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如何使用Django REST序列化程序对保留密钥进行验证?

serialization django-rest-framework django python

joe · 技术社区 · 6 年前

这可能是一个关于眨眼的简单问题。但我无法完成。我现在正在创建 webhook 端点。并卡在 serializer 班我的班级不能使用 from 作为类属性

Python 3.6.4
Django==1.11.9
djangorest==3.7.7

@pytest.fixture
def like_object():
    """LIKE object response from Facebook"""
    return {
        "object": "page",
        "entry": [{
            "changes": [{
                "field": "feed",
                "value": {
                    "item": "reaction",
                    "verb": "add",
                    "reaction_type": "like",
                    "created_time": 1516183830,
                    "post_id": "1331351323541869_1844740022202994",
                    "from": {
                        "name": "Elcoie Sieve",
                        "id": "1639217166122728"
                    },
                    "parent_id": "1331351323541869_1844740022202994"
                }
            }],
            "time": 1516183830, "id": "1331351323541869"
        }]
    }

serializers.py

class FacebookReactionSerializer(serializers.Serializer):
    """
    value serializer the inner most of the payload
    """
    item = serializers.CharField()
    verb = serializers.CharField()
    reaction_type = serializers.CharField()
    created_time = serializers.IntegerField(
        validators=[MinValueValidator(0), MaxValueValidator(4086831600)]
    )  # Limit the maximum epoch to 2099 July 4th 7:00AM
    post_id = serializers.CharField(max_length=40)
    from = FromSerializer()
    parent_id = serializers.CharField()

    def validate(self, attrs):
        """
        `from` is a python reserved word the add _ to distinguish it from them
        :param attrs:
        :return:
        """
        from_ = attrs.get('from')
        pass

    def create(self, validated_data):
        pass

    def update(self, instance, validated_data):
        pass

尝试:

ffrom = FromSerializer(source='from')

不起作用

尝试2:

class FacebookReactionSerializer(serializers.Serializer):
    """
    value serializer the inner most of the payload
    """
    item = serializers.CharField()
    verb = serializers.CharField()
    reaction_type = serializers.CharField()
    created_time = serializers.IntegerField(
        validators=[MinValueValidator(0), MaxValueValidator(4086831600)]
    )  # Limit the maximum epoch to 2099 July 4th 7:00AM
    post_id = serializers.CharField(max_length=40)
    from_key = FromSerializer()
    parent_id = serializers.CharField()

    def to_representation(self, instance):
        """
        https://stackoverflow.com/questions/47630356/using-the-reserved-word-class-as-field-name-in-django-and-django-rest-framewor
        :param instance:
        :return:
        """
        data = super().to_representation(instance)
        keys = list(data.keys())
        keys.insert(keys.index('from_key'), 'from')
        keys.remove('from_key')
        from_key = data.pop('from_key')
        data.update({'from': from_key})
        response = OrderedDict((k, data[k]) for k in keys)
        return response

    def create(self, validated_data):
        pass

    def update(self, instance, validated_data):
        pass

Testcase失败此处是断点

(Pdb) serializer
FacebookReactionSerializer(data={'item': 'reaction', 'verb': 'add', 'reaction_type': 'like', 'created_time': 1516183830, 'post_id': '1331351323541869_1844740022202994', 'from': {'name': 'Krittuch Onnom', 'id': '1639217166122728'}, 'parent_id': '1331351323541869_1844740022202994'}):
    item = CharField()
    verb = CharField()
    reaction_type = CharField()
    created_time = IntegerField(validators=[<rest_framework.compat.MinValueValidator object>, <rest_framework.compat.MaxValueValidator object>])
    post_id = CharField(max_length=40)
    from_key = FromSerializer():
        name = CharField()
        id = CharField()
    parent_id = CharField()
(Pdb) serializer.errors
*** AssertionError: You must call `.is_valid()` before accessing `.errors`.
(Pdb) serializer.is_valid()
False
(Pdb) serializer.errors
{'from_key': ['This field is required.']}

尝试3:
同时添加“”_声明的\u字段['from\u key']

class FacebookReactionSerializer(serializers.Serializer):
    item = serializers.CharField()
    verb = serializers.CharField()
    reaction_type = serializers.CharField()
    created_time = serializers.IntegerField(
        validators=[MinValueValidator(0), MaxValueValidator(4086831600)]
    )  # Limit the maximum epoch to 2099 July 4th 7:00AM
    post_id = serializers.CharField(max_length=40)
    from_key = FromSerializer()
    parent_id = serializers.CharField()

    def to_representation(self, instance):
        data = super().to_representation(instance)
        keys = list(data.keys())
        keys.insert(keys.index('from_key'), 'from')
        keys.remove('from_key')
        from_key = data.pop('from_key')
        data.update({'from': from_key})
        response = OrderedDict((k, data[k]) for k in keys)
        return response

    def create(self, validated_data):
        pass

    def update(self, instance, validated_data):
        pass

FacebookReactionSerializer._declared_fields["from"] = serializers.CharField(source="from_key")

