1

我对 DRF 和一些序列化程序有一个奇怪的问题。

这是我的模型：

class Accommodation(models.Model):
    created = models.DateTimeField(auto_now_add=True)
    modified = models.DateTimeField(auto_now=True)
    product = models.OneToOneField(
        Product,
        on_delete=models.CASCADE,
        primary_key=True,
    )
    description = models.TextField(null=True, blank=True, verbose_name=_(u'Description'))
    shared_accommodation = models.BooleanField(default=False)
    accommodation_unit_quantity = models.PositiveSmallIntegerField(default=1,
                                                                verbose_name=_(u'Number of acommodation units '
                                                                              u'for this acommodation'))
    accommodation_unit_name = models.TextField(null=False, blank=False, verbose_name=_(u'Name for accommodation units '
                                                                                   u'for this accommodation'))

    class Meta:
        verbose_name_plural = _(u'Accommodations')

    def __unicode__(self):
        return u'{0} <{1}>'.format(self.product.name, self.product.school)

class Product(AbstractProduct):

    name = models.CharField(max_length=50, verbose_name=_(u'Name'))
    school = models.ForeignKey('school.School')
    levels = models.ManyToManyField('school.Level',verbose_name=_(u'Level'))
    age = IntegerRangeField(null=True)
    gender = models.CharField(choices=GENDER_CHOICES, max_length=1, null=True, blank=True, verbose_name=_(u'Gender'))
    num_sessions = models.PositiveSmallIntegerField(
        verbose_name=_(u'Number of sessions'),
        default=1,
        help_text=_(u"Number of sessions that the product has."),
    )
    school_category = models.ForeignKey(
        'school.Category',
        blank=True, null=True,
        verbose_name=_(u'Category')
    )
    addons = models.ManyToManyField('self',
        verbose_name=_(u'Administrators'),
        through='AddonInService',
        symmetrical=False,
        related_name='addon_can_be_used_in'
    )

    pay_option = models.CharField(choices=PAYMENT_OPTIONS, max_length=1, null=True, blank=True, verbose_name=_(u'Pay_option'), default='U')
    payment_type = models.CharField(choices=PAYMENT_TYPE, max_length=1, null=True, blank=True, verbose_name=_(u'pay_type'))
    payment_amount = models.FloatField(verbose_name=_(u'Amount'), default=0.0)

    objects = ProductManager()

    class Meta(AbstractProduct.Meta):
        verbose_name_plural = _(u'Products')

    def __unicode__(self):
        return self.name

如您所见，基本上，产品可以是住宿。这是序列化程序

class AccommodationSerializer(serializers.ModelSerializer):
    class Meta:
        model = Accommodation
        fields = [
            'description',
            'shared_accommodation',
            'accommodation_unit_quantity',
            'accommodation_unit_name',
        ]


class ProductAccommodationSerializer(ProductSerializer):

    accommodation = AccommodationSerializer()

    class Meta(ProductSerializer.Meta):
        fields = [
            'id',
            'structure',
            'upc',
            'title',
            'slug',
            'description',
            'rating',
            'date_created',
            'date_updated',
            'is_discountable',
            'name',
            'age',
            'gender',
            'num_sessions',
            'parent',
            'product_class',
            'school',
            'levels',
            'school_category',
            'addons',
            'color',
            'price',
            'all_prices',
            'variants',
            'pay_option',
            'payment_type',
            'payment_amount',
            'accommodation',
        ]

    def create(self, validated_data):
        accommodation_data = validated_data.pop('accommodation')

        levels = []
        if 'levels' in validated_data:
            levels = validated_data.pop('levels')

        product = Product.objects.create(**validated_data)
        school_accommodation, created = ProductClass.objects.get_or_create(name='School Accommodation')
        if created:
            product.product_class = school_accommodation
        for lev in levels:
            product.levels.add(lev)
        product.save()

        acc = AccommodationSerializer(product=product, **accommodation_data)
        acc.save()
        return product

class ProductSerializer(serializers.ModelSerializer):
    age = IntegerRangeField()
    addons = AddonSerializer(many=True, read_only=True)
    # Get the price for the Product, using the property in the Model
    price = serializers.DecimalField(required=False, max_digits=7,
                                 decimal_places=2, source='get_price',
                                 read_only=True)
    color = serializers.SerializerMethodField()

    all_prices = PriceSerializer(source='stockrecords', many=True,
                                   required=False)

    variants = VariantSerializer(many=True, source='children', required=False)

    class Meta:
        model = Product
        fields = [
            'id',
            'structure',
            'upc',
            'title',
            'slug',
            'description',
            'rating',
            'date_created',
            'date_updated',
            'is_discountable',
            'name',
            'age',
            'gender',
            'num_sessions',
            'parent',
            'product_class',
            'school',
            'levels',
            'school_category',
            'addons',
            'color',
            'price',
            'all_prices',
            'variants',
            'pay_option',
            'payment_type',
            'payment_amount'
        ]

