[Django]-How to get the list of the authenticated users?

Most reliable solution would only be the something you store when user logs in or logs out. I saw this solution and i think its worth sharing.

models.py

from django.contrib.auth.signals import user_logged_in, user_logged_out

class LoggedUser(models.Model):
    user = models.ForeignKey(User, primary_key=True)

    def __unicode__(self):
        return self.user.username

    def login_user(sender, request, user, **kwargs):
        LoggedUser(user=user).save()

    def logout_user(sender, request, user, **kwargs):
        try:
            u = LoggedUser.objects.get(user=user)
            u.delete()
        except LoggedUser.DoesNotExist:
            pass

    user_logged_in.connect(login_user)
    user_logged_out.connect(logout_user)

views.py

logged_users = LoggedUser.objects.all().order_by('username')

Sounds similiar with this solution, you can create a custom middleware to do it. I found awesome OnlineNowMiddleware here.

Where you will get these;

1. {{ request.online_now }} => display all list of online users.
2. {{ request.online_now_ids }} => display all online user ids.
3. {{ request.online_now.count }} => display total online users.

How to set up?

Create file middleware.py where location of settings.py has been saved, eg:

projectname/projectname/__init__.py
projectname/projectname/middleware.py
projectname/projectname/settings.py

Then following this lines;

from django.core.cache import cache
from django.conf import settings
from django.contrib.auth.models import User
from django.utils.deprecation import MiddlewareMixin

ONLINE_THRESHOLD = getattr(settings, 'ONLINE_THRESHOLD', 60 * 15)
ONLINE_MAX = getattr(settings, 'ONLINE_MAX', 50)


def get_online_now(self):
    return User.objects.filter(id__in=self.online_now_ids or [])


class OnlineNowMiddleware(MiddlewareMixin):
    """
    Maintains a list of users who have interacted with the website recently.
    Their user IDs are available as ``online_now_ids`` on the request object,
    and their corresponding users are available (lazily) as the
    ``online_now`` property on the request object.
    """

    def process_request(self, request):
        # First get the index
        uids = cache.get('online-now', [])

        # Perform the multiget on the individual online uid keys
        online_keys = ['online-%s' % (u,) for u in uids]
        fresh = cache.get_many(online_keys).keys()
        online_now_ids = [int(k.replace('online-', '')) for k in fresh]

        # If the user is authenticated, add their id to the list
        if request.user.is_authenticated:
            uid = request.user.id
            # If their uid is already in the list, we want to bump it
            # to the top, so we remove the earlier entry.
            if uid in online_now_ids:
                online_now_ids.remove(uid)
            online_now_ids.append(uid)
            if len(online_now_ids) > ONLINE_MAX:
                del online_now_ids[0]

        # Attach our modifications to the request object
        request.__class__.online_now_ids = online_now_ids
        request.__class__.online_now = property(get_online_now)

        # Set the new cache
        cache.set('online-%s' % (request.user.pk,), True, ONLINE_THRESHOLD)
        cache.set('online-now', online_now_ids, ONLINE_THRESHOLD)

Finally update your MIDDLEWARE inside file of projectname/projectname/settings.py:

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.cache.UpdateCacheMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.cache.FetchFromCacheMiddleware',
    ....
    # Custom middleware
    'projectname.middleware.OnlineNowMiddleware',
]

For other condition, you can also check the current user is online or not with:

{% if request.user in request.online_now %}
    {# do stuff #}
{% endif %}

There is no easy, built-in way to do what you want that I know of. I’d try a combination of expiring sessions and filtering on last_login. Maybe even write a custom manager for that.