Hacking Django Admin, hooks for login/logout.

Question

How do I add hooks to the Django Admin, such that I can execute a function when the user logs in or out?

Answer 1

Django does sadly not send any signals on that events.... But you could make your own custom AuthorizationBackend that enables you to do so:

from django.dispatch import Signal

post_login = Signal(providing_args=['user'])

from django.contrib.auth.backends import ModelBackend
from django.contrib.auth.models import User

class AuthSignalBackend(ModelBackend):
    def authenticate(self, username=None, password=None):
        try:
            user = User.objects.get(username=username)
            if user.check_password(password):
                post_login.send(sender=None, user=user)
                return user
        except User.DoesNotExist:
            return None


def login_handler(sender, **kwargs):
    print "logging in..."        
post_login.connect(login_handler)

To enable it you have to put AUTHENTICATION_BACKENDS = (myapp.mymodule.AuthSignalBackend',) in your settings.py!

Answer 2

I was also looking for an answer to this and ended up going another way. You can use your own views for login and logout, which perform some action and then call the auth views. For login:

def login(request, *args, **kwargs):
    from django.contrib.auth.forms import AuthenticationForm
    if request.method == 'POST':
        form = AuthenticationForm(data=request.POST)
        if form.is_valid():
            # login successful
            do_something()
    from django.contrib.auth.views import login as authlogin
    return authlogin(request, *args, **kwargs)

And for logout:

def logout(request, *args, **kwargs):
    do_something() 
    from django.contrib.auth.views import logout as authlogout
    return authlogout(request, *args, **kwargs)

You can do whatever processing you like in your custom views in place of the do_something placeholders, such as emitting signals, logging log-in and log-out times, etc.

Finally, don't forget to update your urls.py to point to your custom views.

I'm not sure how a custom auth backend can handle logout events, as i eventually gave up on that and tried this instead. Additionally, this approach has the advantage of making available the request object instead of just the user.