# Osso - Open Source SAML SSO
## Backend class
For Django, add this class path to `AUTHENTICATION_BACKENDS`. For other
integrations, use the same class path in the framework-specific backend
setting.
| Backend name | Class path |
|----------------|----------------------------------------|
| `osso` | `social_core.backends.osso.OssoOAuth2` |
Osso is an open source service that handles SAML tenant onboarding, documentation and authentication.
Your application can then consume normalized user profile resources as part of an OAuth 2.0 authorization code grant flow.
Learn more about Osso at [https://ossoapp.com](https://ossoapp.com) or continue below to start consuming your Osso instance from your application via Python Social Auth.
To enable Osso as a backend:
- On your project settings, add Osso on your `AUTHENTICATION_BACKENDS`:
```default
AUTHENTICATION_BACKENDS = (
...
'social_core.backends.osso.OssoOAuth2',
)
```
- Create or update an OAuth Client in your Osso instance, adding a redirect URI to your allow
`http://example.com/complete/osso/` replacing `http://example.com` with your application’s domain.
Grab the `Client ID` and `Client Secret` to use in your application.
- Add these values of `Client ID` and `Client Secret` from Osso in your project settings file.
The `Client ID` should be added on `SOCIAL_AUTH_OSSO_KEY` and the `Client Secret` should be
added on `SOCIAL_AUTH_OSSO_SECRET`. You also need to add your Osso instance base URL as `SOCIAL_AUTH_OSSO_BASE_URL`:
```default
SOCIAL_AUTH_OSSO_KEY = os.getenv('SOCIAL_AUTH_OSSO_KEY')
SOCIAL_AUTH_OSSO_SECRET = os.getenv('SOCIAL_AUTH_OSSO_SECRET')
SOCIAL_AUTH_OSSO_BASE_URL = 'https://demo.ossoapp.com'
```
When constructing your sign in flow, Osso supports passing an `email` or `domain` parameter in order to route
the user to the correct IDP. If you don’t include one of these parameters, and instead implement a button, Osso
will display a hosted login page. Here’s an example login form with `email`:
```html+django
```