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Test of Django ProfileListView fails with ValueError: Cannot assign "<SimpleLazyObject:....>": "Profile.user" must be a "User" instance

I am a Django beginner and a SOF newbie, sorry if this question sounds a silly to some.
I am struggling with my integration tests.
In my app I have a one-to-one User/Profile relationship. I have a list view to show registered users' profile data:
class ProfileListView(views.ListView, LoginRequiredMixin):
model = Profile
template_name = 'registration/profile_list.html'
paginate_by = 8
def get_context_data(self, *, object_list=None, **kwargs):
context = super(ProfileListView, self).get_context_data()
# superuser raises DoesNotExist at /accounts/profiles/ as they are created with createsuperuser in manage.py
# hence are not assigned a profile automatically => create profile for them here
try:
context['current_profile'] = Profile.objects.get(pk=self.request.user.pk)
except ObjectDoesNotExist:
Profile.objects.create(user=self.request.user)
context['current_profile'] = Profile.objects.get(pk=self.request.user.pk)
# get all other users' profiles apart from staff and current user
regular_users = User.objects \
.filter(is_superuser=False, is_staff=False, is_active=True) \
.exclude(pk=self.request.user.pk)
context['non_staff_active_profiles'] = Profile.objects.filter(user__in=regular_users)
return context
I want to test the get_context_data() method to ensure it returns:
correct logged in user
correct queryset of non-staff profiles
My test breaks as soon as I try something like:
response = self.client.get('/accounts/profiles/')
I understand I need to pass user/profile data to the client but I could not figure out how to do that. It looks like it fails because of context['current_profile'] = Profile.objects.get(pk=self.request.user.pk) and I have no idea why.
The whole 'test' is below:
def test_view_get_context_data__should_return_correct_context(self):
new_user = User.objects.create_user(**self.VALID_USER_DATA_1)
# create profile
new_profile = Profile.objects.create(user=new_user)
# test profile
self.assertEqual(new_profile.user_id, new_user.pk)
response = self.client.get('/accounts/profiles/')
It fails with:
/home/kk/Documents/Github/Phonotheque/venv/bin/python /snap/pycharm-professional/280/plugins/python/helpers/pycharm/django_test_manage.py test Phonotheque.accounts_app.tests.views.test_ProfileListView.ProfilesListViewTests.test_view_get_context_data__should_return_correct_context /home/kk/Documents/Github/Phonotheque
Testing started at 15:54 ...
Found 1 test(s).
Creating test database for alias 'default'...
System check identified no issues (0 silenced).
/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/views/generic/list.py:91: UnorderedObjectListWarning: Pagination may yield inconsistent results with an unordered object_list: <class 'Phonotheque.accounts_app.models.Profile'> QuerySet.
return self.paginator_class(
Destroying test database for alias 'default'...
Error
Traceback (most recent call last):
File "/home/kk/Documents/Github/Phonotheque/Phonotheque/accounts_app/views.py", line 138, in get_context_data
context['current_profile'] = Profile.objects.get(pk=self.request.user.pk)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/db/models/manager.py", line 85, in manager_method
return getattr(self.get_queryset(), name)(*args, **kwargs)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/db/models/query.py", line 496, in get
raise self.model.DoesNotExist(
Phonotheque.accounts_app.models.Profile.DoesNotExist: Profile matching query does not exist.
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/home/kk/Documents/Github/Phonotheque/Phonotheque/accounts_app/tests/views/test_ProfileListView.py", line 65, in test_view_get_context_data__should_return_correct_context
response = self.client.get('/accounts/profiles/')
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/test/client.py", line 836, in get
response = super().get(path, data=data, secure=secure, **extra)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/test/client.py", line 424, in get
return self.generic(
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/test/client.py", line 541, in generic
return self.request(**r)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/test/client.py", line 810, in request
self.check_exception(response)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/test/client.py", line 663, in check_exception
raise exc_value
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/core/handlers/exception.py", line 55, in inner
response = get_response(request)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/core/handlers/base.py", line 197, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/views/generic/base.py", line 84, in view
return self.dispatch(request, *args, **kwargs)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/views/generic/base.py", line 119, in dispatch
return handler(request, *args, **kwargs)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/views/generic/list.py", line 174, in get
context = self.get_context_data()
File "/home/kk/Documents/Github/Phonotheque/Phonotheque/accounts_app/views.py", line 140, in get_context_data
Profile.objects.create(user=self.request.user)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/db/models/manager.py", line 85, in manager_method
return getattr(self.get_queryset(), name)(*args, **kwargs)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/db/models/query.py", line 512, in create
obj = self.model(**kwargs)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/db/models/base.py", line 541, in __init__
_setattr(self, field.name, rel_obj)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/db/models/fields/related_descriptors.py", line 338, in __set__
super().__set__(instance, value)
File "/home/kk/Documents/Github/Phonotheque/venv/lib/python3.8/site-packages/django/db/models/fields/related_descriptors.py", line 235, in __set__
raise ValueError(
ValueError: Cannot assign "<SimpleLazyObject: <django.contrib.auth.models.AnonymousUser object at 0x7f682f11e220>>": "Profile.user" must be a "User" instance.
Process finished with exit code 1
How do I simulate creation of multiple users/profiles, logging in of one of them and obtaining the relevant data?
Thanks a lot in advance.

