django-rest-passwordreset 1.6.0

An extension of django rest framework, providing a configurable password reset strategy

Django Rest Password Reset

This python package provides a simple password reset strategy for django rest framework, where users can request password reset tokens via their registered e-mail address.

The main idea behind this package is to not make any assumptions about how the token is delivered to the end-user (e-mail, text-message, etc...). Instead, this package provides a signal that can be reacted on (e.g., by sending an e-mail or a text message).

This package basically provides two REST endpoints:

• Request a token
• Verify (confirm) a token (and change the password)

Quickstart

1. Install the package from pypi using pip:

pip install django-rest-passwordreset

2. Add django_rest_passwordreset to your INSTALLED_APPS (after rest_framework) within your Django settings file:

INSTALLED_APPS = (
    ...
    'django.contrib.auth',
    ...
    'rest_framework',
    ...
    'django_rest_passwordreset',
    ...
)

3. This package stores tokens in a separate database table (see django_rest_passwordreset/models.py). Therefore, you have to run django migrations:

python manage.py migrate

4. This package provides three endpoints, which can be included by including django_rest_passwordreset.urls in your urls.py as follows:

from django.urls import path, include

urlpatterns = [
    ...
    path(r'^api/password_reset/', include('django_rest_passwordreset.urls', namespace='password_reset')),
    ...
]

Note: You can adapt the URL to your needs.

Endpoints

The following endpoints are provided:

• POST ${API_URL}/ - request a reset password token by using the email parameter
• POST ${API_URL}/confirm/ - using a valid token, the users password is set to the provided password
• POST ${API_URL}/validate_token/ - will return a 200 if a given token is valid

where ${API_URL}/ is the url specified in your urls.py (e.g., api/password_reset/ as in the example above)

Invalid, expired, or unusable tokens return the same generic HTTP 404 response on the confirm and validate_token endpoints. Expired tokens are deleted when presented, but the response intentionally does not say whether the token was missing, expired, or unusable.

Signals

• reset_password_token_created(sender, instance, reset_password_token) Fired when a reset password token is generated
• pre_password_reset(sender, user, reset_password_token) - fired just before a password is being reset
• post_password_reset(sender, user, reset_password_token) - fired after a password has been reset

Example for sending an e-mail

1. Create two new django templates: email/user_reset_password.html and email/user_reset_password.txt. Those templates will contain the e-mail message sent to the user, aswell as the password reset link (or token). Within the templates, you can access the following context variables: current_user, username, email, reset_password_url. Feel free to adapt this to your needs.

2. Add the following code, which contains a Django Signal Receiver (@receiver(...)), to your application. Take care where to put this code, as it needs to be executed by the python interpreter (see the section The reset_password_token_created signal is not fired below, aswell as this part of the django documentation and How to Create Django Signals Tutorial for more information).

from django.core.mail import EmailMultiAlternatives
from django.dispatch import receiver
from django.template.loader import render_to_string
from django.urls import reverse

from django_rest_passwordreset.signals import reset_password_token_created


@receiver(reset_password_token_created)
def password_reset_token_created(sender, instance, reset_password_token, *args, **kwargs):
    """
    Handles password reset tokens
    When a token is created, an e-mail needs to be sent to the user
    :param sender: View Class that sent the signal
    :param instance: View Instance that sent the signal
    :param reset_password_token: Token Model Object
    :param args:
    :param kwargs:
    :return:
    """
    # send an e-mail to the user
    context = {
        'current_user': reset_password_token.user,
        'username': reset_password_token.user.username,
        'email': reset_password_token.user.email,
        'reset_password_url': "{}?token={}".format(
            instance.request.build_absolute_uri(reverse('password_reset:reset-password-confirm')),
            reset_password_token.key)
    }

    # render email text
    email_html_message = render_to_string('email/user_reset_password.html', context)
    email_plaintext_message = render_to_string('email/user_reset_password.txt', context)

    msg = EmailMultiAlternatives(
        # title:
        "Password Reset for {title}".format(title="Some website title"),
        # message:
        email_plaintext_message,
        # from:
        "[e-mail]",
        # to:
        [reset_password_token.user.email]
    )
    msg.attach_alternative(email_html_message, "text/html")
    msg.send()

3. You should now be able to use the endpoints to request a password reset token via your e-mail address. If you want to test this locally, I recommend using some kind of fake mailserver (such as maildump).

