如何检查模型是否在模型外键集中？ Django，django 休息框架

Question

我有一个房间模型，它与场地有多对一的关系。

一个场所可以有多个房间。

我正在尝试在我的休息框架中设置我的 http 方法，这样当我添加权限时一切正常。

所以如果说有人想从场地中删除房间，我必须确保 1 该人有权访问该场所 2 那个房间附属于那个场地

我想要场地模型然后获取场地模型 room_set 并检查 room_set 以查看是否存在具有我要删除的模型的房间主键的房间。

我目前拥有的：

class GetEditDeleteVenueRoom(APIView):

    def get(self, request, *args, **kwargs):
        pass

    def post(self, request, *args, **kwargs):
        print('wait its over here')



    def delete(self, request, *args, **kwargs):
        venuepk = kwargs.get('venuepk', None)
        venue = get_object_or_404(Venue, pk=venuepk)
        venuerooms = venue.room_set
        print(venuerooms)
        return Response({})

我希望我可以只对会场房间进行交互并检查会场房间中的每个对象，但我有一种强烈的感觉它不会工作，因为 venerooms 不是 python 对象？也许是。我将在执行 for 循环后更新这个问题，或者如果我发现一切正常，我可能会删除它。

我的问题是如何设置房间并查看是否有我正在搜索的房间 pk 的房间。

正如我所料，我在尝试的代码中遇到了错误：

def delete(self, request, *args, **kwargs):
    venuepk = kwargs.get('venuepk', None)
    venue = get_object_or_404(Venue, pk=venuepk)
    venuerooms = venue.room_set
    roompk = kwargs.get('roompk')
    roomobject = None
    for room in venuerooms:
        if room.pk == roompk:
            roomobject = room
    roomobject.delete()

    print(venuerooms)
    return Response({})

我得到的错误：

File "/home/rickus/Documents/softwareProjects/211hospitality/suitsandtables/backend/virtualsuits/suitsandtables/venues/views.py", line 125, in delete
    for room in venuerooms:
TypeError: 'RelatedManager' object is not iterable

有什么想法可以做吗？

新编辑：

所以我实施了下面的答案并将 all() 添加到我的 venerooms 定义

但是现在我有一个新的错误。这个没有意义，因为我显然覆盖了 for 循环中的 None 属性。

def delete(self, request, *args, **kwargs):
        venuepk = kwargs.get('venuepk', None)
        venue = get_object_or_404(Venue, pk=venuepk)
        venuerooms = venue.room_set.all()
        roompk = kwargs.get('roompk')
        roomobject = None
        for room in venuerooms:
            if room.pk == roompk:
                print(room)
                roomobject = room
        roomobject.delete()

        print(venuerooms)
        return Response({})

错误：

File "/home/rickus/Documents/softwareProjects/211hospitality/suitsandtables/backend/virtualsuits/suitsandtables/venues/views.py", line 129, in delete
    roomobject.delete()
AttributeError: 'NoneType' object has no attribute 'delete'
[14/Mar/2018 20:01:53] "DELETE /api/suitsadmin/venue/1/room/15 HTTP/1.1

Answer 1

添加您的模型来帮助解决问题....但这是您访问 room_set

的方式

def delete(self, request, *args, **kwargs):
    venuepk = kwargs.get('venuepk', None)
    venue = get_object_or_404(Venue, pk=venuepk)
    roompk = kwargs.get('roompk')
    room = venue.room_set.filter(pk=roompk)
    room.delete()
    return Response({})

Answer 2

所以我最终这样做了：

一旦我在 roomset 中找到房间对象，就抓取它。通过查询房间对象的数据库。虽然我对这个答案不满意。正如我想象的那样 room_set 已经可以访问房间对象了吗？我不能就这样删除它吗？如果可以的话，我会很感激比我更好的答案。不管这是我所做的。

 def delete(self, request, *args, **kwargs):
        venuepk = kwargs.get('venuepk', None)
        venue = get_object_or_404(Venue, pk=venuepk)
        venuerooms = venue.room_set.all()
        roompk = kwargs.get('roompk')
        roomobject = None
        for room in venuerooms:
            if room.pk == roompk:
               roomobject = Room.objects.get(pk=roompk)
               roomobject.delete()
               return Response({})

        return Response(status.HTTP_404_NOT_FOUND)

如何检查模型是否在模型外键集中？ Django，django 休息框架

how to check if a model is in a models foriegn key set? Django, django rest framework

django

django-related-manager

django-rest-framework