[keycloak-dev] Handle case when KC fails to send logout message to some application - KEYCLOAK 782

Hi everyone! I'm a potential GSOC student dreaming of working on "Keycloak - Certificate Management" project. I spent last few days analysing the code, debuging and looking how it really works on the inside. I'd like to fix a bug which I've chosen from Jira. The issue number is KEYCLOAK-782. In OAuth 2.0 specification (RFC6749) I found the following parameters (within item 4.1.2.1. Error Response) : server_error The authorization server encountered an unexpected condition that prevented it from fulfilling the request. (This error code is needed because a 500 Internal Server Error HTTP status code cannot be returned to the client via an HTTP redirect.) error_description OPTIONAL. Human-readable ASCII [USASCII] text providing additional information, used to assist the client developer in understanding the error that occurred. Values for the "error_description" parameter MUST NOT include characters outside the set %x20-21 / %x23-5B / %x5D-7E. So the uri after logout would look like this: ...&error=server_error&error_description=Logout+from+some+apps+failed The error_description could be either human readable description or just an error code. It should be processed on client side. Keycloak.js should be changed to handle it. These params should be added to OIDCLoginProtocol and of course to response when such an error occur. In first loop iterating on userSessions placed in AuthenticationManager.browserLogout there should be saving error when backend logout fails. It could be done by adding a note to userSession and getting it in finishLogout (first, of course, checking if it exists). What do you think about the above mentioned solution? best regards, Michal Choinski