Checks a news feed for new items.
$feed: An object describing the feed to be refreshed.
function aggregator_refresh($feed) {
// Store feed URL to track changes.
$feed_url = $feed->url;
list($fetcher, $parser, $processors) = _aggregator_get_variables();
// Fetch the feed.
$fetcher_manager = new FetcherManager();
try {
$success = $fetcher_manager
->createInstance($fetcher)
->fetch($feed);
} catch (PluginException $e) {
$success = FALSE;
}
// We store the hash of feed data in the database. When refreshing a
// feed we compare stored hash and new hash calculated from downloaded
// data. If both are equal we say that feed is not updated.
$hash = hash('sha256', $feed->source_string);
if ($success && $feed->hash != $hash) {
// Parse the feed.
if (module_invoke($parser, 'aggregator_parse', $feed)) {
// Update feed with parsed data.
db_merge('aggregator_feed')
->key(array(
'fid' => $feed->fid,
))
->fields(array(
'url' => $feed->url,
'link' => empty($feed->link) ? $feed->url : $feed->link,
'description' => empty($feed->description) ? '' : $feed->description,
'image' => empty($feed->image) ? '' : $feed->image,
'hash' => $hash,
'etag' => empty($feed->etag) ? '' : $feed->etag,
'modified' => empty($feed->modified) ? 0 : $feed->modified,
))
->execute();
// Log if feed URL has changed.
if ($feed->url != $feed_url) {
watchdog('aggregator', 'Updated URL for feed %title to %url.', array(
'%title' => $feed->title,
'%url' => $feed->url,
));
}
watchdog('aggregator', 'There is new syndicated content from %site.', array(
'%site' => $feed->title,
));
drupal_set_message(t('There is new syndicated content from %site.', array(
'%site' => $feed->title,
)));
// If there are items on the feed, let all enabled processors do their work on it.
if (@count($feed->items)) {
foreach ($processors as $processor) {
module_invoke($processor, 'aggregator_process', $feed);
}
}
}
}
else {
drupal_set_message(t('There is no new syndicated content from %site.', array(
'%site' => $feed->title,
)));
}
// Regardless of successful or not, indicate that this feed has been checked.
db_update('aggregator_feed')
->fields(array(
'checked' => REQUEST_TIME,
'queued' => 0,
))
->condition('fid', $feed->fid)
->execute();
// Expire old feed items.
if (function_exists('aggregator_expire')) {
aggregator_expire($feed);
}
}