It was quite a specific question and I very much doubt anyone ever will be looking at this answer but just in case:
def test_view_get_context_data__with__logged_in_user_should_return_correct_context(self):
user_data = {'username': 'BayHuy', 'password': '11111111', }
new_user = User.objects.create_user(**user_data)
new_profile = Profile.objects.create(user=new_user)
self.assertEqual(len(User.objects.all()), 1)
self.assertEqual(new_profile.user_id, new_user.pk)
self.assertEqual(len(Profile.objects.all()), 1)
self.client.login(**user_data)
response = self.client.get(reverse('profiles-list'))
self.assertEqual(
new_profile,
response.context_data['current_profile'])
self.assertEqual(
new_profile, response.context_data['current_profile'])
self.assertEqual(len(response.context_data['profile_list']), 1)

Problen with generating token in login

Hello I would like help I have been trying to learn how to create token with django rest framework and pyjwt
But whenever I do it when I am going to use login it gives me an error I would like to know if it is due to the code since I have seen several videos and I have the same code or it is due to something on my computer and if so, how could I solve it, the error is the next
Internal Server Error: /api/login
Traceback (most recent call last):
File "D:\Users\ferna\Documents\Cursos\Youtube\auth.env\lib\site-packages\django\core\handlers\exception.py", line 47, in inner
response = get_response(request)
File "D:\Users\ferna\Documents\Cursos\Youtube\auth.env\lib\site-packages\django\core\handlers\base.py", line 181, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "D:\Users\ferna\Documents\Cursos\Youtube\auth.env\lib\site-packages\django\views\decorators\csrf.py", line 54, in wrapped_view
return view_func(*args, **kwargs)
File "D:\Users\ferna\Documents\Cursos\Youtube\auth.env\lib\site-packages\django\views\generic\base.py", line 70, in view
return self.dispatch(request, *args, **kwargs)
File "D:\Users\ferna\Documents\Cursos\Youtube\auth.env\lib\site-packages\rest_framework\views.py", line 509, in dispatch
response = self.handle_exception(exc)
File "D:\Users\ferna\Documents\Cursos\Youtube\auth.env\lib\site-packages\rest_framework\views.py", line 469, in handle_exception
self.raise_uncaught_exception(exc)
File "D:\Users\ferna\Documents\Cursos\Youtube\auth.env\lib\site-packages\rest_framework\views.py", line 480, in raise_uncaught_exception
raise exc
File "D:\Users\ferna\Documents\Cursos\Youtube\auth.env\lib\site-packages\rest_framework\views.py", line 506, in dispatch
response = handler(request, *args, **kwargs)
File "D:\Users\ferna\Documents\Cursos\Youtube\auth\users\views.py", line 37, in post
token = jwt.encode(payload, 'secret', algorithm='HS256').decode('utf-8')
AttributeError: 'str' object has no attribute 'decode'
[07/May/2021 21:18:23] ←[35;1m"POST /api/login HTTP/1.1" 500 96900←[0m
the code for view it's
from rest_framework.views import APIView
from rest_framework.response import Response
from rest_framework.exceptions import AuthenticationFailed
from .serializers import UserSerializer
from .models import User
import jwt, datetime
# Create your views here.
class RegisterView(APIView):
def post(self, request):
serializer = UserSerializer(data=request.data)
serializer.is_valid(raise_exception=True)
serializer.save()
return Response(serializer.data)
class LoginView(APIView):
def post(self, request):
email = request.data['email']
password = request.data['password']
user = User.objects.filter(email=email).first()
if user is None:
raise AuthenticationFailed('User not found!')
if not user.check_password(password):
raise AuthenticationFailed('Incorrect password!')
payload = {
'id': user.id,
'exp': datetime.datetime.utcnow() + datetime.timedelta(minutes=60),
'iat': datetime.datetime.utcnow()
}
token = jwt.encode(payload, 'secret', algorithm='HS256').decode('utf-8')
response = Response()
response.set_cookie(key='jwt', value=token, httponly=True)
response.data = {
'jwt': token
}
return response

