Django: Basic Auth for one view (avoid middleware)

For those that already use django-rest-framework (DRF):

DRF has a BasicAuthentication class which, more-or-less, does what is described in the other answers (see source).

This class can also be used in "normal" Django views.

For example:

from rest_framework.authentication import BasicAuthentication

def my_view(request):
    # use django-rest-framework's basic authentication to get user
    user = None
    user_auth_tuple = BasicAuthentication().authenticate(request)
    if user_auth_tuple is not None:
        user, _ = user_auth_tuple

You can try a custom decorator (as seems to be the recommended way here and here) instead of adding new middleware:

my_app/decorators.py:

import base64

from django.http import HttpResponse
from django.contrib.auth import authenticate
from django.conf import settings


def basicauth(view):
    def wrap(request, *args, **kwargs):
        if 'HTTP_AUTHORIZATION' in request.META:
            auth = request.META['HTTP_AUTHORIZATION'].split()
            if len(auth) == 2:
                if auth[0].lower() == "basic":
                    uname, passwd = base64.b64decode(auth[1]).decode(
                        "utf8"
                    ).split(':', 1)
                    user = authenticate(username=uname, password=passwd)
                    if user is not None and user.is_active:
                        request.user = user
                        return view(request, *args, **kwargs)
        
        response = HttpResponse()
        response.status_code = 401
        response['WWW-Authenticate'] = 'Basic realm="{}"'.format(
            settings.BASIC_AUTH_REALM
        )
        return response
    return wrap

Then use this to decorate your view:

from my_app.decorators import basicauth


@basicauth
def my_view(request):
    ...

This library could be used: https://github.com/hirokiky/django-basicauth

Basic auth utilities for Django.

The docs show how to use it:

Applying decorator to CBVs

To apply @basic_auth_requried decorator to Class Based Views, use django.utils.decorators.method_decorator.

Source: https://github.com/hirokiky/django-basicauth#applying-decorator-to-cbvs

When you do a basic auth request, you're really adding credentials into the Authorization header. Before transit, these credentials are base64-encoded, so you need to decode them on receipt.

The following code snippet presumes that there's only one valid username and password:

import base64

def my_view(request):
    auth_header = request.META.get('HTTP_AUTHORIZATION', '')
    token_type, _, credentials = auth_header.partition(' ')

    expected = base64.b64encode(b'username:password').decode()

    if token_type != 'Basic' or credentials != expected:
        return HttpResponse(status=401)

    # Your authenticated code here:
    ...

If you wish to compare to the username and password of a User model, try the following instead:

def my_view(request):
    auth_header = request.META.get('HTTP_AUTHORIZATION', '')
    token_type, _, credentials = auth_header.partition(' ')

    username, password = base64.b64decode(credentials).split(':')
    try:
        user = User.objects.get(username=username)
    except User.DoesNotExist:
        return HttpResponse(status=401)

    password_valid = user.check_password(password)

    if token_type != 'Basic' or not password_valid:
        return HttpResponse(status=401)

    # Your authenticated code here:
    ...

Please note that this latter version is not extremely secure. At first glance, I can see that it is vulnerable to timing attacks, for example.