ . " failed to update DB: $e\n" );
+ }
+ }
+
+ public function clear() {
+ // TODO: Give this some more thought
+ try {
+ // Not using TRUNCATE, because that needs extra permissions,
+ // which maybe not granted to the database user.
+ $dbw = wfGetDB( DB_MASTER );
+ $dbw->delete( 'msg_resource', '*', __METHOD__ );
+ $dbw->delete( 'msg_resource_links', '*', __METHOD__ );
+ } catch ( Exception $e ) {
+ wfDebug( __METHOD__ . " failed to update DB: $e\n" );
+ }
+ }
+
+ /**
+ * Create an update queue for updateMessage()
+ *
+ * @param string $key Message key
+ * @param array $prevUpdates Updates queue to refresh or null to build a fresh update queue
+ * @return array Updates queue
+ */
+ private function getUpdatesForMessage( $key, $prevUpdates = null ) {
+ $dbw = wfGetDB( DB_MASTER );
+
+ if ( is_null( $prevUpdates ) ) {
+ // Fetch all blobs referencing $key
+ $res = $dbw->select(
+ array( 'msg_resource', 'msg_resource_links' ),
+ array( 'mr_resource', 'mr_lang', 'mr_blob', 'mr_timestamp' ),
+ array( 'mrl_message' => $key, 'mr_resource=mrl_resource' ),
+ __METHOD__
+ );
+ } else {
+ // Refetch the blobs referenced by $prevUpdates
+
+ // Reorganize the (resource, lang) pairs in the format
+ // expected by makeWhereFrom2d()
+ $twoD = array();
+
+ foreach ( $prevUpdates as $update ) {
+ $twoD[$update['resource']][$update['lang']] = true;
+ }
+
+ $res = $dbw->select( 'msg_resource',
+ array( 'mr_resource', 'mr_lang', 'mr_blob', 'mr_timestamp' ),
+ $dbw->makeWhereFrom2d( $twoD, 'mr_resource', 'mr_lang' ),
+ __METHOD__
+ );
+ }
+
+ // Build the new updates queue
+ $updates = array();
+
+ foreach ( $res as $row ) {
+ $updates[] = array(
+ 'resource' => $row->mr_resource,
+ 'lang' => $row->mr_lang,
+ 'timestamp' => $row->mr_timestamp,
+ 'newBlob' => $this->reencodeBlob( $row->mr_blob, $key, $row->mr_lang )
+ );
+ }
+
+ return $updates;
+ }
+
+ /**
+ * Reencode a message blob with the updated value for a message
+ *
+ * @param string $blob Message blob (JSON object)
+ * @param string $key Message key
+ * @param string $lang Language code
+ * @return string Message blob with $key replaced with its new value
+ */
+ private function reencodeBlob( $blob, $key, $lang ) {
+ $decoded = FormatJson::decode( $blob, true );
+ $decoded[$key] = wfMessage( $key )->inLanguage( $lang )->plain();
+
+ return FormatJson::encode( (object)$decoded );
+ }
+
+ /**
+ * Get the message blobs for a set of modules from the database.
+ * Modules whose blobs are not in the database are silently dropped.
+ *
+ * @param ResourceLoader $resourceLoader
+ * @param array $modules Array of module names
+ * @param string $lang Language code
+ * @throws MWException
+ * @return array Array mapping module names to blobs
+ */
+ private function getFromDB( ResourceLoader $resourceLoader, $modules, $lang ) {
+ if ( !count( $modules ) ) {
+ return array();
+ }
+
+ $config = $resourceLoader->getConfig();
+ $retval = array();
+ $dbr = wfGetDB( DB_SLAVE );
+ $res = $dbr->select( 'msg_resource',
+ array( 'mr_blob', 'mr_resource', 'mr_timestamp' ),
+ array( 'mr_resource' => $modules, 'mr_lang' => $lang ),
+ __METHOD__
+ );
+
+ foreach ( $res as $row ) {
+ $module = $resourceLoader->getModule( $row->mr_resource );
+ if ( !$module ) {
+ // This shouldn't be possible
+ throw new MWException( __METHOD__ . ' passed an invalid module name' );
+ }
+
+ // Update the module's blobs if the set of messages changed or if the blob is
+ // older than the CacheEpoch setting
+ $keys = array_keys( FormatJson::decode( $row->mr_blob, true ) );
+ $values = array_values( array_unique( $module->getMessages() ) );
+ if ( $keys !== $values
+ || wfTimestamp( TS_MW, $row->mr_timestamp ) <= $config->get( 'CacheEpoch' )
+ ) {
+ $retval[$row->mr_resource] = $this->updateModule( $row->mr_resource, $module, $lang );
+ } else {
+ $retval[$row->mr_resource] = $row->mr_blob;
+ }
+ }
+
+ return $retval;
+ }
+
+ /**
+ * Generate the message blob for a given module in a given language.
+ *
+ * @param ResourceLoaderModule $module
+ * @param string $lang Language code
+ * @return string JSON object
+ */
+ private function generateMessageBlob( ResourceLoaderModule $module, $lang ) {
+ $messages = array();
+
+ foreach ( $module->getMessages() as $key ) {
+ $messages[$key] = wfMessage( $key )->inLanguage( $lang )->plain();
+ }
+
+ return FormatJson::encode( (object)$messages );
+ }
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-21 21:07:12 +0000