Configuration / Settings

The following settings can be set in Django settings.py file:

• DJANGO_REST_MULTITOKENAUTH_RESET_TOKEN_EXPIRY_TIME - time in hours about how long the token is active (Default: 24)

  Please note: expired tokens are automatically cleared based on this setting in every call of ResetPasswordRequestToken.post. The token-validation and password-confirm endpoints do not run this bulk cleanup (an expired token presented there is rejected and deleted individually by the serializer); running a full-table cleanup on those high-frequency, attack-exposed endpoints would be a DoS amplification vector. For reliable DB hygiene without relying on reset requests coming in, schedule the management command below.

Token cleanup (expired-token removal)

The package ships a management command to bulk-remove expired tokens:

python manage.py clearresetpasswodtokens

It deletes every ResetPasswordToken with created_at older than DJANGO_REST_MULTITOKENAUTH_RESET_TOKEN_EXPIRY_TIME hours. Schedule it (cron, systemd timer, Celery beat, Django-Q, or django-future-tasks) for periodic DB hygiene — for example once an hour or once a day:

# crontab example: clear expired reset tokens every hour at :05
5 * * * * /path/to/venv/bin/python /path/to/manage.py clearresetpasswodtokens

This is the recommended way to keep the token table small. The cleanup query filters on indexed created_at values, avoiding an unindexed scan before deleting matching rows.

Individual expired tokens are also removed on use: when an expired token is submitted to the validate or confirm endpoint, the serializer deletes that single token and rejects the request (HTTP 404). The bulk command above is therefore about reclaiming rows for tokens that are never presented again, not about security enforcement.

• DJANGO_REST_PASSWORDRESET_NO_INFORMATION_LEAKAGE - when True (the default in the next release), a 200 OK is always returned on POST ${API_URL}/reset_password/, even if the user does not exist in the database, so the endpoint does not expose account existence via HTTP status or response body (CWE-204). Setting this to False restores the legacy behavior of returning a 400 for unknown accounts; this re-enables the enumeration oracle and is deprecated (will be removed in a future major release). Note: even with the default, a timing side channel may still distinguish existing from non-existing accounts (the existing-account path performs a DB write and fires reset_password_token_created).

• DJANGO_REST_MULTITOKENAUTH_REQUIRE_USABLE_PASSWORD - allows password reset for a user that does not have a usable password (Default: True)

Custom Email Lookup

By default, email lookup is used to find the user instance. You can change that by adding

DJANGO_REST_LOOKUP_FIELD = 'custom_email_field'

into Django settings.py file.

Custom Remote IP Address and User Agent Header Lookup

If your setup demands that the IP adress of the user is in another header (e.g., 'X-Forwarded-For'), you can configure that (using Django Request Headers):

DJANGO_REST_PASSWORDRESET_IP_ADDRESS_HEADER = 'HTTP_X_FORWARDED_FOR'

The same is true for the user agent:

DJANGO_REST_PASSWORDRESET_HTTP_USER_AGENT_HEADER = 'HTTP_USER_AGENT'

Custom Token Generator

By default, a random string token of length 10 to 50 is generated using the RandomStringTokenGenerator class. This library offers a possibility to configure the params of RandomStringTokenGenerator as well as switch to another token generator, e.g. RandomNumberTokenGenerator. You can also generate your own token generator class.

You can change that by adding

DJANGO_REST_PASSWORDRESET_TOKEN_CONFIG = {
    "CLASS": ...,
    "OPTIONS": {...}
}

into Django settings.py file.

RandomStringTokenGenerator

This is the default configuration.

DJANGO_REST_PASSWORDRESET_TOKEN_CONFIG = {
    "CLASS": "django_rest_passwordreset.tokens.RandomStringTokenGenerator"
}

You can configure the length as follows:

DJANGO_REST_PASSWORDRESET_TOKEN_CONFIG = {
    "CLASS": "django_rest_passwordreset.tokens.RandomStringTokenGenerator",
    "OPTIONS": {
        "min_length": 20,
        "max_length": 30
    }
}

It uses os.urandom() to generate a good random string.

RandomNumberTokenGenerator

Security warning: Numeric tokens have a much smaller search space than the default string tokens. The default range (10000–99999, about 90,000 values) can be exhausted in roughly a day at one guess per second against the token-validation or password-confirm endpoint, and faster without effective throttling. Use RandomNumberTokenGenerator only when numeric reset codes are required. If you use it, choose a large range and throttle validate/confirm (see Throttling). For most deployments, RandomStringTokenGenerator remains the safer default.

