Question

当我尝试为我的用户添加汽车时，这就是正在发生的事情

 "username": [
"A user with that username already exists."]

这是我的模型，我使用的是Django auth用户模型有我的模特

class Car(models.Model): 
"""
CAR Table with a ForeingKey from USER Table

"""
user = models.ForeignKey(User, related_name='cars')
model = models.CharField(max_length=50)
color = models.CharField(max_length=20)
year = models.IntegerField()
seats = models.IntegerField()


def __unicode__(self):
    return u'%d: %s: %s: %d' % (self.id, self.model, self.color, self.year)

我的序列化工具

class CarSerializer(serializers.ModelSerializer):
class Meta:
    model = Car
    fields = (
        'model', 
        'color', 
        'seats'
        )      

class AddCarSerializer(serializers.ModelSerializer):
car = CarSerializer()
class Meta:
    model = User
    fields = (
        'username',
        'car'
        )

这是我的观点

class AddCarForUser(APIView):
authentication_classes = (TokenAuthentication,)
permission_classes = (IsAuthenticated,)

def put(self, request):
    car = AddCarSerializer(data = request.data)
    car.is_valid(raise_exception = True)
    car.save()
    return Response(status=status.HTTP_201_CREATED)

这就是我在Put请求中发送的内容

{
"username": "root",
"car": {
    "model": "Seat Ibiza",
    "color": "Verde",
    "seats": "4" 
}}

Answer 1

您的代码无效，因为您使用serializer.ModelSerializer且username类的User属性必须是唯一的，这就是为什么它无法验证它。要解决此问题，请按照以下步骤操作。

更新序列化程序AddCarSerializer。我们添加了一个自定义字段username来处理在没有唯一的情况下传递的用户名，只是一个简单的CharField。我们添加create函数，因为嵌套的序列化程序无法处理创建或更新框：

class AddCarSerializer(serializers.Serializer):
    # add username custom field
    username = serializers.CharField()
    car = CarSerializer()

    class Meta():
        fields = (
            'username',
            'car'
        )

    def create(self, validated_data):
        """ Add car to an user
        """
        tmp_car = validated_data.pop('car')
            user = User.objects.get(username=validated_data['username'])
        car = Car.objects.create(
            user=user,
            model=tmp_car['model'],
            color=tmp_car['color'],
            seats=tmp_car['seats'],
        )

        return car

更新您的观点：

class AddCarForUser(APIView):

    def put(self, request):
        serializer = AddCarSerializer(data = request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(status=status.HTTP_201_CREATED)
        return Response(status=status.HTTP_400_BAD_REQUEST)

更新您的Car模型，因为当我们向用户添加汽车时，year属性不存在，然后添加null=True：

class Car(models.Model):
    user = models.ForeignKey(User, related_name='cars')
    model = models.CharField(max_length=50)
    color = models.CharField(max_length=20)
    year = models.IntegerField(null=True)
    seats = models.IntegerField()

它应该有效。不要忘记处理错误，就像通过的用户名不存在一样。

如何使用Django Rest Framework向用户添加汽车

1 个答案: