+
+ /**
+ * Fetch multiple blob items out of the database
+ *
+ * @param string $cluster A cluster name valid for use with LBFactory
+ * @param array $ids A map from the blob_id's to look for to the requested itemIDs in the blobs
+ * @return array A map from the blob_id's requested to their content. Unlocated ids are not represented
+ */
+ function batchFetchBlobs( $cluster, array $ids ) {
+ $dbr = $this->getSlave( $cluster );
+ $res = $dbr->select( $this->getTable( $dbr ), array( 'blob_id', 'blob_text' ), array( 'blob_id' => array_keys( $ids ) ), __METHOD__ );
+ $ret = array();
+ if ( $res !== false ) {
+ $this->mergeBatchResult( $ret, $ids, $res );
+ }
+ if ( $ids ) {
+ wfDebugLog( __CLASS__, __METHOD__ . " master fallback on '$cluster' for: " . implode( ',', array_keys( $ids ) ) . "\n" );
+ // Try the master
+ $dbw = $this->getMaster( $cluster );
+ $res = $dbw->select( $this->getTable( $dbr ), array( 'blob_id', 'blob_text' ), array( 'blob_id' => array_keys( $ids ) ), __METHOD__ );
+ if ( $res === false ) {
+ wfDebugLog( __CLASS__, __METHOD__ . " master failed on '$cluster'\n" );
+ } else {
+ $this->mergeBatchResult( $ret, $ids, $res );
+ }
+ }
+ if ( $ids ) {
+ wfDebugLog( __CLASS__, __METHOD__ . " master on '$cluster' failed locating items: " . implode( ',', array_keys( $ids ) ) . "\n" );
+ }
+ return $ret;
+ }
+
+ /**
+ * Helper function for self::batchFetchBlobs for merging master/slave results
+ * @param array &$ret Current self::batchFetchBlobs return value
+ * @param array &$ids Map from blob_id to requested itemIDs
+ * @param mixed $res DB result from DatabaseBase::select
+ */
+ private function mergeBatchResult( array &$ret, array &$ids, $res ) {
+ foreach ( $res as $row ) {
+ $id = $row->blob_id;
+ $itemIDs = $ids[$id];
+ unset( $ids[$id] ); // to track if everything is found
+ if ( count( $itemIDs ) === 1 && reset( $itemIDs ) === false ) {
+ // single result stored per blob
+ $ret[$id] = $row->blob_text;
+ } else {
+ // multi result stored per blob
+ $ret[$id] = unserialize( $row->blob_text );
+ }
+ }
+ }
+
+ protected function parseURL( $url ) {
+ $path = explode( '/', $url );
+ return array(
+ $path[2], // cluster
+ $path[3], // id
+ isset( $path[4] ) ? $path[4] : false // itemID
+ );
+ }