# OpenID ## 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 | |----------------|-------------------------------------------| | `openid` | `social_core.backends.open_id.OpenIdAuth` | [OpenID](http://openid.net/) support is simpler to implement than [OAuth](http://oauth.net/). Google and Yahoo providers are supported by default, others are supported by POST method providing endpoint URL. The generic OpenID backend stores the identity URL asserted by the provider as the user’s unique identifier. Because this identifier is protocol-derived rather than selected from a response mapping, the generic `ID_KEY` setting does not apply. ## Session and provider binding All OpenID backends require a positive assertion to match backend-scoped discovery state from the browser session that initiated authentication. When the framework supports restoring sessions, only a session identifier carried by the provider-signed `openid.return_to` can select that session. Missing or mismatched state requires the user to restart authentication. The generic `openid` backend remains provider-selectable because the application user supplies its provider URL. Backends configured for one provider additionally require the callback and verified provider endpoints to match the exact HTTPS endpoint discovered at initiation. This applies to the bundled Ubuntu, openSUSE, Yandex, Launchpad, Fedora, Belgium eID, OpenStack, OpenInfra, LiveJournal, and Steam backends. Custom backends with a fixed `URL` receive provider binding automatically. A custom backend that computes a fixed-provider URL in `openid_url()` must override `requires_openid_provider_binding()` to return `True`. Provider discovery URLs and discovered provider endpoints must use HTTPS; there is no setting to disable this validation. Custom strategies that implement session restoration must restore the complete OpenID session state and update session-derived pipeline arguments, including the authenticated user. [OpenID](http://openid.net/) backends can store extra data in `UserSocialAuth.extra_data` field by defining a set of values names to retrieve from any of the used schemas, AttributeExchange and SimpleRegistration. As their keywords differ we need two settings. Settings is per backend, so we have two possible values for each one. Name is dynamically checked using uppercase backend name as prefix: ```default SOCIAL_AUTH__SREG_EXTRA_DATA SOCIAL_AUTH__AX_EXTRA_DATA ``` Example: ```default SOCIAL_AUTH_GOOGLE_SREG_EXTRA_DATA = [(..., ...)] SOCIAL_AUTH_GOOGLE_AX_EXTRA_DATA = [(..., ...)] ``` Settings must be a list of tuples mapping value name in response and value alias used to store. A third value (boolean) is supported to, it’s purpose is to signal if the value should be discarded if it evaluates to `False`, this is to avoid replacing old (needed) values when they don’t form part of current response. If not present, then this check is avoided and the value will replace any data. ## Username The [OpenID](http://openid.net/) backend will check for a `username` key in the values returned by the server, but default to `first-name` + `last-name` if that key is missing. It’s possible to indicate the username key in the values If the username is under a different key with a setting, but backends should have defined a default value. For example: ```default SOCIAL_AUTH_FEDORA_USERNAME_KEY = 'nickname' ``` This setting indicates that the username should be populated by the `nickname` value in the Fedora [OpenID](http://openid.net/) provider.