/**
* Generates feed's content
*
* @param ChannelFeed $feed ChannelFeed subclass object (generally the one returned
* by getFeedObject())
* @param ResultWrapper $rows ResultWrapper object with rows in recentchanges table
* @param int $lastmod Timestamp of the last item in the recentchanges table (only
* used for the cache key)
* @param FormOptions $opts As in SpecialRecentChanges::getDefaultOptions()
* @return null|bool True or null
*/
public function execute($feed, $rows, $lastmod, $opts)
{
global $wgLang, $wgRenderHashAppend;
if (!FeedUtils::checkFeedOutput($this->format)) {
return null;
}
$optionsHash = md5(serialize($opts->getAllValues())) . $wgRenderHashAppend;
$timekey = wfMemcKey($this->type, $this->format, $wgLang->getCode(), $optionsHash, 'timestamp');
$key = wfMemcKey($this->type, $this->format, $wgLang->getCode(), $optionsHash);
FeedUtils::checkPurge($timekey, $key);
/**
* Bumping around loading up diffs can be pretty slow, so where
* possible we want to cache the feed output so the next visitor
* gets it quick too.
*/
$cachedFeed = $this->loadFromCache($lastmod, $timekey, $key);
if (is_string($cachedFeed)) {
wfDebug("RC: Outputting cached feed\n");
$feed->httpHeaders();
echo $cachedFeed;
} else {
wfDebug("RC: rendering new feed and caching it\n");
ob_start();
self::generateFeed($rows, $feed);
$cachedFeed = ob_get_contents();
ob_end_flush();
$this->saveToCache($cachedFeed, $timekey, $key);
}
return true;
}