I found actual problem.
The package PyJWT changed return type of jwt.encode(...) with version 2. From now it returns string instead of byte string. Link
After that use these codes:
encoded = jwt.encode({"some": "payload"}, key, algorithm="HS256")
result = jwt.decode(encoded, key, algorithms="HS256")
instead of that this:
result = jwt.encode(payload, 'secret', algorithm='HS256').decode('utf-8')

Getting "Exception: You cannot access body after reading from request's data stream" while working with DRF and django-revproxy

I'm using django-revproxy and Django REST Framework in my project. And I'm exposing an API where users get analytics about their chatbots, and it works as the following:
The user send requests the analytics from the Django project
Django project, checks if the user is authenticated and owns that chatbot
if True it contacts another external service.
My urls.py:
# urls.py
urlpatterns = (
url(r'^analytics/(?P<path>.*)$', api.AnalyticsFunctionsProxyView.as_view()),
)
And in my view:
# views.py
from rest_framework.authentication import TokenAuthentication
from rest_framework_jwt.authentication import JSONWebTokenAuthentication
from rest_framework.permissions import IsAuthenticated
from revproxy.views import ProxyView
from .permissions import HasChatBotPermission
...
class AnalyticsFunctionsProxyView(ProxyView):
upstream = settings.ANALYTICS_FAAS_URL
def parse_body(self, request):
if isinstance(request, rest_framework.request.Request):
return request.data
return super(AnalyticsFunctionsProxyView, self).parse_body(request)
#classmethod
def as_view(cls, *args, **kwargs):
view = super(AnalyticsFunctionsProxyView, cls).as_view(*args, **kwargs)
view = permission_classes((IsAuthenticated, HasChatBotPermission,))(view)
view = authentication_classes([TokenAuthentication, JSONWebTokenAuthentication])(view)
view = api_view(['GET', 'POST'])(view)
return view
And my HasChatBotPermission permissions
#permissions.py
class HasChatBotPermission(permissions.BasePermission):
def has_permission(self, request, view):
try:
bot_name = request.data.get('name')
user = request.user
self.message = 'Permission denied for {}'.format(name)
return ChatBot.objects.filter(user=user, project_name=project_id).exists()
except Exception:
self.message = 'Permission denied, no project_id was defined!'
return False
When the view is called it raises this exception:
Traceback (most recent call last):
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/rest_framework/request.py", line 379, in __getattribute__
return super(Request, self).__getattribute__(attr)
AttributeError: 'Request' object has no attribute 'body'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/django/core/handlers/exception.py", line 42, in inner
response = get_response(request)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/django/core/handlers/base.py", line 187, in _get_response
response = self.process_exception_by_middleware(e, request)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/django/core/handlers/base.py", line 185, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/home/fcmam5/anaconda3/lib/python3.6/contextlib.py", line 52, in inner
return func(*args, **kwds)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/django/views/decorators/csrf.py", line 58, in wrapped_view
return view_func(*args, **kwargs)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/django/views/generic/base.py", line 68, in view
return self.dispatch(request, *args, **kwargs)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/rest_framework/views.py", line 477, in dispatch
response = self.handle_exception(exc)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/rest_framework/views.py", line 437, in handle_exception
self.raise_uncaught_exception(exc)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/rest_framework/views.py", line 474, in dispatch
response = handler(request, *args, **kwargs)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/rest_framework/decorators.py", line 52, in handler
return func(*args, **kwargs)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/django/views/generic/base.py", line 68, in view
return self.dispatch(request, *args, **kwargs)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/revproxy/views.py", line 204, in dispatch
proxy_response = self._created_proxy_response(request, path)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/revproxy/views.py", line 139, in _created_proxy_response
request_payload = request.body
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/rest_framework/request.py", line 383, in __getattribute__
return getattr(self._request, attr)
File "/home/fcmam5/dela3a/env/lib/python3.6/site-packages/django/http/request.py", line 264, in body
raise RawPostDataException("You cannot access body after reading from request's data stream")
django.http.request.RawPostDataException: You cannot access body after reading from request's data stream
The issue is caused by this line bot_name = request.data.get('name') in my permissions.py, when I pass a string directly it passes without any problems.
My question is:
How can I access the request body without having this error? Why I'm having this error?
Is there a better solution for checking the user permission with Django revproxy.
This is my first question in Stackoverflow, sorry if my question is not clea, and for my poor English :)

