import urllib
from django.conf import settings
from django.contrib.auth import REDIRECT_FIELD_NAME
from django.http import HttpResponseRedirect

def allow_anonymous(view_func):
  view_func.allow_anonymous = True
  return view_func

class RequireLogin:
  def process_view(self, request, view_func, view_args, view_kwargs):
    if request.path != settings.LOGIN_URL and \
      not request.user.is_authenticated() and \
      not getattr(view_func, 'allow_anonymous', False):
      url = '%s?%s=%s' % (settings.LOGIN_URL, REDIRECT_FIELD_NAME, \
                          urllib.quote(request.get_full_path()))
      return HttpResponseRedirect(url)