Django - Login with Email

Question

I want django to authenticate users via email, not via usernames. One way can be providing email value as username value, but I dont want that. Reason being, I've a url /profile/<username>/, hence I cannot have a url /profile/[email protected]/.

Another reason being that all emails are unique, but it happen sometimes that the username is already being taken. Hence I'm auto-creating the username as fullName_ID.

How can I just change let Django authenticate with email?

This is how I create a user.

username = `abcd28`
user_email = `[email protected]`
user = User.objects.create_user(username, user_email, user_pass)

This is how I login.

email = request.POST['email']
password = request.POST['password']
username = User.objects.get(email=email.lower()).username
user = authenticate(username=username, password=password)
login(request, user)

Is there any other of of login apart from getting the username first?

Answer 1

You should write a custom authentication backend. Something like this will work:

from django.contrib.auth import get_user_model
from django.contrib.auth.backends import ModelBackend

class EmailBackend(ModelBackend):
    def authenticate(self, request, username=None, password=None, **kwargs):
        UserModel = get_user_model()
        try:
            user = UserModel.objects.get(email=username)
        except UserModel.DoesNotExist:
            return None
        else:
            if user.check_password(password):
                return user
        return None

Then, set that backend as your auth backend in your settings:

AUTHENTICATION_BACKENDS = ['path.to.auth.module.EmailBackend']

Updated. Inherit from ModelBackend as it implements methods like get_user() already.

See docs here: https://docs.djangoproject.com/en/3.0/topics/auth/customizing/#writing-an-authentication-backend

Answer 2

If you’re starting a new project, django highly recommended you to set up a custom user model. (see https://docs.djangoproject.com/en/dev/topics/auth/customizing/#using-a-custom-user-model-when-starting-a-project)

and if you did it, add three lines to your user model:

class MyUser(AbstractUser):
    USERNAME_FIELD = 'email'
    email = models.EmailField(_('email address'), unique=True) # changes email to unique and blank to false
    REQUIRED_FIELDS = [] # removes email from REQUIRED_FIELDS

Then authenticate(email=email, password=password) works, while authenticate(username=username, password=password) stops working.

Answer 3

Email authentication for Django 3.x

For using email/username and password for authentication instead of the default username and password authentication, we need to override two methods of ModelBackend class: authenticate() and get_user():

The get_user method takes a user_id – which could be a username, database ID or whatever, but has to be unique to your user object – and returns a user object or None. If you have not kept email as a unique key, you will have to take care of multiple result returned for the query_set. In the below code, this has been taken care of by returning the first user from the returned list.

from django.contrib.auth.backends import ModelBackend, UserModel
from django.db.models import Q

class EmailBackend(ModelBackend):
    def authenticate(self, request, username=None, password=None, **kwargs):
        try: #to allow authentication through phone number or any other field, modify the below statement
            user = UserModel.objects.get(Q(username__iexact=username) | Q(email__iexact=username))
        except UserModel.DoesNotExist:
            UserModel().set_password(password)
        except MultipleObjectsReturned:
            return User.objects.filter(email=username).order_by('id').first()
        else:
            if user.check_password(password) and self.user_can_authenticate(user):
                return user

    def get_user(self, user_id):
        try:
            user = UserModel.objects.get(pk=user_id)
        except UserModel.DoesNotExist:
            return None

        return user if self.user_can_authenticate(user) else None

By default, AUTHENTICATION_BACKENDS is set to:

['django.contrib.auth.backends.ModelBackend']

In settings.py file, add following at the bottom to override the default:

AUTHENTICATION_BACKENDS = ('appname.filename.EmailBackend',)

Answer 4

I had a similar requirement where either username/email should work for the username field.In case someone is looking for the authentication backend way of doing this,check out the following working code.You can change the queryset if you desire only the email.

from django.contrib.auth import get_user_model  # gets the user_model django  default or your own custom
from django.contrib.auth.backends import ModelBackend
from django.db.models import Q


# Class to permit the athentication using email or username
class CustomBackend(ModelBackend):  # requires to define two functions authenticate and get_user

    def authenticate(self, username=None, password=None, **kwargs):
        UserModel = get_user_model()

        try:
            # below line gives query set,you can change the queryset as per your requirement
            user = UserModel.objects.filter(
                Q(username__iexact=username) |
                Q(email__iexact=username)
            ).distinct()

        except UserModel.DoesNotExist:
            return None

        if user.exists():
            ''' get the user object from the underlying query set,
            there will only be one object since username and email
            should be unique fields in your models.'''
            user_obj = user.first()
            if user_obj.check_password(password):
                return user_obj
            return None
        else:
            return None

    def get_user(self, user_id):
        UserModel = get_user_model()
        try:
            return UserModel.objects.get(pk=user_id)
        except UserModel.DoesNotExist:
            return None

Also add AUTHENTICATION_BACKENDS = ( 'path.to.CustomBackend', ) in settings.py

Answer 5

Django 2.x

As mentioned by Ganesh above for django 2.x the authenticate method now requires a request param.

