在Django Rest Framework中序列化查询集

Question

我正在尝试把一组对象转换成可以存储或传输的格式。我定义了一个视图方法：

@csrf_exempt
def venue_list(request, user_id):
    """
    Check that the user is requesting his own venues.
    """
    profile = get_profile_for_user_if_match(request.user, user_id)

    if profile is None:
        return HttpResponse(status=status.HTTP_401_UNAUTHORIZED)

    venues = profile.venue_set.all()
    serializer = VenueSerializer(venues)

    return JSONResponse(serializer.data)

这个方法接收一个 user_id 参数，用来判断用户是否有权限访问这些数据，然后它会获取要返回的对象集合，但现在它不工作。

问题在于，它试图直接对这个集合进行转换，而不是对里面的每个对象进行转换，因此出现了这个错误信息：

Traceback:
File "/Users/mariopersonal/Documents/dev/offers/project/offers/venv/lib/python2.7/site-packages/django/core/handlers/base.py" in get_response
  111.                     response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/Users/mariopersonal/Documents/dev/offers/project/offers/venv/lib/python2.7/site-packages/django/views/decorators/csrf.py" in wrapped_view
  57.         return view_func(*args, **kwargs)
File "/Users/mariopersonal/Documents/dev/offers/project/offers/wsgi/openshift/business/restful/views/venueViews.py" in venue_list
  22.     return JSONResponse(serializer.data)
File "/Users/mariopersonal/Documents/dev/offers/project/offers/venv/lib/python2.7/site-packages/rest_framework/serializers.py" in data
  572.                 self._data = self.to_native(obj)
File "/Users/mariopersonal/Documents/dev/offers/project/offers/venv/lib/python2.7/site-packages/rest_framework/serializers.py" in to_native
  351.             value = field.field_to_native(obj, field_name)
File "/Users/mariopersonal/Documents/dev/offers/project/offers/venv/lib/python2.7/site-packages/rest_framework/fields.py" in field_to_native
  336.         return super(WritableField, self).field_to_native(obj, field_name)
File "/Users/mariopersonal/Documents/dev/offers/project/offers/venv/lib/python2.7/site-packages/rest_framework/fields.py" in field_to_native
  207.             value = get_component(value, component)
File "/Users/mariopersonal/Documents/dev/offers/project/offers/venv/lib/python2.7/site-packages/rest_framework/fields.py" in get_component
  58.         val = getattr(obj, attr_name)

Exception Type: AttributeError at /business/api/venues/1
Exception Value: 'QuerySet' object has no attribute 'name'

我该怎么做才能正确处理这个问题呢？

谢谢。

Answer 1

如果你想把一组对象或者查询集转换成可以存储或传输的格式，而不是单个对象，你需要在创建序列化器的时候加上 many=True 这个参数。所以在你的情况下，可以试试这样做：

...
venues = profile.venue_set.all()
serializer = VenueSerializer(venues, many=True)
...