python - Django viewset has not attribute 'get_extra_actions'

Question

I am working with Django for a first time and I'm trying to build an API and I am following some tutorials and examples and it works right, but I am running the project now in a Raspberry Pi after install all the requirements and the project is failing with the following error:

    Performing system checks...

Unhandled exception in thread started by <function check_errors.<locals>.wrapper at 0xb547adb0>
Traceback (most recent call last):
  File "/home/pi/.local/lib/python3.5/site-packages/django/utils/autoreload.py", line 225, in wrapper
    fn(*args, **kwargs)
  File "/home/pi/.local/lib/python3.5/site-packages/django/core/management/commands/runserver.py", line 120, in inner_run
    self.check(display_num_errors=True)
  File "/home/pi/.local/lib/python3.5/site-packages/django/core/management/base.py", line 364, in check
    include_deployment_checks=include_deployment_checks,
  File "/home/pi/.local/lib/python3.5/site-packages/django/core/management/base.py", line 351, in _run_checks
    return checks.run_checks(**kwargs)
  File "/home/pi/.local/lib/python3.5/site-packages/django/core/checks/registry.py", line 73, in run_checks
    new_errors = check(app_configs=app_configs)
  File "/home/pi/.local/lib/python3.5/site-packages/django/core/checks/urls.py", line 13, in check_url_config
    return check_resolver(resolver)
  File "/home/pi/.local/lib/python3.5/site-packages/django/core/checks/urls.py", line 23, in check_resolver
    return check_method()
  File "/home/pi/.local/lib/python3.5/site-packages/django/urls/resolvers.py", line 397, in check
    for pattern in self.url_patterns:
  File "/home/pi/.local/lib/python3.5/site-packages/django/utils/functional.py", line 36, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/home/pi/.local/lib/python3.5/site-packages/django/urls/resolvers.py", line 536, in url_patterns
    patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
  File "/home/pi/.local/lib/python3.5/site-packages/django/utils/functional.py", line 36, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/home/pi/.local/lib/python3.5/site-packages/django/urls/resolvers.py", line 529, in urlconf_module
    return import_module(self.urlconf_name)
  File "/usr/lib/python3.5/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 986, in _gcd_import
  File "<frozen importlib._bootstrap>", line 969, in _find_and_load
  File "<frozen importlib._bootstrap>", line 958, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 673, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 673, in exec_module
  File "<frozen importlib._bootstrap>", line 222, in _call_with_frames_removed
  File "/home/pi/Projects/openvpn-monitor/openvpnmonitor/urls.py", line 24, in <module>
    url(r'^api/', include('openvpnmonitor.api.urls')),
  File "/home/pi/.local/lib/python3.5/site-packages/django/urls/conf.py", line 34, in include
    urlconf_module = import_module(urlconf_module)
  File "/usr/lib/python3.5/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 986, in _gcd_import
  File "<frozen importlib._bootstrap>", line 969, in _find_and_load
  File "<frozen importlib._bootstrap>", line 958, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 673, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 673, in exec_module
  File "<frozen importlib._bootstrap>", line 222, in _call_with_frames_removed
  File "/home/pi/Projects/openvpn-monitor/openvpnmonitor/api/urls.py", line 16, in <module>
    urlpatterns += router.urls
  File "/home/pi/.local/lib/python3.5/site-packages/rest_framework/routers.py", line 101, in urls
    self._urls = self.get_urls()
  File "/home/pi/.local/lib/python3.5/site-packages/rest_framework/routers.py", line 363, in get_urls
    urls = super(DefaultRouter, self).get_urls()
  File "/home/pi/.local/lib/python3.5/site-packages/rest_framework/routers.py", line 261, in get_urls
    routes = self.get_routes(viewset)
  File "/home/pi/.local/lib/python3.5/site-packages/rest_framework/routers.py", line 176, in get_routes
    extra_actions = viewset.get_extra_actions()
AttributeError: type object 'SessionViewSet' has no attribute 'get_extra_actions'

My views.py has the following code:

from django.shortcuts import render

from rest_framework import viewsets
from .models import Session
from .serializers import SessionSerializer

from rest_framework.views import APIView, Response


class SessionViewSet(APIView):
    queryset = Session.objects.all()
    serializer_class = SessionSerializer

    def get(self, request, format=None):
        return Response("test")

I really don't know why is working on my laptop but it is not working on my Raspberry Pi.

Has this happened to someone or anyone knows why is happening this?

Thank you so much!

Edit:

Here is my urls.py

from django.conf.urls import url
from rest_framework import routers
from openvpnmonitor.api.views import SessionViewSet

router = routers.DefaultRouter()
router.register(r'sessions', SessionViewSet)

urlpatterns = [
    url(r'sessions', SessionViewSet.as_view()),
    url(r'^docs/', schema_view),
]

urlpatterns += router.urls

Answer 1

You've called it a viewset, but that doesn't make it one; you inherit from APIView which is a standalone generic view, not a viewset.

A viewset needs to inherit from viewsets.ViewSet.