# backends.py
from django.contrib.auth import backends, get_user_model
from django.db.models import Q
UserModel = get_user_model()


class ModelBackend(backends.ModelBackend):

    def authenticate(self, request, username=None, password=None, **kwargs):
        if username is None:
            username = kwargs.get(UserModel.USERNAME_FIELD)
        try:
            # user = UserModel._default_manager.get_by_natural_key(username)
            # You can customise what the given username is checked against, here I compare to both username and email fields of the User model
            user = UserModel.objects.get(Q(username__iexact=username) | Q(email__iexact=username))
        except UserModel.DoesNotExist:
            # Run the default password hasher once to reduce the timing
            # difference between an existing and a nonexistent user (#20760).
            UserModel().set_password(password)
        else:
            if user.check_password(password) and self.user_can_authenticate(user):
                return user
        return super().authenticate(request, username, password, **kwargs)

add your backend to your project settings

# settings.py
AUTHENTICATION_BACKENDS = ['path.to.ModelBackend']

Your custom User model will need to make emails unique for active and validated users you can do this simply with something like this:

from django.contrib.auth.models import AbstractUser


class User(AbstractUser):
    objects = UserManager()
    email = models.EmailField(_('email address'), unique=True)

    class Meta:
        verbose_name = _('user')
        verbose_name_plural = _('users')
        db_table = 'auth_user'
        swappable = 'AUTH_USER_MODEL'

But to prevent someone blocking someone else from using their email you should add email validation instead and have your registration and login process take into account that emails may not be unique (and probably prevent new users using an existing and validated email address).

Answer 6

Email and Username Authentication for Django 2.X

Having in mind that this is a common question, here's a custom implementation mimicking the Django source code but that authenticates the user with either username or email, case-insensitively, keeping the timing attack protection and not authenticating inactive users.

from django.contrib.auth.backends import ModelBackend, UserModel
from django.db.models import Q

class CustomBackend(ModelBackend):
    def authenticate(self, request, username=None, password=None, **kwargs):
        try:
            user = UserModel.objects.get(Q(username__iexact=username) | Q(email__iexact=username))
        except UserModel.DoesNotExist:
            UserModel().set_password(password)
        else:
            if user.check_password(password) and self.user_can_authenticate(user):
                return user

    def get_user(self, user_id):
        try:
            user = UserModel.objects.get(pk=user_id)
        except UserModel.DoesNotExist:
            return None

        return user if self.user_can_authenticate(user) else None

Always remember to add it your settings.py the correct Authentication Backend.

Answer 7

You should customize ModelBackend class. My simple code:

from django.contrib.auth.backends import ModelBackend
from django.contrib.auth import get_user_model

class YourBackend(ModelBackend):

  def authenticate(self, username=None, password=None, **kwargs):
    UserModel = get_user_model()
    if username is None:
        username = kwargs.get(UserModel.USERNAME_FIELD)
    try:
        if '@' in username:
            UserModel.USERNAME_FIELD = 'email'
        else:
            UserModel.USERNAME_FIELD = 'username'

        user = UserModel._default_manager.get_by_natural_key(username)
    except UserModel.DoesNotExist:
        UserModel().set_password(password)
    else:
        if user.check_password(password) and self.user_can_authenticate(user):
            return user

And in settings.py file, add:

AUTHENTICATION_BACKENDS = ['path.to.class.YourBackend']

Answer 8

Authentication with Email and Username For Django 2.x

from django.contrib.auth import get_user_model
from django.contrib.auth.backends import ModelBackend
from django.db.models import Q

class EmailorUsernameModelBackend(ModelBackend):
    def authenticate(self, request, username=None, password=None, **kwargs):
        UserModel = get_user_model()
        try:
            user = UserModel.objects.get(Q(username__iexact=username) | Q(email__iexact=username))
        except UserModel.DoesNotExist:
            return None
        else:
            if user.check_password(password):
                return user
        return None

In settings.py, add following line,

AUTHENTICATION_BACKENDS = ['appname.filename.EmailorUsernameModelBackend']

Answer 9

from django.contrib.auth.models import User

from django.db import Q

class EmailAuthenticate(object):

    def authenticate(self, username=None, password=None, **kwargs):
        try:
            user = User.objects.get(Q(email=username) | Q(username=username))
        except User.DoesNotExist:
            return None
        except MultipleObjectsReturned:
            return User.objects.filter(email=username).order_by('id').first()

        if user.check_password(password):
            return user
        return None

    def get_user(self,user_id):
        try:
            return User.objects.get(pk=user_id)
        except User.DoesNotExist:
            return None

And then in settings.py:

