MultiValueDictKeyError in Django when use POST

Question

I am new to Django rest framework and was asked to write the token authentication part of our project. One thing to note is, as I would use not use the default admin site in future, I write login, logout, signup functions, and test the functionality by POSTMAN. What I want to do now is to let new user signup, login and logout. When a user log in, I issue him/her a token. Everything just perform in the easiest way.

But I still can't work it out. I searched all the related questions but still cannot solve my problem. If someone know how to do, please help me! Following is the details.

When I am using GET, everything works fine. But when I am using POST, I get MultiValueDictKeyError. I don't know why.

View.py

    from rest_framework.response import Response
    from django.contrib.auth import authenticate
    from rest_framework.authtoken.models import Token
    from rest_framework import status
    from django.contrib.auth.models import User
    from rest_framework.authentication import TokenAuthentication
    from rest_framework.permissions import IsAuthenticated
    from django.contrib.auth.signals import user_logged_in, user_logged_out
    from rest_framework.decorators import api_view, authentication_classes, permission_classes
    from django.views.decorators.csrf import csrf_exempt, requires_csrf_token
    @csrf_exempt
    @requires_csrf_token
    @api_view(['POST'])
    def create_user_view(request):
        if request.method == 'POST':
            username = request.POST['username']
            email = request.POST['email']
            password = request.POST['password']
            user = User.objects.create_user(username=username, email=email,     password=password)
            user.save()
            return Response({'detail': "Create user"})


    @csrf_exempt
    def login_view(request):
         if request.method == 'POST':
            username = request.POST['username']
            password = request.POST['password']
            user = authenticate(username=username, password=password)
         if user is not None:
            user_logged_in.send(sender=user.__class__, request=request, user=user)
            token = Token.objects.get_or_create(user=user)
            return Response({
                           'detail': 'POST answer', 'token': token[0].key,
                           })
        else:
            return Response({'detail': "The username or password were incorrect.",
           status: status.HTTP_404_NOT_FOUND})

    @csrf_exempt
    def logout_view(request):
        if request.method == 'POST':
            user = getattr(request, 'user', None)
            if hasattr(user, 'is_authenticated') and not user.is_authenticated():
                user = None
                user_logged_out.send(sender=user.__class__, request=request, user=user)
            if hasattr(request, 'user'):
                 from django.contrib.auth.models import AnonymousUser

                 request.user = AnonymousUser()
           return Response({'detail': "You have logged out successfully."})

Test_app/Urls.py

    from django.conf.urls import patterns, url
    from rest_framework.urlpatterns import format_suffix_patterns
    from test_app import views
    urlpatterns = patterns('test_app.views',
                           url(r'^signup', views.create_user_view),
                           url(r'^login', views.login_view),
                           url(r'^logout', views.logout_view),
                           url(r'^auth', views.AuthView),
                           )
    urlpatterns = format_suffix_patterns(urlpatterns)

Models.py(Yes, I only put two lines in the file)

    from django.contrib.auth.models import User
    from django.db import models

I also modified settings.py as tutorial said.

The problem now is:

Request Method: POST
Request URL:    http://127.0.0.1:8000/signup?username=haha&[email protected]&password=okok
Django Version: 1.8.2
Exception Type: MultiValueDictKeyError
Exception Value:    
"'username'"
Exception Location: /Users/wyq/PycharmProjects/env/lib/python2.7/site-packages/django/utils/datastructures.py in __getitem__, line 322

Can anyone help? Thank you very much!

Answer 1

MultiValueDictKeyError occurs in a QueryDict when the key you are trying to access is not present in the QueryDict. Your request method says POST but the url scheme suggests that the parameters you are passing will go the request.GET dict.

You need to submit the parameters via a form or something for them to be accessible in the request.POST QueryDict