Turn MessageBlobStore into a singleton instead of static functions

For easier testability and other things. There are no uses
of this class in any extensions in gerrit.

Change-Id: I606de4259239e128ed7e0477fc98b84c647430c4

includes/MessageBlobStore.php

@@ -32,6 +32,21 @@
  * constituent messages or the resource itself is changed.
  */
 class MessageBlobStore {
+	/**
+	 * Get the singleton instance
+	 *
+	 * @since 1.24
+	 * @return MessageBlobStore
+	 */
+	public static function getInstance() {
+		static $instance = null;
+		if ( $instance === null ) {
+			$instance = new self;
+		}
+
+		return $instance;
+	}
+
 	/**
 	 * Get the message blobs for a set of modules
 	 *
@@ -40,19 +55,19 @@ class MessageBlobStore {
 	 * @param string $lang Language code
 	 * @return array An array mapping module names to message blobs
 	 */
-	public static function get( ResourceLoader $resourceLoader, $modules, $lang ) {
+	public function get( ResourceLoader $resourceLoader, $modules, $lang ) {
 		wfProfileIn( __METHOD__ );
 		if ( !count( $modules ) ) {
 			wfProfileOut( __METHOD__ );
 			return array();
 		}
 		// Try getting from the DB first
-		$blobs = self::getFromDB( $resourceLoader, array_keys( $modules ), $lang );
+		$blobs = $this->getFromDB( $resourceLoader, array_keys( $modules ), $lang );
 
 		// Generate blobs for any missing modules and store them in the DB
 		$missing = array_diff( array_keys( $modules ), array_keys( $blobs ) );
 		foreach ( $missing as $name ) {
-			$blob = self::insertMessageBlob( $name, $modules[$name], $lang );
+			$blob = $this->insertMessageBlob( $name, $modules[$name], $lang );
 			if ( $blob ) {
 				$blobs[$name] = $blob;
 			}
@@ -72,8 +87,8 @@ class MessageBlobStore {
 	 * @param string $lang Language code
 	 * @return mixed Message blob or false if the module has no messages
 	 */
-	public static function insertMessageBlob( $name, ResourceLoaderModule $module, $lang ) {
-		$blob = self::generateMessageBlob( $module, $lang );
+	public function insertMessageBlob( $name, ResourceLoaderModule $module, $lang ) {
+		$blob = $this->generateMessageBlob( $module, $lang );
 
 		if ( !$blob ) {
 			return false;
@@ -130,7 +145,7 @@ class MessageBlobStore {
 	 * @return string Regenerated message blob, or null if there was no blob for
 	 *   the given module/language pair.
 	 */
-	public static function updateModule( $name, ResourceLoaderModule $module, $lang ) {
+	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 ),
@@ -142,7 +157,7 @@ class MessageBlobStore {
 
 		// Save the old and new blobs for later
 		$oldBlob = $row->mr_blob;
-		$newBlob = self::generateMessageBlob( $module, $lang );
+		$newBlob = $this->generateMessageBlob( $module, $lang );
 
 		try {
 			$newRow = array(
@@ -197,7 +212,7 @@ class MessageBlobStore {
 	 *
 	 * @param string $key Message key
 	 */
-	public static function updateMessage( $key ) {
+	public function updateMessage( $key ) {
 		try {
 			$dbw = wfGetDB( DB_MASTER );
 
@@ -206,7 +221,7 @@ class MessageBlobStore {
 			// in one iteration.
 			$updates = null;
 			do {
-				$updates = self::getUpdatesForMessage( $key, $updates );
+				$updates = $this->getUpdatesForMessage( $key, $updates );
 
 				foreach ( $updates as $k => $update ) {
 					// Update the row on the condition that it
@@ -240,7 +255,7 @@ class MessageBlobStore {
 		}
 	}
 