You're having this error because django-revproxy attempts to read the raw request body so it can create a proxy request to the upstream server.
However, with Django's (and WSGI's, and buffering) semantics, this isn't possible once you've accessed the request body as anything but a raw stream, which you do when you request.data.get('name'). This parses the request body as JSON, HTTP multipart, whatever, depending on DRF's request negotiation configuration, and consumes the stream.
There are two ways you could get around this, as far as I see:
pass bot_name somewhere else than the body; a query string parameter, an HTTP header, part of the URL, for instance, so you don't need to access the body, or
make the backend request yourself using requests instead of reverse-proxying (which is basically the same thing, but with added magic to try and copy the request through as-is).

Modify DRF Request objects for dispatch to other views

Context
AWS Elastic Beanstalk Worker tiers can be configured to accept a single AWS SQS queue automatically. Incoming messages on this queue can be routed to a single endpoint which some instance in the worker tier will respond to; they show up to the workers as POST events.
The software my workers are running is based on Django/DRF.
Goal
I want my worker tier instances to be able to handle more than one type of incoming event. Ideally, SQS could be configured to deliver the requests to more than one endpoint, but that appears to be impossible.
My implementation
class DispatchSerializer(serializers.Serializer):
"`to` is the name of the destination endpoint; `payload` is the data I want delivered"
to = serializers.CharField(
max_length=80,
)
payload = serializers.JSONField()
#api_view(http_method_names=['POST'])
#permission_classes([AllowAny])
def dispatch(request):
"""
Dispatch a request to a sibling endpoint.
"""
routing_table = {
... # this is specific to my application;
# it's just a dict of names to views
}
serializer = DispatchSerializer(data=request.data)
if serializer.is_valid(raise_exception=True):
to = serializer.validated_data['to']
try:
view = routing_table[to]
except KeyError:
raise Http404()
# https://github.com/encode/django-rest-framework/blob/master/rest_framework/request.py#L183-L187
request._full_data = serializer.validated_data['payload']
return view(request)
# If this returns other than 200, SQS simply re-attempts the request later.
# No returned data is preserved, so we might as well not return any.
return Response()
As you can see, I attempt to simply replace _full_data attribute of the request with the payload, so that the inner view sees only the data intended for it (which to the dispatch view is the payload).
The problem
This implementation doesn't actually work. I get errors of this form:
Traceback (most recent call last):
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/request.py", line 378, in __getattribute__
return super(Request, self).__getattribute__(attr)
AttributeError: 'Request' object has no attribute 'body'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/request.py", line 378, in __getattribute__
return super(Request, self).__getattribute__(attr)
AttributeError: 'Request' object has no attribute 'body'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/django/core/handlers/exception.py", line 39, in inner
response = get_response(request)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/django/core/handlers/base.py", line 187, in _get_response
response = self.process_exception_by_middleware(e, request)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/django/core/handlers/base.py", line 185, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/django/views/decorators/csrf.py", line 58, in wrapped_view
return view_func(*args, **kwargs)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/django/views/generic/base.py", line 68, in view
return self.dispatch(request, *args, **kwargs)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/views.py", line 483, in dispatch
response = self.handle_exception(exc)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/views.py", line 443, in handle_exception
self.raise_uncaught_exception(exc)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/views.py", line 480, in dispatch
response = handler(request, *args, **kwargs)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/decorators.py", line 52, in handler
