OpenID authentication


Install the python-openid package:

pip install python-openid

For OpenID support, you need le_social.openid in your INSTALLED_APPS. Make sure you run syncdb.

If you want to access the list of OpenID URLs associated to the current session, add le_social.middleware.OpenIDMiddleware to your MIDDLEWARE_CLASSES. This will add an openids attribute to incoming requests. request.opendis is a list of le_social.openid.utils.OpenID objects.

Basic usage

Define the two URLs to initiate the OpenID connection and the return URL:

from myapp import views

urlpatterns = patterns('',
    url(r'^openid/$', views.begin, name='openid_begin'),
    url(r'^openid/complete/$', views.callback, name='openid_complete'),

And define your two view using the base classes provided by django-le-social:

from django.http import HttpResponse

from le_social.openid import views

class Begin(views.Begin):
    return_url = '/openid/complete/'
    template_name = 'openid.html'

    def failure(self, message):
        return HttpResponse(message)
begin = Begin.as_view()

class Callback(views.Callback):
    return_url = '/openid/complete/'

    def success(self):
        openid_url = self.openid_response.identity_url
        # self.openid_response contains the openid info
        return HttpResponse('Openid association: %s' % openid_url)

    def failure(self, message):
        return HttpResponse(message)
callback = Callback.as_view()

You also need a basic template to render the OpenID form:

<form method="post" action=".">
    {{ form.as_p }}
    {% csrf_token %}
    <input type="submit" value="Sign in">

This code will just return the OpenID URL in case of successful authentication. Usually in the success() method, you would need to store the OpenID URL in the DB, attach it to the currently logged-in user or create a new user object.

The failure() methods are here to handle authentication failures, when the OpenID URL isn’t valid or something goes wrong during the OpenID negociation.

Extension points

Return URL

Both the Begin and Callback views need a return_url attribute. In the examples above the URL is hardcoded but you can provide a dynamically-generated one by defining get_return_url() on the view class or on a mixin shared by your subclasses:

from django.core.urlresolvers import reverse

from le_social.openid import views

class ReturnUrlMixin(object):
    def get_return_url(self):
        return reverse('openid_complete')

class Begin(ReturnUrlMixin, views.Begin):
begin = Begin.as_view()

class Callback(ReturnUrlMixin, views.Callback):
    def success(self):
        return something
callback = Callback.as_view()

Form class

The Begin view is a standard FormView that takes a form_class attribute. The default value is le_social.openid.forms.OpenIDForm, it just asks for a valid URL. If you want to do more specific validation, subclass the form and override clean_openid_url().

Sreg attributes

The sreg_attrs dictionnnary on the Begin class defines which Sreg fields to ask for. By default it is an empty dict but if you don’t specify anything it automatically gets updated to {'optional': ['nickname', 'email']}.

You can alter the sreg_attrs attribute or implement get_sreg_attrs() on the view class.

Attribute Exchange

The ax_attrs attribute on the Begin class defines which AX attributes to request. By default it is an empty list. If you need to set this dynamically, implement get_ax_attrs().

Trust Root

By default the trust root is the root of your website. If you want to change it, alter the trust_root attribute on the Begin class, or define get_trust_root(). Note that trust_root must be a URL without the host (e.g. '/something/'), whereas get_trust_root() must return a full URL, including the protocol and host name.

OpenID objects

With the OpenIDMiddleware, the request gets an openids attribute, a list of the OpenIDs associated to the current session. Each element is a le_social.openid.utils.OpenID instance and has the following information attached:

  • openid: the OpenID URL
  • issued: the time when the association was successful
  • attrs: the OpenID attributes
  • sreg: the Sreg attributes
  • ax: the AX attributes.