如何在 DRF 的序列化程序中获取嵌套对象的详细信息答案

【问题标题】：How to get details of a nested object in a serializer in DRF如何在 DRF 的序列化程序中获取嵌套对象的详细信息
【发布时间】：2020-04-06 16:09:10
【问题描述】：

所以我正在尝试创建一个序列化程序，它会在我的项目中返回一堆“发布”模型的详细信息，但我也想获取嵌套对象的详细信息，我将在下面显示其输出:
后模型：

class Post(models.Model):

    # Base post attributes
    user = models.ForeignKey(UserOfApp, related_name="posts", on_delete=models.CASCADE)
    ...
    # Repost post attributes
    original_repost = models.ForeignKey(
        to="self",
        related_name="reposted_post",
        null=True,
        blank=True,
        on_delete=models.CASCADE,
    )

    # Quote post attributes
    is_quote_post = models.BooleanField(default=False)
    quoted_post = models.ForeignKey(
        to="self", null=True, blank=True, on_delete=models.CASCADE
    )
    ...

我的序列化器，使用“深度”：

class HomeSerializer(serializers.ModelSerializer):

    id_str = serializers.ReadOnlyField()
    ...
    quoted_post_id_str = serializers.ReadOnlyField()

    class Meta:
        model = Post
        depth = 2
        fields = "__all__"

这会产生类似的输出，问题是它也会从我的用户模型返回所有敏感数据，例如“密码”等：

{
        "id": 16,
        ...
        "is_quote_post": false,
        "user": {
            "id": 1,
            "password": "pbkdf2_sha256$180000$ni6drJvLjUU2$xoMt5tpJmz8TlmORfB/eTkYlGGpUGfriGz8rO7kVB8E=",
            "last_login": "2020-03-21T06:20:48Z",
            "is_superuser": true,
            "username": "manas",
            "first_name": "Manas",
            "last_name": "Acharekar",
            "email": "manas.acharekar98@gmail.com",
            "is_staff": true,
            "is_active": true,
            "date_joined": "2020-03-01T18:42:11Z",
            "dob": "1998-11-11",
            "gender": "M",
            "bio": "i own this place",
            "location": "",
            "website": "",
            "verified": true,
            "followers": [],
            "friends": [],
            "groups": [],
            "user_permissions": []
        },
        "original_repost": {
            "id": 1,
            ...
            "user": {
                "id": 1,
                "password": "pbkdf2_sha256$180000$ni6drJvLjUU2$xoMt5tpJmz8TlmORfB/eTkYlGGpUGfriGz8rO7kVB8E=",
                "last_login": "2020-03-21T06:20:48Z",
                "is_superuser": true,
                "username": "manas",
                "first_name": "Manas",
                "last_name": "Acharekar",
                "email": "manas.acharekar98@gmail.com",
                "is_staff": true,
                "is_active": true,
                "date_joined": "2020-03-01T18:42:11Z",
                "dob": "1998-11-11",
                "gender": "M",
                "bio": "i own this place",
                "location": "",
                "website": "",
                "verified": true,
                "followers": [],
                "friends": [],
                "groups": [],
                "user_permissions": []
            },
            "original_repost": null,
            "quoted_post": null
        },
        "quoted_post": null
    }

我的序列化器，不使用深度：

class HomeSerializer(serializers.ModelSerializer):
    user = UserSerializer()
    id_str = serializers.ReadOnlyField()
    ...
    quoted_post_id_str = serializers.ReadOnlyField()
    quoted_post = PostSerializer()
    original_repost = PostSerializer()

    class Meta:
        model = Post
        fields = "__all__"

这会正确输出帖子，但我无法获得完整的嵌套对象。在下面提到的返回 JSON 中，我想访问 quoted_post.user 或 original_repost.user，但只返回一个外键：

{
        "id": 16,
        "user": {
            "id": 1,
            "followers_count": 0,
            "friends_count": 0,
            "username": "manas",
            "first_name": "Manas",
            "last_name": "Acharekar",
            "email": "manas.acharekar98@gmail.com",
            "date_joined": "2020-03-01T18:42:11Z",
            "dob": "1998-11-11",
            "gender": "M",
            "bio": "i own this place",
            "location": "",
            "website": "",
            "verified": true,
            "followers": [],
            "friends": []
        },
        "id_str": "16",
        ...
        "quoted_post": null,
        "original_repost": {
            "id": 1,
            ...
            "is_quote_post": false,
            "user": 1,
            "original_repost": null,
            "quoted_post": null
        },
        ...
        "is_quote_post": false
    }

我该如何解决这个问题？

【问题讨论】：

使用嵌套序列化程序
@ArakkalAbu 我该怎么做？可以发一些相关的链接吗？

标签： python json django rest django-rest-framework

【解决方案1】：

在你的情况下，最好是修改 PostSerializer()。

class PostSerializer(serializers.ModelSerializer):
    user = UserSerializer()

    class Meta:
        model = Post
        fields = "__all__"

class HomeSerializer(serializers.ModelSerializer):
    user = UserSerializer()
    id_str = serializers.ReadOnlyField()
    ...
    quoted_post_id_str = serializers.ReadOnlyField()
    quoted_post = PostSerializer()
    original_repost = PostSerializer()

    class Meta:
        model = Post
        fields = "__all__"

另外，我建议不要使用 __all__，因为它可能会泄露一些不必要的数据。

尝试明确定义要显示的字段

class UserSerializer(serializers.ModelSerializer):

    class Meta:
        model = User
        fields = ["first_name","last_name" ]

【讨论】：