return func(*args, **kwargs)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/project/django-backend/cardamom/worker/views.py", line 196, in dispatch
return view(request)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/django/views/decorators/csrf.py", line 58, in wrapped_view
return view_func(*args, **kwargs)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/django/views/generic/base.py", line 68, in view
return self.dispatch(request, *args, **kwargs)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/views.py", line 483, in dispatch
response = self.handle_exception(exc)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/views.py", line 443, in handle_exception
self.raise_uncaught_exception(exc)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/views.py", line 480, in dispatch
response = handler(request, *args, **kwargs)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/decorators.py", line 52, in handler
return func(*args, **kwargs)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/project/django-backend/cardamom/core/views/mailchimp.py", line 229, in wrapper
return func(*args, **kwargs)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/project/django-backend/cardamom/worker/views.py", line 52, in wrapper
result = f(log_entry, *args, **kwargs)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/project/django-backend/cardamom/worker/views.py", line 106, in match_one
user_id = int(request.data['user_id'])
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/request.py", line 378, in __getattribute__
return super(Request, self).__getattribute__(attr)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/request.py", line 186, in data
self._load_data_and_files()
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/request.py", line 246, in _load_data_and_files
self._data, self._files = self._parse()
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/request.py", line 290, in _parse
stream = self.stream
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/request.py", line 378, in __getattribute__
return super(Request, self).__getattribute__(attr)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/request.py", line 173, in stream
self._load_stream()
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/request.py", line 270, in _load_stream
self._stream = six.BytesIO(self.body)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/request.py", line 382, in __getattribute__
return getattr(self._request, attr)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/rest_framework/request.py", line 382, in __getattribute__
return getattr(self._request, attr)
File "/mnt/d/Users/coriolinus/Documents/Toptal/cardamom/.venv/lib/python3.4/site-packages/django/http/request.py", line 264, in body
raise RawPostDataException("You cannot access body after reading from request's data stream")
django.http.request.RawPostDataException: You cannot access body after reading from request's data stream
Problem restatement
The request object is complicated; generating a new one is implausible. At the same time, we need to modify the data of this one in order to properly pass it along to the next view, so that view only sees the data in its expected format.
How can I accomplish this?
[edit] Passing an un-modified request doesn't work either
I tried editing the above example to remove any modification of the request object, and instead created the following serializer mixin:
class UndispatcherMixin:
"""
Adjust a serializer such that it can accept its normal serialization,
or alternately the payload of a DispatchSerializer.
"""
def is_valid(self, raise_exception=False):
if not hasattr(self, '_validated_data'):
assert hasattr(self, 'initial_data'), (
'Cannot call `.is_valid()` as no `data=` keyword argument was '
'passed when instantiating the serializer instance.'
)
ds = DispatchSerializer(data=self.initial_data)
if ds.is_valid(raise_exception=False):
self.initial_data = ds.validated_data['payload']
return super().is_valid(raise_exception=raise_exception)
This mixin was then added to the relevant serializers used by the downstream views. Interestingly, it failed with the same django.http.RawPostDataException as before.
It's received wisdom all over SO that you can just call your views as normal functions, so long as you pass in a proper request object. This may not actually be true, at least for the case where the view was created by the DRF #api_view decorator.
Still working on a way to actually solve this.

