Remote User Authentication is a way to authenticate users in Django Rest Framework (DRF) using a third-party authentication provider, such as an OAuth 2.0 provider like Google or Facebook. This allows users to log in to your DRF application using their existing credentials from another service.

To implement Remote User Authentication in DRF, you need to configure your project’s settings to include the relevant authentication backend. This can be done in the AUTHENTICATION_BACKENDS setting in your settings.py file.

Here’s an example of how to configure Remote User Authentication using Google as the OAuth 2.0 provider:

# settings.py
AUTHENTICATION_BACKENDS = (
    'django.contrib.auth.backends.RemoteUserBackend',
)

# oauth2_provider settings
INSTALLED_APPS = (
    ...
    'oauth2_provider',
    ...
)

MIDDLEWARE = [
    ...
    'oauth2_provider.middleware.OAuth2TokenMiddleware',
    ...
]

AUTHENTICATION_BACKENDS = (
    'oauth2_provider.backends.OAuth2Backend',
    'django.contrib.auth.backends.RemoteUserBackend',
)

# oauth2_provider authentication settings
OAUTH2_PROVIDER = {
    'ACCESS_TOKEN_EXPIRE_SECONDS': 3600,
    'OAUTH2_BACKEND_CLASS': 'oauth2_provider.oauth2_backends.JSONOAuthLibCore',
    'SCOPES': {
        'read': 'Read scope',
        'write': 'Write scope',
    }
}

In the above example, we have included the RemoteUserBackend in the AUTHENTICATION_BACKENDS setting, which is a built-in backend that authenticates users based on the value of the REMOTE_USER header in the HTTP request. We have also included the OAuth2Backend from the oauth2_provider package, which is responsible for handling the OAuth 2.0 authentication flow with Google.

Additionally, we have installed the oauth2_provider package and added its middleware to the MIDDLEWARE setting. We have also configured the OAUTH2_PROVIDER setting with some parameters, such as the access token expiry time, the OAuth 2.0 backend class, and the allowed scopes.

To actually use the Remote User Authentication, you’ll need to configure your reverse proxy to set the REMOTE_USER header to the value of the authenticated user’s username. Once this is done, your DRF application should be able to authenticate users using the Remote User Authentication method.


A small project on Remote User Authentication in Django Rest Framework:

1. Create a new Django project and app:

$ django-admin startproject remotetest
$ cd remotetest
$ python manage.py startapp api

2. Add the api app to the INSTALLED_APPS setting in settings.py.

3. Configure the RemoteUserBackend authentication backend by adding it to the AUTHENTICATION_BACKENDS setting in settings.py:

# settings.py
AUTHENTICATION_BACKENDS = (
    'django.contrib.auth.backends.RemoteUserBackend',
)

4. Create a views.py file in the api app and define a simple view that returns a response with the username of the authenticated user:

# api/views.py
from django.http import HttpResponse

def hello(request):
    return HttpResponse(f'Hello, {request.user.username}!')

5. Add a URL pattern for the hello view in the urls.py file of the api app:

# api/urls.py
from django.urls import path
from . import views

urlpatterns = [
    path('hello/', views.hello),
]

6. Create a simple reverse proxy server to set the REMOTE_USER header. This can be done using the http.server module in Python:

# proxy.py
import http.server
import socketserver

class Proxy(http.server.SimpleHTTPRequestHandler):
    def do_GET(self):
        self.headers['REMOTE_USER'] = 'johndoe'
        return super().do_GET()

with socketserver.TCPServer(("", 8000), Proxy) as httpd:
    print("serving at port 8000")
    httpd.serve_forever()

This reverse proxy server sets the REMOTE_USER header to the value johndoe for all incoming GET requests.

7. Start the reverse proxy server and the Django development server:

$ python proxy.py
$ python manage.py runserver

8. Open a web browser and navigate to http://localhost:8000/hello/. You should see the message “Hello, johndoe!” in the response, indicating that the Remote User Authentication has worked successfully.

Note that this is a very basic example, and in a real-world scenario, you would need to use a more robust authentication mechanism, such as OAuth 2.0, to handle user authentication securely. Additionally, you would also need to configure your web server to set the REMOTE_USER header for incoming requests.

GitHub Link:

https://github.com/saikumar248