1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
|
from django.core.exceptions import ImproperlyConfigured
SESSION_KEY = '_auth_user_id'
BACKEND_SESSION_KEY = '_auth_user_backend'
LOGIN_URL = '/accounts/login/'
REDIRECT_FIELD_NAME = 'next'
def load_backend(path):
i = path.rfind('.')
module, attr = path[:i], path[i+1:]
try:
mod = __import__(module, '', '', [attr])
except ImportError, e:
raise ImproperlyConfigured, 'Error importing authentication backend %s: "%s"' % (module, e)
try:
cls = getattr(mod, attr)
except AttributeError:
raise ImproperlyConfigured, 'Module "%s" does not define a "%s" authentication backend' % (module, attr)
return cls()
def get_backends():
from django.conf import settings
backends = []
for backend_path in settings.AUTHENTICATION_BACKENDS:
backends.append(load_backend(backend_path))
return backends
def authenticate(**credentials):
"""
If the given credentials are valid, return a User object.
"""
for backend in get_backends():
try:
user = backend.authenticate(**credentials)
except TypeError:
# This backend doesn't accept these credentials as arguments. Try the next one.
continue
if user is None:
continue
# Annotate the user object with the path of the backend.
user.backend = "%s.%s" % (backend.__module__, backend.__class__.__name__)
return user
def login(request, user):
"""
Persist a user id and a backend in the request. This way a user doesn't
have to reauthenticate on every request.
"""
if user is None:
user = request.user
# TODO: It would be nice to support different login methods, like signed cookies.
request.session[SESSION_KEY] = user.id
request.session[BACKEND_SESSION_KEY] = user.backend
def logout(request):
"""
Remove the authenticated user's ID from the request.
"""
try:
del request.session[SESSION_KEY]
except KeyError:
pass
try:
del request.session[BACKEND_SESSION_KEY]
except KeyError:
pass
def get_user(request):
from django.contrib.auth.models import AnonymousUser
try:
user_id = request.session[SESSION_KEY]
backend_path = request.session[BACKEND_SESSION_KEY]
backend = load_backend(backend_path)
user = backend.get_user(user_id) or AnonymousUser()
except KeyError:
user = AnonymousUser()
return user
|