[All] Add post_logout_redirect_uri configuration

[pylanglois]

To logout, the openid specs requires a id_token_hint as parameter which is provided along with the access_token. So I added that value to the auth_state. After logout, it is possible to provide a URI where the user is redirected. This URI can be set with the traitlets post_logout_redirect_uri.

https://openid.net/specs/openid-connect-rpinitiated-1_0.html#RPLogout

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[pylanglois]

Note that you need to request the 'openid' scope to get an 'id_token'

c.GenericOAuthenticator.scope = ["openid"]

[nguyentritai2906]

@GeorgianaElena Any update on this? :)

[n0k0m3]

Quick workaround without the need of id_token_hint: use client_id=<clientid>. This will allows logout to work, however user will need to confirm on Keycloak/OAuth provider side to logout (2 clicks instead of just 1)

[pylanglois]

For some reason, extra_params with client_id and secret needs to be present in your config file.

c.GenericOAuthenticator.extra_params = { "client_id": "your-client", "client_secret": "your-secret", }