/**
* Checks if the feed is valid.
*
* @return bool
* @param string $URL An URL where the feed is located or the XML of the feed.
* @param string[optional] $type The type of feed, possible values are: url, string.
*/
public static function isValid($URL, $type = 'url')
{
// redefine var
$URL = (string) $URL;
$type = (string) SpoonFilter::getValue($type, array('url', 'string'), 'url');
// validate
if ($type == 'url' && !SpoonFilter::isURL($URL)) {
throw new SpoonFeedException('This (' . $URL . ') isn\'t a valid url.');
}
// load xmlstring
if ($type == 'url') {
// check if allow_url_fopen is enabled
if (ini_get('allow_url_fopen') == 0) {
throw new SpoonFeedException('allow_url_fopen should be enabled, if you want to get a remote URL.');
}
// open the url
$handle = @fopen($URL, 'r');
// validate the handle
if ($handle === false) {
throw new SpoonFeedException('Something went wrong while retrieving the URL.');
}
// read the string
$xmlString = @stream_get_contents($handle);
// close the hanlde
@fclose($handle);
} else {
$xmlString = $URL;
}
// convert to simpleXML
$XML = @simplexml_load_string($xmlString);
// invalid XML?
if ($XML === false) {
return false;
}
// check if all needed elements are present
if (!isset($XML->title) || !isset($XML->id) || !isset($XML->entry)) {
return false;
}
// loop items
foreach ($XML->entry as $item) {
// validate items
if (!SpoonFeedAtomRSSItem::isValid($item)) {
return false;
}
}
// fallback
return true;
}