There are several best practices regarding the logout process in Ory, particularly when using the OpenID Connect (OIDC) and Ory Kratos. 1. Logout Flow in Ory Kratos: To ensure that requests work correctly for the browser flow, use the

-c

flag to store the cookies in a file. On subsequent requests, you can use the

-b

flag to read the cookies from the file. The logout request can be made using a DELETE request with the session token. Here is an example of such a request:

bash curl -X DELETE \    -H "Content-Type: application/json" \    -d '{"session_token":"<session_token>"}' \    https://{project.slug}.<http://projects.oryapis.com/self-service/logout/api|projects.oryapis.com/self-service/logout/api>

[Source](https://www.ory.sh/docs/kratos/bring-your-own-ui/custom-ui-basic-integration#logout-flow) 2. Logout in OIDC: The

id_token_hint

is an optional query parameter that can be provided in the logout request to indicate which OpenID Connect ID Token was used to authenticate the user. This parameter is useful for identifying the user's session and ensuring that the user is properly logged out. It is recommended to always send the

id_token_hint

parameter in the logout request to avoid issues if possible. [Source](https://www.ory.sh/docs/oauth2-oidc/oidc-logout#send-the-id-token-in-id_token_hint) 3. Redirect after Logout: The

post_logout_redirect_uri

parameter in the OpenID Connect front and back-channel logout flow is used to redirect the user's browser to a specified URL after the logout process is complete. The OAuth 2.0 Client should follow these steps: - Allow the `post_logout_redirect_uri`: Each OAuth 2.0 Client can whitelist a list of URIs that can be used as the

post_logout_redirect_uri

parameter value using the

post_logout_redirect_uris

field. - Set the

post_logout_redirect_uri

parameter value in the logout request. - Set the

state

parameter value in the logout request: This value should be a random string used to maintain state between the logout request and the response. - Set the

id_token_hint

parameter value in the logout request: This value should be set to the ID Token that was issued by Ory OAuth2 & OpenID Connect to the user during the authentication process. [Source](https://www.ory.sh/docs/oauth2-oidc/oidc-logout#redirect-after-logout) 4. Logout Logic Diagram: There is a diagram that explains the different parameters and expected behavior of the logout flow. [Source](https://www.ory.sh/docs/oauth2-oidc/oidc-logout#logout-logic-diagram) Please refer to the provided sources for more detailed information.

The decision to revoke all sessions or just the current one during logout depends on the specific requirements of your application. Both options have their use cases: 1. Revoke only the current session: This is the standard behavior for most applications. When a user logs out, only the current session is terminated, and the user remains logged in on any other devices. This is useful for applications where users are likely to be logged in on multiple devices and don't want to be logged out of all of them every time they log out on one. In Ory, you can use the self-service logout API to revoke the current session. [Source](https://www.ory.sh/docs/kratos/session-management/list-revoke-get-sessions#revoking-a-specific-session) 2. Revoke all sessions: This is a more secure option that can be used to ensure that a user is only logged in on one device at a time. If a user logs in on a new device, all other sessions are revoked, forcing the user to log in again on any other devices. This can be useful for applications that handle sensitive data and want to minimize the risk of unauthorized access. In Ory, you can use the revoke sessions API to revoke all sessions other than the current one. [Source](https://www.ory.sh/docs/kratos/session-management/list-revoke-get-sessions#revoking-all-other-sessions) Additionally, Ory provides the

revoke_active_sessions

action which can be used to log out a user from all other active sessions. This ensures that every user has exactly one active session and device at a time. [Source](https://www.ory.sh/docs/actions/revoke-active-sessions) Remember, the choice between these options depends on the specific needs of your application and its users.