CreateModelMixin TypeError: init() takes 1 positional argument but 2 were given

Question

I'm trying to insert a new row into a 2 column table where one column references the authenticated user (model references user model via a FK) and the other being a variable passed through the url.

urls.py


url('^(?P<update>-?\d+.?\d+)/$', views.UpdateViewSet)

views.py


class UpdateViewSet(mixins.CreateModelMixin,viewsets.GenericViewSet):
    permission_classes = (IsAuthenticated,)  
    serializer_class = serializers.UpdateSerializer
    def create(self,request,*args, **kwargs):
        update = self.kwargs['update']
        return self.create(user=self.request.user,update=update)

Traceback

 File "\Backend\env\lib\site-packages\django\core\handlers\exception.py", line 34, in inner
    response = get_response(request)
  File "\Backend\env\lib\site-packages\django\core\handlers\base.py", line 115, in _get_response
    response = self.process_exception_by_middleware(e, request)
  File "\Backend\env\lib\site-packages\django\core\handlers\base.py", line 113, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
TypeError: __init__() takes 1 positional argument but 2 were given

class Update(models.Model):
    user = models.ForeignKey(CustomUser, on_delete=models.CASCADE)
    update = models.DecimalField(decimal_places=5,max_digits=6)

It may help you https://learnbatta.com/blog/viewsets-in-django-rest-framework-83/ — anjaneyulubatta505, Jun 13 '19 at 06:19

score 2 · Accepted Answer · edited Jun 20 '20 at 09:12

2

Since you are using class-based views--[Django Doc], you should've call as_view()--[Django Doc]

url('^(?P<update>-?\d+.?\d+)/$', views.UpdateViewSet.as_view({"post":"create"}))

Update-1

Change your view as below,

from rest_framework.response import Response


class UpdateViewSet(mixins.CreateModelMixin, viewsets.GenericViewSet):
    permission_classes = (IsAuthenticated,)
    serializer_class = serializers.UpdateSerializer

    def create(self, request, *args, **kwargs):
        update_instance = Update.objects.create(user=request.user, update=self.kwargs['update'])
        return Response(self.get_serializer(update_instance).data)

edited Jun 20 '20 at 09:12

Community

1
1

answered Jun 13 '19 at 06:18

JPG

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TypeError: create() missing 1 required positional argument: 'request' – Joshua Jun 13 '19 at 06:19
I fixed that as well, now I'm seeing TypeError: create() missing 1 required positional argument: 'request' – Joshua Jun 13 '19 at 06:22
What are you trying to do with `self.create(user=self.request.user,update=update)` line of code? Can you clarify that? – JPG Jun 13 '19 at 06:27
The Update model has two fields, one is a FK to the User model and the other is the update value. I'm trying to insert the record with authenticated user and the update value. – Joshua Jun 13 '19 at 06:32
can you add that model? – JPG Jun 13 '19 at 06:34
Updated. It's just a normal 2 field model. – Joshua Jun 13 '19 at 06:36
check my **`Update-1`** section. Hope that helps you. – JPG Jun 13 '19 at 06:39

score 1 · Answer 2 · answered Jun 13 '19 at 06:19

I think you are configuring the url wrongly, do like this:

from rest_framework.routers import DefaultRouter

router = DefaultRouter()
router.register(r'update', views.UpdateViewSet, basename='update')
urlpatterns = router.urls

Or

 url(r'^(?P<update>-?\d+.?\d+)/$', views.UpdateViewSet.as_view(actions={'post': 'create'}))

CreateModelMixin TypeError: __init__() takes 1 positional argument but 2 were given

2 Answers2

Update-1

CreateModelMixin TypeError: init() takes 1 positional argument but 2 were given