我試圖創建曲目的專輯,但我被困在一個錯誤錯誤不能讀取屬性「跟蹤」空的(node.js的)
這是我的路線代碼
// Adding track to album
router.get('/:album_id/track/new', function(req, res){
Album.findById(req.params.album_id, function(err, falbum){
if(err){
console.log(err);
} else {
res.render('tracks/add', {albums: falbum});
}
});
});
// Post routes
router.post('/:album_id/track',upload.single('songs'), function(req, res){
Album.findById(req.params.album_id, function(err, album){
if(err){
console.log(err);
} else {
if(req.file){
console.log('Uploading Song ....');
var songs = req.file.filename;
} else {
console.log('No Song Uploaded...');
}
var songname = req.body.songname;
var songs = songs;
var newSong = {songname: songname, songs:songs};
Track.create(newSong, function(err, track){
if(err){
console.log(err);
} else {
track.albumId.id = req.params.album_id;
track.save();
album.tracks.push(track);
album.save();
console.log('New Track is created');
res.redirect('/albums/' + album._id);
}
});
}
});
});
router.get('/:album_id',function(req, res){
Album.findById(req.params.album_id).populate('tracks').exec(function(err, album){
if(err){
console.log(err);
} else {
res.render('albums/show', {albums: album})
}
});
});
module.exports = router;
我得到以下錯誤
v4\node_modules\mongoose\node_modules\mongodb\lib\utils.js:98
process.nextTick(function() { throw err; });
^
TypeError: Cannot read property 'tracks' of null
at C:\Users\tjesu\Desktop\pidal\pidal-v4\routes\albums.js:53:11
at Function.<anonymous> (C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\mongoose\lib\model.js:3324:16)
at C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\mongoose\lib\model.js:1870:14
at C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\async\lib\async.js:726:13
at C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\async\lib\async.js:52:16
at done (C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\async\lib\async.js:246:17)
at C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\async\lib\async.js:44:16
at C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\async\lib\async.js:723:17
at C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\async\lib\async.js:167:37
at model.callbackWrapper (C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\mongoose\lib\model.js:1843:11)
at next_ (C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\hooks-fixed\hooks.js:89:34)
at fnWrapper (C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\hooks-fixed\hooks.js:186:8)
at C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\mongoose\lib\model.js:3324:16
at C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\mongoose\lib\model.js:228:5
at C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\mongoose\lib\model.js:135:7
at C:\Users\tjesu\Desktop\pidal\pidal-v4\node_modules\mongoose\node_modules\mongodb\lib\collection.js:504:5
我該怎麼辦?這個錯誤呢? 我試圖改變曲目來跟蹤,但我仍然有錯誤 謝謝!
也許我錯了,但我認爲你的查詢Album.findById(req.params.album_id)不返回結果這就是爲什麼填充拋出錯誤。試着檢查查詢是否實際查找數據。希望這可以幫助。 –
錯誤意味着一件事,'Album.findById()'查詢沒有找到與'album_id'匹配的任何文檔,因此回調中的結果變量'album'是未定義的,因此在'album.tracks上拋出一個錯誤。推(軌道);'。您需要先檢查結果是否爲文檔。 – chridam
你能展示你的模式嗎?你也可以知道它指的是哪一行:'C:\ Users \ tjesu \ Desktop \ pidal \ pidal-v4 \ routes \ albums.js:53:11' –