django-urlcrypt

django-urlcrypt encrypts information in urls, such as login credentials.

For example, assume I have url patterns that looks like this:

urlpatterns = patterns('',
    url(r'^inbox/$', 'message_inbox', name='message_inbox'), 
    (r'^r/', include('urlcrypt.urls')),
)

I can use django-urlcrypt to generate a url for a user that looks like:

http://www.mydomain.com/r/TkNJBkNFAghDWkdFGPUAQEfcDUJfEBIREgEUFl1BQ18IQkdDUUcPSh4ADAYAWhYKHh8KHBsHEw

and will automatically log that person in and redirects them to /inbox/.

Installation

1. easy_install django-urlcrypt or pip install django-urlcrypt
2. Add urlcrypt to your INSTALLED_APPS
3. In settings.py add 'urlcrypt.auth_backends.UrlCryptBackend' to AUTHENTICATION_BACKENDS

4. In urls.py add:

   (r'^r/', include('urlcrypt.urls')),

5. (recommended) If you wish to use RSA encryption on your tokens, generate a private key with ssh-keygen -t rsa -f <path to private key> if you don't already have one, and then set the path to the private key as URLCRYPT_PRIVATE_KEY_PATH. RSA encryption makes the token much longer but is more secure. The pycrypto library is required.

Usage

In a view:

from django.core.urlresolvers import reverse
from urlcrypt import lib as urlcrypt

token = urlcrypt.generate_login_token(user, reverse('message_inbox'))
encoded_url = reverse('urlcrypt_redirect', args=(token,))
# yours will look slightly different because you have a different SECRET_KEY, but approximately 
# encoded_url == /r/TkNJBkNFAghDWkdFGPUAQEfcDUJfEBIREgEUFl1BQ18IQkdDUUcPSh4ADAYAWhYKHh8KHBsHEw

In a template:

{% load urlcrypt_tags %}
<a href="{% encoded_url user message_inbox %}">click me to log in as {{user.username}} and go to {% url message_inbox %}</a>

Advanced lib usage:

from urlcrypt import lib as urlcrypt

message = {
    'url': u'/users/following/', 
    'user_id': '12345'
}

token = urlcrypt.encode_token((message['user_id'], message['url']))
decoded_message = urlcrypt.decode_token(token, ('user_id', 'url', 'timestamp'))

>>> print token
TkNJBkNFAghDWkdFGPUAQEfcDUJfEBIREgEUFl1BQ18IQkdDUUcPSh4ADAYAWhYKHh8KHBsHEw

>>> print decoded_message
{'url': '/users/following/', 'user_id': '12345'}

Settings

• URLCRYPT_LOGIN_URL
  • default: LOGIN_URL
  • If urlcrypt authentication fails, redirects to URLCRYPT_LOGIN_URL.
• URLCRYPT_RATE_LIMIT
  • default: 60
  • The number of urlcrypt requests a unique visitor is allowed to make per minute.
• URLCRYPT_PRIVATE_KEY_PATH
  • default: None
  • The path to the RSA private key file in PEM format. If None, RSA encryption will not be used.
• RUNNING_TESTS
  • default: False
  • Set RUNNING_TESTS to True when running the urlcrypt tests.

Credits

David Ziegler

Christopher Hesse