DJANGO_REST_PASSWORDRESET_TOKEN_CONFIG = {
    "CLASS": "django_rest_passwordreset.tokens.RandomNumberTokenGenerator"
}

Configure the minimum and maximum value as follows. This example produces 10-digit numeric tokens with about 9 billion possible values; use it together with validate/confirm throttling:

DJANGO_REST_PASSWORDRESET_TOKEN_CONFIG = {
    "CLASS": "django_rest_passwordreset.tokens.RandomNumberTokenGenerator",
    "OPTIONS": {
        "min_number": 1000000000,
        "max_number": 9999999999
    }
}

It uses random.SystemRandom().randint() to generate a good random number.

Write your own Token Generator

Please see token_configuration/django_rest_passwordreset/tokens.py for example implementation of number and string token generator.

The basic idea is to create a new class that inherits from BaseTokenGenerator, takes arbitrary arguments (args and kwargs) in the __init__ function as well as implementing a generate_token function.

from django_rest_passwordreset.tokens import BaseTokenGenerator


class RandomStringTokenGenerator(BaseTokenGenerator):
    """
    Generates a random string with min and max length using os.urandom and binascii.hexlify
    """

    def __init__(self, min_length=10, max_length=50, *args, **kwargs):
        self.min_length = min_length
        self.max_length = max_length

    def generate_token(self, *args, **kwargs):
        """ generates a pseudo random code using os.urandom and binascii.hexlify """
        # determine the length based on min_length and max_length
        length = random.randint(self.min_length, self.max_length)

        # generate the token using os.urandom and hexlify
        return binascii.hexlify(
            os.urandom(self.max_length)
        ).decode()[0:length]

Throttling

The endpoint to request a reset password token provides throttling. Per default the throttling rate is 3/day per IP address, applied via the library's ResetPasswordRequestTokenThrottle (a DRF UserRateThrottle scoped to "django-rest-passwordreset-request-token").

The throttling rate can be customized using the REST_FRAMEWORK setting and the scope "django-rest-passwordreset-request-token":

REST_FRAMEWORK = {"DEFAULT_THROTTLE_RATES": {"django-rest-passwordreset-request-token": "5/hour"}}

The request-token throttle classes can also be replaced:

DJANGO_REST_PASSWORDRESET_THROTTLE_CLASSES = [
    "rest_framework.throttling.AnonRateThrottle",
]

By default, this setting is unset and the endpoint uses ResetPasswordRequestTokenThrottle. Setting DJANGO_REST_PASSWORDRESET_THROTTLE_CLASSES = [] delegates the request-token endpoint to DRF's global DEFAULT_THROTTLE_CLASSES instead. If you do this, configure an equivalent global throttle; otherwise you remove the built-in 3/day request-token protection. For ScopedRateThrottle, the request-token scope is "django-rest-passwordreset-request-token".

The token-validation and password-confirm endpoints do not declare their own throttle_classes, so an operator's REST_FRAMEWORK["DEFAULT_THROTTLE_CLASSES"] is respected for those endpoints. In earlier versions, those endpoints declared throttle_classes = () and silently bypassed global throttles.

The request-token endpoint is intentionally different by default: it uses its configured DJANGO_REST_PASSWORDRESET_THROTTLE_CLASSES, so global DEFAULT_THROTTLE_CLASSES do not additionally stack on that endpoint unless you set DJANGO_REST_PASSWORDRESET_THROTTLE_CLASSES = [].

For example, to use DRF's scoped throttling for all three password-reset endpoints:

DJANGO_REST_PASSWORDRESET_THROTTLE_CLASSES = []

REST_FRAMEWORK = {
    "DEFAULT_THROTTLE_CLASSES": [
        "rest_framework.throttling.ScopedRateThrottle",
    ],
    "DEFAULT_THROTTLE_RATES": {
        "django-rest-passwordreset-request-token": "5/hour",
        "django-rest-passwordreset-validate-token": "60/minute",
        "django-rest-passwordreset-confirm": "10/hour",
    },
}

When ScopedRateThrottle is active on any password-reset endpoint, every active scope must have a matching entry in DEFAULT_THROTTLE_RATES. Omitting a rate for django-rest-passwordreset-request-token, django-rest-passwordreset-validate-token, or django-rest-passwordreset-confirm causes the affected endpoint to raise ImproperlyConfigured (HTTP 500).

See also: https://www.django-rest-framework.org/api-guide/throttling/#setting-the-throttling-policy

If you use AnonRateThrottle or UserRateThrottle globally, configure the standard DRF anon and user rates instead.

