过滤嵌套序列化程序 model 字段（排除特定字段）

Question

我是Django的新手，我试图在嵌套序列化程序中exclude model 字段。

模态.py

class Blog(models.Model):
    title = models.CharField(max_length=30)
    description = models.CharField(max_length=30)

class Comment(models.Model):
    blog = models.ForeignKey(Blog, on_delete=models.CASCADE, related_name="comment")
    comment_bdy = models.CharField(max_length=30)
    completed = models.BooleanField(default=False)

序列化程序.py

class BlogCommentSerializer(serializers.ModelSerializer):

    class Meta:
        model = Comment
        fields = ("id", "comment_body")

class BlogSerializer(serializers.ModelSerializer):
    comment = BlogCommentSerializer(many=True)
    
    class Meta:
        model = ("id", "title", "description", "comment",)

我试图排除已completed=True的comment 。

我试过很多次，比如：-

class BlogCommentSerializer(serializers.ModelSerializer):

    def to_representation(self, data):
        data = data.filter(completed=False)
        return super(BlogCommentSerializer, self).to_representation(data)

但它显示：

AttributeError: 'CommentReply' object 没有属性 'filter'

然后我尝试使用：

class BlogSerializer(serializers.ModelSerializer):

    def get_comment(self, instance):
        comment_instance = instance.comment_set.exclude(completed=True)
        return BlogSerializer(comment_instance , many=True).data

它也没有用。

我想做什么

我试图排除completed=True的评论。

Answer 1

您可以使用SerializerMethodField尝试这样：

class BlogSerializer(serializers.ModelSerializer):
    comment = serializers.SerializerMethodField()

    def get_comment(self, instance):
        comment_instances = instance.comment.exclude(completed=True)
        return BlogCommentSerializer(comment_instances , many=True).data

Answer 2

尝试一下：

class BlogSerializer(serializers.ModelSerializer):
    comment = serializers.SerializerMethodField()

    def get_comment(self, obj):
        queryset = Comment.objects.
            filter(blog=obj).exclude(blog__completed=True)
        return [BlogCommentSerializer(q).data for q in queryset]