执行一个简单的测试，我尝试创建一个住宿，我收到以下错误：

Traceback (most recent call last):
File "/home/internetmosquito/git/mvp_opencoast/opencoast_django/opencoast/applications/accommodation/tests/test_accommodations.py", line 165, in test_create_accommodation
response = self.client.post(url, data, format='json')
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/rest_framework/test.py", line 170, in post
path, data=data, format=format, content_type=content_type, **extra)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/rest_framework/test.py", line 92, in post
return self.generic('POST', path, data, content_type, **extra)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/django/test/client.py", line 380, in generic
return self.request(**r)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/rest_framework/test.py", line 159, in request
return super(APIClient, self).request(**kwargs)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/rest_framework/test.py", line 111, in request
request = super(APIRequestFactory, self).request(**kwargs)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/django/test/client.py", line 467, in request
six.reraise(*exc_info)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/django/core/handlers/base.py", line 149, in get_response
response = self.process_exception_by_middleware(e, request)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/django/core/handlers/base.py", line 147, in get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/django/views/decorators/csrf.py", line 58, in wrapped_view
return view_func(*args, **kwargs)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/rest_framework/viewsets.py", line 87, in view
return self.dispatch(request, *args, **kwargs)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/rest_framework/views.py", line 466, in dispatch
response = self.handle_exception(exc)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/rest_framework/views.py", line 463, in dispatch
response = handler(request, *args, **kwargs)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/rest_framework/mixins.py", line 21, in create
self.perform_create(serializer)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/rest_framework/mixins.py", line 26, in perform_create
serializer.save()
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/rest_framework/serializers.py", line 191, in save
self.instance = self.create(validated_data)
File "/home/internetmosquito/git/mvp_opencoast/opencoast_django/opencoast/applications/accommodation/serializers.py", line 77, in create
acc = AccommodationSerializer(product=product, **accommodation_data)
File "/home/internetmosquito/python_envs/opencoast_django/local/lib/python2.7/site-packages/rest_framework/serializers.py", line 95, in __init__
super(BaseSerializer, self).__init__(**kwargs)
TypeError: __init__() got an unexpected keyword argument 'product'

试图删除

产品=产品

从

acc = AccommodationSerializer(product=product, **accommodation_data)

但后来我得到了同样的错误，但使用“shared_accommodation”字段而不是产品

我在这里做错了什么？有任何想法吗？

编辑：添加 ProductSerializer，我错过了一个抱歉

第二次编辑：正如一些人所建议的，我已将产品字段添加到了住宿序列化器中：

class AccommodationSerializer(serializers.ModelSerializer):
    class Meta:
        model = Accommodation
        fields = [
            'product',
            'description',
            'shared_accommodation',
            'accommodation_unit_quantity',
            'accommodation_unit_name',
        ]

但是在尝试创建实例时，我收到以下错误：

{'accommodation': OrderedDict([('product', [u'This field is required.'])])}

有趣的是，如果我将产品添加到测试数据有效负载中（即使我在调用端点进行住宿时尚未创建产品，上面的错误也会消失）：

data = {
        "name": "Hotel Hudson",
        "slug": "hotel-hudson",
        "age": {'upper': 99, 'lower': 18},
        "school": school1.id,
        "levels": [school1.level_set.all()[0].id],
        "accommodation": {
            "product": 1,
            "description": "A very nice hotel",
            "shared_accommodation": False,
            "accommodation_unit_quantity": 1,
            "accommodation_unit_name": "Room",
            "accommodation_units": [
                {
                    'name': "Room-1",
                    'max_pax': 1,
                },
                {
                    'name': "Room-2",
                    'max_pax': 3,
                },
            ]
        },
    }

虽然这很有趣，但这显然不是我想要的……我不想在调用端点创建住宿时传递虚假的产品 ID……任何指针？

4

1 回答 1

3

使用该data字段将是正确的方法，因为 DRF 序列化器层次结构中的关键字不是通用的。如果您指定的字典有效，您可以使用（在调用之后）data创建模型实例。在创建模型之前，当然可以用更多的属性来扩充字典。但请注意，序列化程序仅使用在序列化程序字段中指定的属性。.save().is_valid()Meta.fields

这里是关键点，为什么你的方法根本不起作用：AccomodationSerializer.Meta.fields不包括product字段，如果你想创建一个模型，这是强制性的。

可以AccommodationSerializer从模型中读取，Accommodation或者出于某种原因想要发布模型的部分结构。但是如果要使用它来创建模型实例，则必须指定所有不可为空或具有默认值的字段。

而不是在AccommodationSerializer这里使用，你可以打电话：

    Accommodation.objects.create(product=product, **accommodation_data)

我试图建立一个最小的例子。希望这可以帮助。

模型.py：

class Owner(models.Model):

    owner_name = models.CharField(max_length=255)


class Product(models.Model):

    name = models.CharField(max_length=255)
    owner = models.OneToOneField(Owner)

序列化程序.py

class OwnerSerializer(serializers.ModelSerializer):

    class Meta:
        model = Owner
        fields = [
            'owner_name',
        ]

class ProductSerializer(serializers.ModelSerializer):

    owner = OwnerSerializer(read_only=True)

    class Meta:
        model = Product
        fields = [
            'owner',
            'name',
        ]


class ProductOwnerSerializer(serializers.ModelSerializer):

    product = ProductSerializer()

    class Meta:
        model = Owner
        fields = [
            'product',
            'owner_name',
        ]

    def create(self, validated_data):
        product_data = validated_data.pop('product')
        owner = Owner.objects.create(**validated_data)
        Product.objects.create(owner=owner, **product_data)
        return owner

我也同意 Jerzyk 的评论，我真的不喜欢Meta(Superclass), 对我来说似乎是一种反模式。

于 2016-07-09T16:46:56.013 回答