CSRF令牌丢失或不正确，404

Question

This is a widely asked question, but most of them have a different scenario, and I believe mine too.

Below are my project details

apps.ulrs.py:

urlpatterns = [
  url(r'^index/$', views.IndexView, name='index'),
  url(r'^signup/$', views.signupview, name='sign_up'),    
]

models.py:

from django.db import models
from django.core.urlresolvers import reverse
#from django.core.urlresolvers import reverse
from django.contrib.auth.models import User
from django.db.models.signals import post_save
from django.dispatch import receiver

class Registration(models.Model):
    user = models.OneToOneField(User, on_delete=models.CASCADE)
    username = models.CharField(max_length = 250)
    password = models.CharField(max_length = 250)
    email = models.CharField(max_length = 250)

@receiver(post_save, sender=User)
def update_user_profile(sender, instance, created, **kwargs):
    if created:
        Registration.objects.create(user=instance)
    instance.registration.save()

views.py:

from django.shortcuts import render, redirect
from django.contrib.auth import authenticate, login
from django.contrib.auth.forms import UserCreationForm
from .forms import SignUpForm
#from django.corecontext_processors import csrf
from django.template import RequestContext
from django.shortcuts import render_to_response
from django.views import generic


class IndexView(generic.View):
    templet_name = 'user_info/index.html'


def signupview(request):
    if request.method == 'POST':
        form = SignUpForm(request.POST)
        if form.is_valid():
            form.save()
            username = form.cleaned_data.get('username')
            raw_password = form.cleaned_data.get('password')
            user = authenticate(username=username, password=raw_password)
            login(request, user)
            return redirect('registration_form.html')

    else:
        form = SignUpForm()
    #return render(request,'user_info/registration_form.html',  {'form': form})
    return render_to_response('user_info/registration_form.html',  {'form': form,  }, context_instance = RequestContext(request))

I doing some research I came to know that we need to import "csrf" in my views.py , so I tried below:

#from django.corecontext_processors import csrf

But as per my understanding goes, it was deprecated since django 1.8. Please correct me if I am wrong. I am using python 3.6, and django 1.11. So, what would be the library I am supposed to import for 'csrf'?

I do have {% csrf_token %} inside my html file inside tag:

{% block title %}register{% endblock %}

{% block body %}


{% block content %}
  <h2>Sign up</h2>
  <form method="post">
    {% csrf_token %}
    {% for field in form %}
      <p>
        {{ field.label_tag }}<br>
        {{ field }}
        {% if field.help_text %}
          <small style="color: grey">{{ field.help_text }}</small>
        {% endif %}
        {% for error in field.errors %}
          <p style="color: red">{{ error }}</p>
        {% endfor %}
      </p>
    {% endfor %}
    <button type="submit">Sign up</button>
  </form>
{% endblock %}
{% endblock %}

the exact error that I get is:

Forbidden (403)
CSRF verification failed. Request aborted.
Help
Reason given for failure:
    CSRF token missing or incorrect.

Answer 1

Don't use render_to_response , it's obsolete. Uncomment the line that uses render and use that instead.

return render(request,'user_info/registration_form.html', {'form': form})

When you use render , there is no need to use RequestContext or the csrf context processor in your view.