Django rest框架，在创建多对多时获得AttributeError

我尝试通过重写.create（）方法添加订单和产品：

但我犯了这个错误：

试图获取序列化程序

OrderCreateSerializer

上的字段

product

的值时，获取了AttributeError。 序列化程序字段的名称可能不正确，并且与

Order

实例上的任何属性或键都不匹配。 原始异常文本为：“订单”对象没有属性“产品”

回溯：

Traceback (most recent call last):
    File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/core/handlers/exception.py", line 41, in inner
    response = get_response(request)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/core/handlers/base.py", line 187, in _get_response
    response = self.process_exception_by_middleware(e, request)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/core/handlers/base.py", line 185, in _get_response
    response = wrapped_callback(request, *callback_args, 
**callback_kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/views/decorators/csrf.py", line 58, in wrapped_view
    return view_func(*args, **kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/views/generic/base.py", line 68, in view
    return self.dispatch(request, *args, **kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/views.py", line 483, in dispatch
    response = self.handle_exception(exc)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/views.py", line 443, in handle_exception
    self.raise_uncaught_exception(exc)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/views.py", line 480, in dispatch
    response = handler(request, *args, **kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/generics.py", line 192, in post
    return self.create(request, *args, **kwargs)
  File "/home/denis/Projects/lunch_order/apps/api/views.py", line 24, 
in create
    headers = self.get_success_headers(serializer.data)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/serializers.py", line 560, in data
    ret = super(Serializer, self).data
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/serializers.py", line 262, in data
    self._data = self.to_representation(self.instance)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/serializers.py", line 514, in 
to_representation
    attribute = field.get_attribute(instance)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/relations.py", line 177, in get_attribute
    return super(RelatedField, self).get_attribute(instance)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/fields.py", line 462, in get_attribute
     raise type(exc)(msg)
AttributeError: Got AttributeError when attempting to get a value for 
field `product` on serializer `OrderCreateSerializer`.
The serializer field might be named incorrectly and not match any 
attribute or key on the `Order` instance.
Original exception text was: 'Order' object has no attribute 
'product'.

class OrderCreateAPIView(CreateAPIView):
    model = Order
    serializer_class = OrderCreateSerializer

class Order(models.Model):
    owner = models.ForeignKey(User, on_delete=models.CASCADE)
    date = models.DateTimeField(auto_now_add=True)

class Product(models.Model):
    order = models.ManyToManyField(Order, blank=True)
    title = models.CharField(max_length=120)
    manufacturer = models.CharField(max_length=120)
    price = models.IntegerField()  

但是，订单和产品是创造出来的

视图：

Traceback (most recent call last):
    File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/core/handlers/exception.py", line 41, in inner
    response = get_response(request)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/core/handlers/base.py", line 187, in _get_response
    response = self.process_exception_by_middleware(e, request)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/core/handlers/base.py", line 185, in _get_response
    response = wrapped_callback(request, *callback_args, 
**callback_kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/views/decorators/csrf.py", line 58, in wrapped_view
    return view_func(*args, **kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/views/generic/base.py", line 68, in view
    return self.dispatch(request, *args, **kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/views.py", line 483, in dispatch
    response = self.handle_exception(exc)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/views.py", line 443, in handle_exception
    self.raise_uncaught_exception(exc)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/views.py", line 480, in dispatch
    response = handler(request, *args, **kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/generics.py", line 192, in post
    return self.create(request, *args, **kwargs)
  File "/home/denis/Projects/lunch_order/apps/api/views.py", line 24, 
in create
    headers = self.get_success_headers(serializer.data)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/serializers.py", line 560, in data
    ret = super(Serializer, self).data
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/serializers.py", line 262, in data
    self._data = self.to_representation(self.instance)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/serializers.py", line 514, in 
to_representation
    attribute = field.get_attribute(instance)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/relations.py", line 177, in get_attribute
    return super(RelatedField, self).get_attribute(instance)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/fields.py", line 462, in get_attribute
     raise type(exc)(msg)
AttributeError: Got AttributeError when attempting to get a value for 
field `product` on serializer `OrderCreateSerializer`.
The serializer field might be named incorrectly and not match any 
attribute or key on the `Order` instance.
Original exception text was: 'Order' object has no attribute 
'product'.

