Django 2 - How to register a user using email confirmation and CBVs?

Question

This question specifically aims for a Django 2.0 answer as the registration module isn't available (yet) for it.

More, this might seem to broad, but I often found myself in situations where I can't use any 3rd party module because ... oh well..policies. I'm sure many did. And I know that looking and putting together information taken from here or django docs was a headache.

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Workflow:

Let's suppose we need the following flow:

1. The user goes to the sign-up page and fills in the following fields: first_name, last_name and email (the email will be used as the username).
2. The user submits the form and receives a confirmation email with an URL containing a unique token.
3. When the user clicks on the received link, he's redirected to a page where he'll set his password. When done, he's logged in to the dashboard page.

Extra-info: The user will later log in by using his email (which is actually his username) and password.

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Specific question:

• How will the models/views (using CBVs)/forms/urls look like?

Answer 1

The User Model

First, you will need to create a custom User model and a custom UserManager to remove the username field and use email instead.

In models.py the UserManager should look like this:

from django.contrib.auth.models import BaseUserManager


class MyUserManager(BaseUserManager):
    """
    A custom user manager to deal with emails as unique identifiers for auth
    instead of usernames. The default that's used is "UserManager"
    """
    def _create_user(self, email, password, **extra_fields):
        """
        Creates and saves a User with the given email and password.
        """
        if not email:
            raise ValueError('The Email must be set')
        email = self.normalize_email(email)
        user = self.model(email=email, **extra_fields)
        user.set_password(password)
        user.save()
        return user

    def create_superuser(self, email, password, **extra_fields):
        extra_fields.setdefault('is_staff', True)
        extra_fields.setdefault('is_superuser', True)
        extra_fields.setdefault('is_active', True)

        if extra_fields.get('is_staff') is not True:
            raise ValueError('Superuser must have is_staff=True.')
        if extra_fields.get('is_superuser') is not True:
            raise ValueError('Superuser must have is_superuser=True.')
        return self._create_user(email, password, **extra_fields)

And the User model:

from django.db import models
from django.contrib.auth.models import AbstractBaseUser
from django.contrib.auth.models import PermissionsMixin
from django.utils.translation import ugettext_lazy as _


class User(AbstractBaseUser, PermissionsMixin):
    email = models.EmailField(unique=True, null=True)
    is_staff = models.BooleanField(
        _('staff status'),
        default=False,
        help_text=_('Designates whether the user can log into this site.'),
    )
    is_active = models.BooleanField(
        _('active'),
        default=True,
        help_text=_(
            'Designates whether this user should be treated as active. '
            'Unselect this instead of deleting accounts.'
        ),
    )
    USERNAME_FIELD = 'email'
    objects = MyUserManager()

    def __str__(self):
        return self.email

    def get_full_name(self):
        return self.email

    def get_short_name(self):
        return self.email

And finally in settings.py:

AUTH_USER_MODEL = 'your_app_name.User'

---

The Token Generator

Second part is to create a token generator for the email confirmation url. We can inherit the built-in PasswordResetTokenGenerator to make it easier.

Create tokens.py:

from django.contrib.auth.tokens import PasswordResetTokenGenerator
from django.utils import six

class TokenGenerator(PasswordResetTokenGenerator):
    def _make_hash_value(self, user, timestamp):
        return (
            six.text_type(user.pk) + six.text_type(timestamp) +
            six.text_type(user.is_active)
        )

account_activation_token = TokenGenerator()

---

The Signup Form

Then you should create a registration form to use in our views. Best way is to inherit the built-in Django's UserCreationForm and to remove the username and password fields from it and then add an email field. forms.py:

from django import forms
from django.contrib.auth.forms import UserCreationForm
from django.contrib.auth.models import User

class SignupForm(UserCreationForm):
    email = forms.EmailField(max_length=200, help_text='Required')

    class Meta:
        model = User
        fields = ('email', 'first_name', 'last_name')

---

The Signup View

In the sign up you should make the user inactive user.is_active = False with no password set_unusable_password() until the user complete the activation. Also, we are going to construct an activation URL and email it to the user after completing the registration.

in views.py:

from django.views import View
from django.http import HttpResponse
from django.shortcuts import render
from .forms import SignupForm
from django.contrib.sites.shortcuts import get_current_site
from django.utils.encoding import force_bytes
from django.utils.http import urlsafe_base64_encode
from .tokens import account_activation_token
from django.core.mail import EmailMessage


class Signup(View):
    def get(self, request):
        form = SignupForm()
        return render(request, 'signup.html', {'form': form})

    def post(self, request):
        form = SignupForm(request.POST)
        if form.is_valid():
            # Create an inactive user with no password:
            user = form.save(commit=False)
            user.is_active = False
            user.set_unusable_password()
            user.save()

            # Send an email to the user with the token:
            mail_subject = 'Activate your account.'
            current_site = get_current_site(request)
            uid = urlsafe_base64_encode(force_bytes(user.pk))
            token = account_activation_token.make_token(user)
            activation_link = "{0}/?uid={1}&token{2}".format(current_site, uid, token)
            message = "Hello {0},\n {1}".format(user.username, activation_link)
            to_email = form.cleaned_data.get('email')
            email = EmailMessage(mail_subject, message, to=[to_email])
            email.send()
            return HttpResponse('Please confirm your email address to complete the registration')

And of course, don't forget to create a template for you signup view.

---

The Activation View

Then you should create a view for the user to activate his account using the URL we created in the sign up view. We will also use the built-in Django's SetPasswordForm to allow users to set their passwords.

In views.py:

from django.contrib.auth import get_user_model, login, update_session_auth_hash
from django.contrib.auth.forms import PasswordChangeForm
from django.utils.encoding import force_bytes, force_text
from django.utils.http import urlsafe_base64_encode, urlsafe_base64_decode
from .tokens import account_activation_token

User = get_user_model()

class Activate(View):
    def get(self, request, uidb64, token):
        try:
            uid = force_text(urlsafe_base64_decode(uidb64))
            user = User.objects.get(pk=uid)
        except(TypeError, ValueError, OverflowError, User.DoesNotExist):
            user = None
        if user is not None and account_activation_token.check_token(user, token):
            # activate user and login:
            user.is_active = True
            user.save()
            login(request, user)
            
            form = PasswordChangeForm(request.user)
            return render(request, 'activation.html', {'form': form})
            
        else:
            return HttpResponse('Activation link is invalid!')
            
    def post(self, request):
        form = PasswordChangeForm(request.user, request.POST)
        if form.is_valid():
            user = form.save()
            update_session_auth_hash(request, user) # Important, to update the session with the new password
            return HttpResponse('Password changed successfully')

Again, don't forget to create a template for your activation view.

---

The URLs

Finally, in urls.py:

from . import views
from django.urls import path

urlpatterns = [
    ...
    path('signup/', views.signup.as_view(), name='signup'),
    path('activate/<str:uid>/<str:token>', views.activate.as_view(), name='activate'),
]

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P.S. Honestly, I didn't get a chance to test all this parts together yet but don't hesitate to ask if any problem happened.