调试线路:

(Pdb) serializer.is_valid()
False
(Pdb) serializer.errors
{'from_key': ['This field is required.'], 'from': ['Not a valid string.']}

我快到了,但这还不够

尝试4.1:

不工作。保持相同的错误。 from_key 仍然存在。我从 child 序列化程序。我必须使用 FromSerializer 不 CharField .

    class FacebookReactionSerializer(serializers.Serializer):
    """
    value serializer the inner most of the payload
    """
    item = serializers.CharField()
    verb = serializers.CharField()
    reaction_type = serializers.CharField()
    created_time = serializers.IntegerField(
        validators=[MinValueValidator(0), MaxValueValidator(4086831600)]
    )  # Limit the maximum epoch to 2099 July 4th 7:00AM
    post_id = serializers.CharField(max_length=40)
    from_key = FromSerializer()
    parent_id = serializers.CharField()

    def create(self, validated_data):
        pass

    def update(self, instance, validated_data):
        pass


FacebookReactionSerializer._declared_fields["from"] = FromSerializer(source="from_key")

我可以添加 从…起 现在作为一把钥匙。但它不会删除 from\U键 从验证逻辑中退出

(Pdb) serializer
FacebookReactionSerializer(data={'item': 'reaction', 'verb': 'add', 'reaction_type': 'like', 'created_time': 1516183830, 'post_id': '1331351323541869_1844740022202994', 'from': {'name': 'Krittuch Onnom', 'id': '1639217166122728'}, 'parent_id': '1331351323541869_1844740022202994'}):
    item = CharField()
    verb = CharField()
    reaction_type = CharField()
    created_time = IntegerField(validators=[<rest_framework.compat.MinValueValidator object>, <rest_framework.compat.MaxValueValidator object>])
    post_id = CharField(max_length=40)
    from_key = FromSerializer():
        name = CharField()
        id = CharField()
    parent_id = CharField()
    from = FromSerializer(source='from_key'):
        name = CharField()
        id = CharField()
(Pdb) serializer.is_valid()
False
(Pdb) serializer.errors
{'from_key': ['This field is required.']}

问题:
您的解决方法是什么 从…起 (保留字)是 key 这个键是python类属性吗?

1 回复 | 直到 6 年前

joe 6 年前

@塞萨尔非常感谢!
解决方案非常简单!早期我很困惑。因为给定的解决方案使用 ModelSerializer 所以你必须 fields 以及与模型特性的耦合。

在我的例子中是赤裸裸的平原 Serializer 我什么都不需要。

从现在起,我将通过 序列化程序 班

class FacebookReactionSerializer(serializers.Serializer):
    """
    value serializer the inner most of the payload
    """
    item = serializers.CharField()
    verb = serializers.CharField()
    reaction_type = serializers.CharField()
    created_time = serializers.IntegerField(
        validators=[MinValueValidator(0), MaxValueValidator(4086831600)]
    )  # Limit the maximum epoch to 2099 July 4th 7:00AM
    post_id = serializers.CharField(max_length=40)
    parent_id = serializers.CharField()

    def create(self, validated_data):
        pass

    def update(self, instance, validated_data):
        pass


FacebookReactionSerializer._declared_fields["from"] = FromSerializer()

这是我的调试行

(Pdb) serializer
FacebookReactionSerializer(data={'item': 'reaction', 'verb': 'add', 'reaction_type': 'like', 'created_time': 1516183830, 'post_id': '1331351323541869_1844740022202994', 'from': {'name': 'Krittuch Onnom', 'id': '1639217166122728'}, 'parent_id': '1331351323541869_1844740022202994'}):
    item = CharField()
    verb = CharField()
    reaction_type = CharField()
    created_time = IntegerField(validators=[<rest_framework.compat.MinValueValidator object>, <rest_framework.compat.MaxValueValidator object>])
    post_id = CharField(max_length=40)
    parent_id = CharField()
    from = FromSerializer():
        name = CharField()
        id = CharField()
(Pdb) serializer.is_valid()
True