Source Code for Module django.contrib.auth.backends

 1  from django.db import connection 
 2  from django.contrib.auth.models import User 
 3   
 4  try:  
 5      set  
 6  except NameError:  
 7      from sets import Set as set # Python 2.3 fallback 
 8           
 9 -class ModelBackend(object): 
10      """ 
11      Authenticate against django.contrib.auth.models.User 
12      """ 
13      # TODO: Model, login attribute name and password attribute name should be 
14      # configurable. 
15 -    def authenticate(self, username=None, password=None): 
16          try: 
17              user = User.objects.get(username=username) 
18              if user.check_password(password): 
19                  return user 
20          except User.DoesNotExist: 
21              return None 
22   
23 -    def get_group_permissions(self, user_obj): 
24          "Returns a list of permission strings that this user has through his/her groups." 
25          if not hasattr(user_obj, '_group_perm_cache'): 
26              cursor = connection.cursor() 
27              # The SQL below works out to the following, after DB quoting: 
28              # cursor.execute(""" 
29              #     SELECT ct."app_label", p."codename" 
30              #     FROM "auth_permission" p, "auth_group_permissions" gp, "auth_user_groups" ug, "django_content_type" ct 
31              #     WHERE p."id" = gp."permission_id" 
32              #         AND gp."group_id" = ug."group_id" 
33              #         AND ct."id" = p."content_type_id" 
34              #         AND ug."user_id" = %s, [self.id]) 
35              qn = connection.ops.quote_name 
36              sql = """ 
37                  SELECT ct.%s, p.%s 
38                  FROM %s p, %s gp, %s ug, %s ct 
39                  WHERE p.%s = gp.%s 
40                      AND gp.%s = ug.%s 
41                      AND ct.%s = p.%s 
42                      AND ug.%s = %%s""" % ( 
43                  qn('app_label'), qn('codename'), 
44                  qn('auth_permission'), qn('auth_group_permissions'), 
45                  qn('auth_user_groups'), qn('django_content_type'), 
46                  qn('id'), qn('permission_id'), 
47                  qn('group_id'), qn('group_id'), 
48                  qn('id'), qn('content_type_id'), 
49                  qn('user_id'),) 
50              cursor.execute(sql, [user_obj.id]) 
51              user_obj._group_perm_cache = set(["%s.%s" % (row[0], row[1]) for row in cursor.fetchall()]) 
52          return user_obj._group_perm_cache 
53       
54 -    def get_all_permissions(self, user_obj): 
55          if not hasattr(user_obj, '_perm_cache'): 
56              user_obj._perm_cache = set([u"%s.%s" % (p.content_type.app_label, p.codename) for p in user_obj.user_permissions.select_related()]) 
57              user_obj._perm_cache.update(self.get_group_permissions(user_obj)) 
58          return user_obj._perm_cache 
59   
60 -    def has_perm(self, user_obj, perm): 
61          return perm in self.get_all_permissions(user_obj) 
62   
63 -    def has_module_perms(self, user_obj, app_label): 
64          return bool(len([p for p in self.get_all_permissions(user_obj) if p[:p.index('.')] == app_label])) 
65   
66 -    def get_user(self, user_id): 
67          try: 
68              return User.objects.get(pk=user_id) 
69          except User.DoesNotExist: 
70              return None 
71