from django.conf import settings
from django.contrib.auth import REDIRECT_FIELD_NAME, get_user_model, login as auth_login
from django.contrib.auth.forms import AuthenticationForm
from django.contrib.sites.shortcuts import get_current_site
from django.http import HttpResponseRedirect
from django.shortcuts import resolve_url
from django.utils.decorators import method_decorator
from django.utils.http import is_safe_url
from django.views.decorators.cache import never_cache
from django.views.decorators.csrf import csrf_protect
from django.views.decorators.debug import sensitive_post_parameters
from django.views.generic.edit import FormView
class SuccessURLAllowedHostsMixin:
success_url_allowed_hosts = set()
def get_success_url_allowed_hosts(self):
return {self.request.get_host(), *self.success_url_allowed_hosts}
class LoginView(SuccessURLAllowedHostsMixin, FormView):
"""
Display the login form and handle the login action.
"""
form_class = AuthenticationForm
authentication_form = None
redirect_field_name = REDIRECT_FIELD_NAME
template_name = 'registration/login.html'
redirect_authenticated_user = False
extra_context = None
@method_decorator(sensitive_post_parameters())
@method_decorator(csrf_protect)
@method_decorator(never_cache)
def dispatch(self, request, *args, **kwargs):
if self.redirect_authenticated_user and self.request.user.is_authenticated:
redirect_to = self.get_success_url()
if redirect_to == self.request.path:
raise ValueError(
'Redirection loop for authenticated user detected. Check that '
'your LOGIN_REDIRECT_URL doesn\'t point to a login page.'
)
return HttpResponseRedirect(redirect_to)
return super().dispatch(request, *args, **kwargs)
def get_success_url(self):
url = self.get_redirect_url()
return url or resolve_url(settings.LOGIN_REDIRECT_URL)
def get_redirect_url(self):
"""Return the user-originating redirect URL if it's safe."""
redirect_to = self.request.POST.get(
self.redirect_field_name,
self.request.GET.get(self.redirect_field_name, '')
)
url_is_safe = is_safe_url(
url=redirect_to
)
return redirect_to if url_is_safe else ''
def get_form_class(self):
return self.authentication_form or self.form_class
def get_form_kwargs(self):
kwargs = super().get_form_kwargs()
kwargs['request'] = self.request
return kwargs
def form_valid(self, form):
"""Security check complete. Log the user in."""
auth_login(self.request, form.get_user())
return HttpResponseRedirect(self.get_success_url())
def get_context_data(self, **kwargs):
context = super().get_context_data(**kwargs)
current_site = get_current_site(self.request)
context.update({
self.redirect_field_name: self.get_redirect_url(),
'site': current_site,
'site_name': current_site.name,
**(self.extra_context or {})
})
return context