AUTHENTICATION_BACKENDS = (
  'articles.backends.EmailAuthenticate',
)

where articles is my django-app, backends.py is the python file inside my app and EmailAuthenticate is the authentication backend class inside my backends.py file

Answer 10

I have created a helper for that: function authenticate_user(email, password).

from django.contrib.auth.models import User


def authenticate_user(email, password):
    try:
        user = User.objects.get(email=email)
    except User.DoesNotExist:
        return None
    else:
        if user.check_password(password):
            return user

    return None

class LoginView(View):
    template_name = 'myapp/login.html'

    def get(self, request):
        return render(request, self.template_name)

    def post(self, request):
        email = request.POST['email']
        password = request.POST['password']
        user = authenticate_user(email, password)
        context = {}

        if user is not None:
            if user.is_active:
                login(request, user)

                return redirect(self.request.GET.get('next', '/'))
            else:
                context['error_message'] = "user is not active"
        else:
            context['error_message'] = "email or password not correct"

        return render(request, self.template_name, context)

Answer 11

For Django 2

username = get_object_or_404(User, email=data["email"]).username
        user = authenticate(
            request, 
            username = username, 
            password = data["password"]
        )
        login(request, user)

Answer 12

Authentication with Email For Django 2.x

def admin_login(request):
if request.method == "POST":
    email = request.POST.get('email', None)
    password = request.POST.get('password', None)
    try:
        get_user_name = CustomUser.objects.get(email=email)
        user_logged_in =authenticate(username=get_user_name,password=password)
        if user_logged_in is not None:
            login(request, user_logged_in)
            messages.success(request, f"WelcomeBack{user_logged_in.username}")
            return HttpResponseRedirect(reverse('backend'))
        else:
            messages.error(request, 'Invalid Credentials')
            return HttpResponseRedirect(reverse('admin_login'))
    except:
        messages.warning(request, 'Wrong Email')
        return HttpResponseRedirect(reverse('admin_login'))

else:
    if request.user.is_authenticated:
        return HttpResponseRedirect(reverse('backend'))
    return render(request, 'login_panel/login.html')

Answer 13

If You created Custom database, from there if you want to validate your email id and password.

1. Fetch the Email id and Password with models.objects.value_list('db_columnname').filter(db_emailname=textbox email)

2.assign in list fetched object_query_list

3.Convert List to String

Ex :

1. Take the Html Email_id and Password Values in Views.py

   u_email = request.POST.get('uemail')

   u_pass = request.POST.get('upass')

2. Fetch the Email id and password from the database

   Email = B_Reg.objects.values_list('B_Email',flat=True).filter(B_Email=u_email)

   Password = B_Reg.objects.values_list('Password',flat=True).filter(B_Email=u_email)

3. Take the Email id and password values in the list from the Query value set

   Email_Value = Email[0]

   Password_Value=Password[0]

4. Convert list to String

   string_email = ''.join(map(str, Email_Value))

   string_password = ''.join(map(str, Password_Value))

Finally your Login Condition

if (string_email==u_email and string_password ==u_pass)

Answer 14

Pretty simple. There is no need for any additional classes.

When you create and update a user with an email, just set the username field with the email.

That way when you authenticate the username field will be the same value of the email.

The code:

# Create
User.objects.create_user(username=post_data['email'] etc...)

# Update
user.username = post_data['email']
user.save()

# When you authenticate
user = authenticate(username=post_data['email'], password=password)

Answer 15

It seems that the method of doing this has been updated with Django 3.0.

A working method for me has been:

authentication.py # <-- I placed this in an app (did not work in the project folder alongside settings.py

from django.contrib.auth import get_user_model
from django.contrib.auth.backends import BaseBackend
from django.contrib.auth.hashers import check_password
from django.contrib.auth.models import User

class EmailBackend(BaseBackend):
    def authenticate(self, request, username=None, password=None, **kwargs):
        UserModel = get_user_model()
        try:
            user = UserModel.objects.get(email=username)
        except UserModel.DoesNotExist:
            return None
        else:
            if user.check_password(password):
                return user
        return None

    def get_user(self, user_id):
        UserModel = get_user_model()
        try:
            return UserModel.objects.get(pk=user_id)
        except UserModel.DoesNotExist:
            return None

Then added this to the settings.py file

AUTHENTICATION_BACKENDS = (
    'appname.authentication.EmailBackend',
)

Answer 16

The default user model inherits/ Extends an Abstract class. The framework should be lenient to a certain amount of changes or alterations.

A simpler hack is to do the following: This is in a virtual environment

1. Go to your django installation location and find the Lib folder
2. navigate to django/contrib/auth/
3. find and open the models.py file. Find the AbstractUser class line 315

LINE 336 on the email attribute add unique and set it to true

email = models.EmailField(_('email address'), blank=True,unique=True)

USERNAME_FIELD = 'email'
REQUIRED_FIELDS = ['username']

5. Done, makemigrations & migrate

Do this at you own risk,