有没有办法订购嵌套的序列化器_set,例如按pk或时间戳排序.
因此,基本上将json数据中显示的song_set从最相邻的最新对象创建,在本例中为order_by(‘ – timestamp’)或order_by(‘ – pk’).
Json数据
{
"pk": 151,"album_name": "Name","song_set": [
{
pk: 3,timestamp: '5 seconds'
},{
pk: 2,timestamp: '10 seconds'
},{
pk: 1,timestamp: '15 seconds'
}
]
}
模型
class Album(models.Model):
album_name = models.CharField(max_length=100,blank=True)
class Song(models.Model):
album = models.ForeignKey('album.Album',default=1)
timestamp = models.DateTimeField(auto_now_add=True,auto_now=False)
Searilizer
class SongListSerializer(HyperlinkedModelSerializer):
class Meta:
model = Song
fields = [
'pk','timestamp'
]
class AlbumSerializer(HyperlinkedModelSerializer):
song_set = SongListSerializer(many=True,read_only=True)
class Meta:
model = Album
fields = [
'pk','timestamp','song_set'
]
解决方法
您可以使用SerializerMethodField并为此编写自定义方法.
class AlbumSerializer(HyperlinkedModelSerializer):
song_set = serializer.SerializerMethodField()
class Meta:
model = Album
fields = [
'pk','song_set'
]
def get_song_set(self,instance):
songs = instance.song_set.all().order_by('-timestamp')
return SongListSerializer(songs,many=True).data