Compatibility Matrix

This library should be compatible with the latest Django and Django Rest Framework Versions. For reference, here is a matrix showing the guaranteed and tested compatibility.

django-rest-passwordreset Version	Django Versions	Django Rest Framework Versions	Python
0.9.7	1.8, 1.11, 2.0, 2.1	3.6 - 3.9	2.7
1.0	1.11, 2.0, 2.2	3.6 - 3.9	2.7
1.1	1.11, 2.2	3.6 - 3.9	2.7
1.2	2.2, 3.0, 3.1	3.10, 3.11	3.5 - 3.8
1.3	3.2, 4.0, 4.1	3.12, 3.13, 3.14	3.7 - 3.10
1.4	3.2, 4.2, 5.0	3.13, 3.14	3.8 - 3.12
1.5	4.2, 5.0, 5.1	3.15	3.9 - 3.13
1.6 (current)	5.2, 6.0	3.16, 3.17	3.10 - 3.14*

* Django 6.0 is tested on Python 3.12 - 3.14, while Django 5.2 is tested on Python 3.10 - 3.14.

Documentation / Browsable API

This package supports the DRF auto-generated documentation (via coreapi) as well as the DRF browsable API.

To add the endpoints to the browsable API, you can use a helper function in your urls.py file:

from rest_framework.routers import DefaultRouter
from django_rest_passwordreset.urls import add_reset_password_urls_to_router

router = DefaultRouter()
add_reset_password_urls_to_router(router, base_path='api/auth/passwordreset')

Alternatively you can import the ViewSets manually and customize the routes for your setup:

from rest_framework.routers import DefaultRouter
from django_rest_passwordreset.views import ResetPasswordValidateTokenViewSet, ResetPasswordConfirmViewSet, \
    ResetPasswordRequestTokenViewSet

router = DefaultRouter()
router.register(
    r'api/auth/passwordreset/validate_token',
    ResetPasswordValidateTokenViewSet,
    basename='reset-password-validate'
)
router.register(
    r'api/auth/passwordreset/confirm',
    ResetPasswordConfirmViewSet,
    basename='reset-password-confirm'
)
router.register(
    r'api/auth/passwordreset/',
    ResetPasswordRequestTokenViewSet,
    basename='reset-password-request'
)

Known Issues / FAQ

Django 2.1 Migrations - Multiple Primary keys for table ...

Django 2.1 introduced a breaking change for migrations (see Django Issue #29790). We therefore had to rewrite the migration 0002_pk_migration.py such that it covers Django versions before (<) 2.1 and later (>=) 2.1.

Some information is written down in Issue #8.

The reset_password_token_created signal is not fired

You need to make sure that the code with @receiver(reset_password_token_created) is executed by the python interpreter. To ensure this, you have two options:

1. Put the code at a place that is automatically loaded by Django (e.g., models.py, views.py), or

2. Import the file that contains the signal within your app.py ready function:

some_app/signals.py

from django.core.mail import EmailMultiAlternatives
from django.dispatch import receiver
from django.template.loader import render_to_string
from django.urls import reverse

from django_rest_passwordreset.signals import reset_password_token_created


@receiver(reset_password_token_created)
def password_reset_token_created(sender, instance, reset_password_token, *args, **kwargs):
    # ...

some_app/app.py

from django.apps import AppConfig

class SomeAppConfig(AppConfig):
    name = 'your_django_project.some_app'
    verbose_name = 'Some App'

    def ready(self):
        import your_django_project.some_app.signals  # noqa

some_app/init.py

default_app_config = 'your_django_project.some_app.SomeAppConfig'

MongoDB not working

Apparently, the following piece of code in the Django Model prevents MongodB from working:

 id = models.AutoField( 
     primary_key=True 
 ) 

See issue #49 for details.

Contributions

This library tries to follow the unix philosophy of "do one thing and do it well" (which is providing a basic password reset endpoint for Django Rest Framework). Contributions are welcome in the form of pull requests and issues! If you create a pull request, please make sure that you are not introducing breaking changes.

Tests

See folder tests/. Basically, all endpoints are covered with multiple unit tests.

Follow below instructions to run the tests. You may exchange the installed Django and DRF versions according to your requirements. :warning: Depending on your local environment settings you might need to explicitly call python3 instead of python.

# install dependencies
python -m pip install --upgrade pip
pip install -r tests/requirements.txt

# setup environment
pip install -e .

# run tests
cd tests && python manage.py test

Release on PyPi

To release this package on pypi, the following steps are used:

rm -rf dist/ build/
python setup.py sdist
twine upload dist/*