from django.contrib.admin.sites import AdminSite


#redefining (extend) the admin class for AdminSite2 to let groups enter in the admins or not
class MyAdminSite2(AdminSite):

    def __init__(self, name=None, app_name='admin', valid_groups=None ):
        """
        Call the default contructor and add valid_groups for the group checking for the admin site
        """
        super(MyAdminSite2, self).__init__()
        self.valid_groups = valid_groups



    def has_permission(self, request):
        """
        Returns True if the given HttpRequest has permission to view
        *at least one* page in the admin site. And checks the groups that are valid for this class
        """
        # return request.user.is_active and request.user.is_staff and request.user.username != 'admin'
        if self.valid_groups != None:
            try:
                #get the groups the user is in and check if on of the groups allowed for this admin site
                #is avaiable in the user groups
                groups = request.user.groups.values_list('name',flat=True)
                for i in self.valid_groups:
                    if i in groups:
                        return True
                return False
            except AttributeError:
                #Wen we logout we don't have user to verify the groups and django throws
                #AttributeError at /XXXXXX/ 'NoneType' object has no attribute '_meta'
                pass
        else:
            return request.user.is_active and request.user.is_staff