class OrderCreateAPIView(CreateAPIView):
    model = Order
    serializer_class = OrderCreateSerializer

class Order(models.Model):
    owner = models.ForeignKey(User, on_delete=models.CASCADE)
    date = models.DateTimeField(auto_now_add=True)

class Product(models.Model):
    order = models.ManyToManyField(Order, blank=True)
    title = models.CharField(max_length=120)
    manufacturer = models.CharField(max_length=120)
    price = models.IntegerField()  

型号：

Traceback (most recent call last):
    File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/core/handlers/exception.py", line 41, in inner
    response = get_response(request)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/core/handlers/base.py", line 187, in _get_response
    response = self.process_exception_by_middleware(e, request)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/core/handlers/base.py", line 185, in _get_response
    response = wrapped_callback(request, *callback_args, 
**callback_kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/views/decorators/csrf.py", line 58, in wrapped_view
    return view_func(*args, **kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/django/views/generic/base.py", line 68, in view
    return self.dispatch(request, *args, **kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/views.py", line 483, in dispatch
    response = self.handle_exception(exc)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/views.py", line 443, in handle_exception
    self.raise_uncaught_exception(exc)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/views.py", line 480, in dispatch
    response = handler(request, *args, **kwargs)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/generics.py", line 192, in post
    return self.create(request, *args, **kwargs)
  File "/home/denis/Projects/lunch_order/apps/api/views.py", line 24, 
in create
    headers = self.get_success_headers(serializer.data)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/serializers.py", line 560, in data
    ret = super(Serializer, self).data
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/serializers.py", line 262, in data
    self._data = self.to_representation(self.instance)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/serializers.py", line 514, in 
to_representation
    attribute = field.get_attribute(instance)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/relations.py", line 177, in get_attribute
    return super(RelatedField, self).get_attribute(instance)
  File "/home/denis/Projects/lunch_order/.venv/lib/python3.5/site- 
packages/rest_framework/fields.py", line 462, in get_attribute
     raise type(exc)(msg)
AttributeError: Got AttributeError when attempting to get a value for 
field `product` on serializer `OrderCreateSerializer`.
The serializer field might be named incorrectly and not match any 
attribute or key on the `Order` instance.
Original exception text was: 'Order' object has no attribute 
'product'.

class OrderCreateAPIView(CreateAPIView):
    model = Order
    serializer_class = OrderCreateSerializer

class Order(models.Model):
    owner = models.ForeignKey(User, on_delete=models.CASCADE)
    date = models.DateTimeField(auto_now_add=True)

class Product(models.Model):
    order = models.ManyToManyField(Order, blank=True)
    title = models.CharField(max_length=120)
    manufacturer = models.CharField(max_length=120)
    price = models.IntegerField()  

编辑 更改代码后出现该错误：

TypeError: 
<django.db.models.fields.related_descriptors.
create_forward_many_to_many_manager.<locals>.ManyRelatedManager object 
at 0x7fe9981e0b70> is not JSON serializable

TypeError:
JSON不可序列化

默认情况下，许多字段的反向相关名称为

model\u set

，因此使用

source=product\u set

参数作为产品字段。另外，由于

product\u set

包含许多对象，因此此字段使用

many=True

：

class OrderCreateSerializer(ModelSerializer):
    product = PrimaryKeyRelatedField(source='product_set', many=True, queryset=Product.objects.all())

---

@DenisSvistunov也能展示一下你是如何发布产品的吗？它是这样的：

{“product”：[1,2]}

？我只需要添加一个产品，数据看起来像{“owner”：1，“product”：1}@DenisSvistunov manytomy字段意味着对象列表。如果您只需要添加一个对象，请使用

{“product”：[1]}

@neverwalkalkiner，谢谢您，我理解了，我添加了many=True并将我的请求更改为{“product”：[1]}并更改了订单。product_set.add（product[0]）。所有的工作都没有错误。谢谢你的帮助