+abstract class Preprocessor {
+
+ const CACHE_VERSION = 1;
+
+ /**
+ * @var array Brace matching rules.
+ */
+ protected $rules = [
+ '{' => [
+ 'end' => '}',
+ 'names' => [
+ 2 => 'template',
+ 3 => 'tplarg',
+ ],
+ 'min' => 2,
+ 'max' => 3,
+ ],
+ '[' => [
+ 'end' => ']',
+ 'names' => [ 2 => null ],
+ 'min' => 2,
+ 'max' => 2,
+ ],
+ '-{' => [
+ 'end' => '}-',
+ 'names' => [ 2 => null ],
+ 'min' => 2,
+ 'max' => 2,
+ ],
+ ];
+
+ /**
+ * Store a document tree in the cache.
+ *
+ * @param string $text
+ * @param int $flags
+ * @param string $tree
+ */
+ protected function cacheSetTree( $text, $flags, $tree ) {
+ $config = RequestContext::getMain()->getConfig();
+
+ $length = strlen( $text );
+ $threshold = $config->get( 'PreprocessorCacheThreshold' );
+ if ( $threshold === false || $length < $threshold || $length > 1e6 ) {
+ return;
+ }
+
+ $cache = ObjectCache::getLocalClusterInstance();
+ $key = $cache->makeKey(
+ defined( 'static::CACHE_PREFIX' ) ? static::CACHE_PREFIX : static::class,
+ md5( $text ), $flags );
+ $value = sprintf( "%08d", static::CACHE_VERSION ) . $tree;
+
+ $cache->set( $key, $value, 86400 );
+
+ LoggerFactory::getInstance( 'Preprocessor' )
+ ->info( "Cached preprocessor output (key: $key)" );
+ }
+
+ /**
+ * Attempt to load a precomputed document tree for some given wikitext
+ * from the cache.
+ *
+ * @param string $text
+ * @param int $flags
+ * @return PPNode_Hash_Tree|bool
+ */
+ protected function cacheGetTree( $text, $flags ) {
+ $config = RequestContext::getMain()->getConfig();
+
+ $length = strlen( $text );
+ $threshold = $config->get( 'PreprocessorCacheThreshold' );
+ if ( $threshold === false || $length < $threshold || $length > 1e6 ) {
+ return false;
+ }
+
+ $cache = ObjectCache::getLocalClusterInstance();
+
+ $key = $cache->makeKey(
+ defined( 'static::CACHE_PREFIX' ) ? static::CACHE_PREFIX : static::class,
+ md5( $text ), $flags );