For whatever reason--this may be an error in DRF, but I'm not sure--you can't just call an #api_view function from within another one and pass along the request object. It just doesn't work.
What does work is to factor out the code which does the actual work, and call it separately from the #api_view function and also the dispatch view. That is, something like this:
def perform_action(request, data):
"""
Do something
`request` is included for completeness in case it's necessary,
but the data normally read from `request.data` should be read instead
from the `data` argument.
"""
serializer = ActionSerializer(data=data)
if serializer.is_valid():
... # Whatever your action should be, goes here
#api_view(http_method_names=['POST'])
#permission_classes([AllowAny])
def action(request)
perform_action(request, request.data)
return Response() # 200, no content
#api_view(http_method_names=['POST'])
#permission_classes([AllowAny])
def dispatch(request):
"""
Dispatch a request to a sibling endpoint.
"""
routing_table = {
'action': perform_action, # etc...
}
serializer = DispatchSerializer(data=request.data)
if serializer.is_valid(raise_exception=True):
to = serializer.validated_data['to']
try:
view = routing_table[to]
except KeyError:
raise Http404()
view(request, serializer.validated_data['payload'])
return Response()

RawPostDataException: You cannot access body after reading from request's data stream

I am hosting a site on Google Cloud and I got everything to work beautifully and then all of the sudden I start getting this error..
01:16:22.222
Internal Server Error: /api/v1/auth/login/ (/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/django/core/handlers/exception.py:124)
Traceback (most recent call last):
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/django/core/handlers/exception.py", line 39, in inner
response = get_response(request)
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/django/core/handlers/base.py", line 249, in _legacy_get_response
response = self._get_response(request)
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/django/core/handlers/base.py", line 187, in _get_response
response = self.process_exception_by_middleware(e, request)
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/django/core/handlers/base.py", line 185, in _get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/django/views/decorators/csrf.py", line 58, in wrapped_view
return view_func(*args, **kwargs)
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/django/views/generic/base.py", line 68, in view
return self.dispatch(request, *args, **kwargs)
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/rest_framework/views.py", line 474, in dispatch
response = self.handle_exception(exc)
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/rest_framework/views.py", line 434, in handle_exception
self.raise_uncaught_exception(exc)
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/rest_framework/views.py", line 471, in dispatch
response = handler(request, *args, **kwargs)
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/authentication/views.py", line 42, in post
data = json.loads(request.body)
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/rest_framework/request.py", line 359, in __getattribute__
return getattr(self._request, attr)
File "/base/data/home/apps/s~crs-portal/1.395605052160854207/lib/django/http/request.py", line 263, in body
raise RawPostDataException("You cannot access body after reading from request's data stream")
RawPostDataException: You cannot access body after reading from request's data stream
I have no clue what this means, and endless googling has not solved my case in anyway..
Here's the code that is probably relevant:
views.py
class LoginView(views.APIView):
def post(self, request, format=None):
data = json.loads(request.body)
email = data.get('email', None)
password = data.get('password', None)
account = authenticate(email=email, password=password)
if account is not None:
if account.is_active:
login(request, account)
serialized = AccountSerializer(account)
return Response(serialized.data)
else:
return Response({
'status': 'Unauthorized',
'message': 'This account has been disabled.'
}, status=status.HTTP_401_UNAUTHORIZED)
else:
return Response({
'status': 'Unauthorized',
'message': 'Username/password combination invalid.'
}, status=status.HTTP_401_UNAUTHORIZED)
serializer.py
class AccountSerializer(serializers.ModelSerializer):
password = serializers.CharField(write_only=True, required=False)
confirm_password = serializers.CharField(write_only=True, required=False)
class Meta:
model = Account
fields = ('id', 'email', 'username', 'created_at', 'updated_at', 'full_name', 'password', 'confirm_password')
read_only_fields = ('created_at', 'updated_at',)
def create(self, validated_data):
return Account.objects.create(**validated_data)
def update(self, instance, validated_data):
instance.username = validated_data.get('username', instance.username)
instance.save()
password = validated_data.get('password', None)
confirm_password = validated_data.get('confirm_password', None)
if password and confirm_password and password == confirm_password:
instance.set_password(password)
instance.save()
update_session_auth_hash(self.context.get('request'), instance)
return instance

This is occuring is because you are trying to access the data from body
use -> data = json.loads(request.data)

Use request.data instead of request.body.
request.data does not read the data stream again.

hey thanks for the response but I figured it out! It wasn't working because I found a small bug where I am able to access the login page even though I am already logged in, so the error was caused by trying to login again. I fixed the issue by redirecting to home page if login page is tried to be reached