+ /**
+ * Get the temporary prepared edit stash key for a user
+ *
+ * This key can be used for caching prepared edits provided:
+ * - a) The $user was used for PST options
+ * - b) The parser output was made from the PST using cannonical matching options
+ *
+ * @param Title $title
+ * @param Content $content
+ * @param User $user User to get parser options from
+ * @return string
+ */
+ protected static function getStashKey( Title $title, Content $content, User $user ) {
+ $hash = sha1( implode( ':', array(
+ $content->getModel(),
+ $content->getDefaultFormat(),
+ sha1( $content->serialize( $content->getDefaultFormat() ) ),
+ $user->getId() ?: md5( $user->getName() ), // account for user parser options
+ $user->getId() ? $user->getTouched() : '-' // handle preference change races
+ ) ) );
+
+ return wfMemcKey( 'prepared-edit', md5( $title->getPrefixedDBkey() ), $hash );
+ }
+
+ /**
+ * Build a value to store in memcached based on the PST content and parser output
+ *
+ * This makes a simple version of WikiPage::prepareContentForEdit() as stash info
+ *
+ * @param Content $pstContent
+ * @param ParserOutput $parserOutput
+ * @param string $timestamp TS_MW
+ * @return array (stash info array, TTL in seconds) or (null, 0)
+ */
+ protected static function buildStashValue(
+ Content $pstContent, ParserOutput $parserOutput, $timestamp
+ ) {
+ // If an item is renewed, mind the cache TTL determined by config and parser functions
+ $since = time() - wfTimestamp( TS_UNIX, $parserOutput->getTimestamp() );
+ $ttl = min( $parserOutput->getCacheExpiry() - $since, 5 * 60 );
+
+ if ( $ttl > 0 && !$parserOutput->getFlag( 'vary-revision' ) ) {
+ // Only store what is actually needed
+ $stashInfo = (object)array(
+ 'pstContent' => $pstContent,
+ 'output' => $parserOutput,
+ 'timestamp' => $timestamp
+ );
+ return array( $stashInfo, $ttl );
+ }
+
+ return array( null, 0 );
+ }
+