-	public static function clear() {
+	public function clear() {
 		// TODO: Give this some more thought
 		try {
 			// Not using TRUNCATE, because that needs extra permissions,
@@ -260,7 +275,7 @@ class MessageBlobStore {
 	 * @param array $prevUpdates Updates queue to refresh or null to build a fresh update queue
 	 * @return array Updates queue
 	 */
-	private static function getUpdatesForMessage( $key, $prevUpdates = null ) {
+	private function getUpdatesForMessage( $key, $prevUpdates = null ) {
 		$dbw = wfGetDB( DB_MASTER );
 
 		if ( is_null( $prevUpdates ) ) {
@@ -297,7 +312,7 @@ class MessageBlobStore {
 				'resource' => $row->mr_resource,
 				'lang' => $row->mr_lang,
 				'timestamp' => $row->mr_timestamp,
-				'newBlob' => self::reencodeBlob( $row->mr_blob, $key, $row->mr_lang )
+				'newBlob' => $this->reencodeBlob( $row->mr_blob, $key, $row->mr_lang )
 			);
 		}
 
@@ -312,7 +327,7 @@ class MessageBlobStore {
 	 * @param string $lang Language code
 	 * @return string Message blob with $key replaced with its new value
 	 */
-	private static function reencodeBlob( $blob, $key, $lang ) {
+	private function reencodeBlob( $blob, $key, $lang ) {
 		$decoded = FormatJson::decode( $blob, true );
 		$decoded[$key] = wfMessage( $key )->inLanguage( $lang )->plain();
 
@@ -329,7 +344,7 @@ class MessageBlobStore {
 	 * @throws MWException
 	 * @return array Array mapping module names to blobs
 	 */
-	private static function getFromDB( ResourceLoader $resourceLoader, $modules, $lang ) {
+	private function getFromDB( ResourceLoader $resourceLoader, $modules, $lang ) {
 		global $wgCacheEpoch;
 
 		$retval = array();
@@ -354,7 +369,7 @@ class MessageBlobStore {
 			if ( $keys !== $values
 				|| wfTimestamp( TS_MW, $row->mr_timestamp ) <= $wgCacheEpoch
 			) {
-				$retval[$row->mr_resource] = self::updateModule( $row->mr_resource, $module, $lang );
+				$retval[$row->mr_resource] = $this->updateModule( $row->mr_resource, $module, $lang );
 			} else {
 				$retval[$row->mr_resource] = $row->mr_blob;
 			}
@@ -370,7 +385,7 @@ class MessageBlobStore {
 	 * @param string $lang Language code
 	 * @return string JSON object
 	 */
-	private static function generateMessageBlob( ResourceLoaderModule $module, $lang ) {
+	private function generateMessageBlob( ResourceLoaderModule $module, $lang ) {
 		$messages = array();
 
 		foreach ( $module->getMessages() as $key ) {

includes/cache/LocalisationCache.php

@@ -983,7 +983,7 @@ class LocalisationCache {
 		# HACK: If using a null (i.e. disabled) storage backend, we
 		# can't write to the MessageBlobStore either
 		if ( $purgeBlobs && !$this->store instanceof LCStoreNull ) {
-			MessageBlobStore::clear();
+			MessageBlobStore::getInstance()->clear();
 		}
 
 		wfProfileOut( __METHOD__ );

includes/cache/MessageCache.php

@@ -573,7 +573,7 @@ class MessageCache {
 
 		// Update the message in the message blob store
 		global $wgContLang;
-		MessageBlobStore::updateMessage( $wgContLang->lcfirst( $msg ) );
+		MessageBlobStore::getInstance()->updateMessage( $wgContLang->lcfirst( $msg ) );
 
 		wfRunHooks( 'MessageCacheReplace', array( $title, $text ) );
 

includes/installer/DatabaseUpdater.php

@@ -907,7 +907,7 @@ abstract class DatabaseUpdater {
 		if ( $wgLocalisationCacheConf['manualRecache'] ) {
 			$this->rebuildLocalisationCache();
 		}
-		MessageBlobStore::clear();
+		MessageBlobStore::getInstance()->clear();
 		$this->output( "done.\n" );
 	}
 

includes/resourceloader/ResourceLoader.php

@@ -855,7 +855,7 @@ class ResourceLoader {
 		// Pre-fetch blobs
 		if ( $context->shouldIncludeMessages() ) {
 			try {
-				$blobs = MessageBlobStore::get( $this, $modules, $context->getLanguage() );
+				$blobs = MessageBlobStore::getInstance()->get( $this, $modules, $context->getLanguage() );
 			} catch ( Exception $e ) {
 				MWExceptionHandler::logException( $e );
 				wfDebugLog(