YouTube API getPlaylistVideoFeedUrl issue - php

Question

I would like to add a video to a playlist using GData. So I have no problem creating the playlist, but I can't manage to add a video to it.
Here's what I do:
$playlist = $yt->newPlaylistListEntry();
$playlist->summary = $yt->newDescription()->setText("test");
$playlist->title = $yt->newTitle()->setText("test2");
$postLocation = 'http://gdata.youtube.com/feeds/api/users/default/playlists';
$yt->insertEntry($playlist, $postLocation);
$feedUrl = $playlist->getPlaylistVideoFeedUrl();
$videoEntryToAdd = $yt->getVideoEntry(..given id here..);
$newPlaylistListEntry = $yt->newPlaylistListEntry($videoEntryToAdd->getDOM());
$yt->insertEntry($newPlaylistListEntry, $feedUrl);
And I get the following error:
Notice: Trying to get property of non-object in C:...\library\Zend\Gdata\YouTube\PlaylistListEntry.php on line 296
Which is caused by this code:
$feedUrl = $playlist->getPlaylistVideoFeedUrl();
var_dump shows that the $feed_url is NULL. And it shows that $playlist is an object Zend_Gdata_YouTube_PlaylistListEntry, so I can't understand why it writes "property of non-object".

Answer 1

It seems like it is some kind of a bug in the API. So I've made a little workaround. It may seem ugly, but I had no other ideas.
function grab_dump($var)
{
ob_start();
var_dump($var);
return ob_get_clean();
}
function getPlayListLink($playlist) {
$test = grab_dump($playlist);
$test = strstr($test, "http://gdata.youtube.com/feeds/api/playlists/");
return strstr($test, "' countHint='0'", TRUE);
}
function addVideosToPlaylist($videos_arr, $playlistEntry, $yt) {
$feedUrl = getPlayListLink($playlistEntry);
foreach($videos_arr as $video)
{
$videoEntryToAdd = $yt->getVideoEntry($video);
$newPlaylistListEntry = $yt->newPlaylistListEntry($videoEntryToAdd->getDOM());
$yt->insertEntry($newPlaylistListEntry, $feedUrl);
}
}
And simply call it like that:
addVideosToPlaylist($vids_id, $playlist, $yt);