Question

我正试图通过Django从我的应用程序中取出。问题是当我通过序列化程序调用Order Detail时，我收到此错误：

TypeError at /api/customer/order/latest/
Object of type 'Product' is not JSON serializable
Request Method: GET
Request URL:    http://localhost:8000/api/customer/order/latest/?access_token=XXXXXXXXXXXXXXXXXXXXXXXXXXXX
Django Version: 1.10
Exception Type: TypeError
Exception Value:    
Object of type 'Product' is not JSON serializable

我从这个模型中提取数据：

class OrderDetail(models.Model):
    order = models.ForeignKey(Order, related_name='order_details')
    product_size = models.ForeignKey(ProductSize)
    quantity = models.IntegerField()
    sub_total = models.FloatField()

    def __str__(self):
        return str(self.id)

# references Prodcut and allows old code to work.
    @property
    def product(self):
        return self.product_size.product

这就是被拉动的内容：

'order_details': [OrderedDict([('id', 68),
                                ('product_size', 44),
                                ('quantity', 1),
                                ('sub_total', 20.0),
                                ('product', <Product: Bacon Burger - withDrink>)])],
 'status': 'Your Order Is Being Picked Right Off The Plant!',
 'total': 20.0}
request 
<WSGIRequest: GET '/api/customer/order/latest/?access_token=XXXXXXXXXXXXXXXXXXXXXXXXXXXX'>

串行器：

class OrderDetailSerializer(serializers.ModelSerializer):

    class Meta:
        model = OrderDetail
        fields = ("id", "product_size", "quantity", "sub_total", "product")


class OrderSerializer(serializers.ModelSerializer):
    customer = OrderCustomerSerializer()
    driver = OrderDriverSerializer()
    restaurant = OrderRestaurantSerializer()
    order_details = OrderDetailSerializer(many = True)
    status = serializers.ReadOnlyField(source= "get_status_display")

    class Meta:
        model = Order
        fields = ("id", "customer", "restaurant", "driver", "order_details", "total", "status", "address")

详情功能：

def customer_get_latest_order(request):
    access_token = AccessToken.objects.get(token = request.GET.get("access_token"),
    expires__gt = timezone.now())

    customer = access_token.user.customer
    order = OrderSerializer(Order.objects.filter(customer = customer).last()).data

    return JsonResponse({"order": order})

我不确定需要做什么。

Answer 1

由于db.users.aggregate([ { $lookup:{ // lookup assigned tickets from:'tickets', localField:'assignedTickets', foreignField:'_id', as:'assigned', } }, { $lookup:{ // lookup resolved tickets from:'tickets', localField:'resolvedTickets', foreignField:'_id', as:'resolved', } }, { $project:{ "tickets":{ // merge all tickets into one single array $concatArrays:[ "$assigned", "$resolved" ] } } }, { $unwind:'$tickets' // flatten the 'tickets' array into separate documents }, { $group:{ // group by 'createdAt' and 'assignee_id' _id:{ groupDate:{ $dateFromParts:{ year:{ $year:'$tickets.createdAt' }, month:{ $month:'$tickets.createdAt' }, day:{ $dayOfMonth:'$tickets.createdAt' }, }, }, userId:'$tickets.assignee_id', }, assignedCount:{ // get the count of assigned tickets $sum:{ $cond:[ { // by checking the 'type' field for a value of 'assigned' $eq:[ '$tickets.type', 'assigned' ] }, 1, // if matching count 1 0 // else 0 ] } }, resolvedCount:{ $sum:{ $cond:[ { // by checking the 'type' field for a value of 'resolved' $eq:[ '$tickets.type', 'resolved' ] }, 1, // if matching count 1 0 // else 0 ] } }, }, }, { $sort:{ // sort by 'groupDate' descending '_id.groupDate':-1 }, }, { $group:{ _id:'$_id.userId', // group again but only by userId data:{ $push:{ // create an array groupDate:'$_id.groupDate', assignedCount:{ $sum:'$assignedCount' }, resolvedCount:{ $sum:'$resolvedCount' } } } } } ])模型的product属性返回OrderDetail个对象，因此在响应过程中无法序列化。

要解决此问题，您只需返回Product：

即可

product.id

或者，如果您需要回复产品的详细信息，则应在class OrderDetail(models.Model): order = models.ForeignKey(Order, related_name='order_details') product_size = models.ForeignKey(ProductSize) quantity = models.IntegerField() sub_total = models.FloatField() def __str__(self): return str(self.id) @property def product(self): return self.product_size.product.id中添加一个嵌套的序列化程序：

OrderDetailSerializer

Answer 2

您需要为在OrderDetail模型中声明的product属性创建序列化程序。如果不这样做，它将给出此错误，因为product属性返回Product类的对象，并且它不知道如何序列化它。创建序列化程序后，请执行以下操作

class OrderDetailSerializer(serializers.ModelSerializer):
    product=ProductSerializer(read_only=True, many=False)//you need to do this
    class Meta:
        model = OrderDetail
        fields = ("id", "product_size", "quantity", "sub_total", "product")

“Product”类型的对象不是JSON可序列化的

2 个答案: