Hi, I am interested in Gluu SSO solution, our DevOps has deployed Gluu server along with OXD server(purchased license) to use their API for authentication purposes. The main requirements for authentication(and user management as well) is the absence of redirection from our resource to SSO provider, so we just want to use Gluu APIs for authentication. So I have integrated org.xdi.oxd-java:2.4.4.Final library in our back-end and performed next steps: 1) Register our application as OpenID client via CommandType.REGISTER_SITE command an obtained OXD_ID; 2) Update registration with the client id, client secret via CommandType.UPDATE_SITE command, BTW I haven't found how to do this from Gluu server UI; 3) Create test user from Gluu UI; 4) Send CommandType.AUTHORIZATION_CODE_FLOW command with required params; 5) Get not verbose response: {"error":"internal_error","error_description":"Unknown internal server error occurs."}; Here the my code snippet: ``` final AuthorizationCodeFlowParams commandParams = new AuthorizationCodeFlowParams(); commandParams.setOxdId(OXD_ID); commandParams.setClientId(CLIENT_ID); commandParams.setClientSecret(CLIENT_SECRET); commandParams.setNonce(UUID.randomUUID().toString()); commandParams.setRedirectUrl("https://gluu-de.local/"); commandParams.setScope("openid"); commandParams.setUserId("Test"); commandParams.setUserSecret("P@ssw0rd"); final Command command = new Command(CommandType.AUTHORIZATION_CODE_FLOW); command.setParamsObject(commandParams); String accessToken = client.send(command).dataAsResponse(AuthorizationCodeFlowResponse.class).getAccessToken(); ``` From oxd-server.log: ``` ReadResult{m_command='{"command":"authorization_code_flow","params":{"scope":"openid","nonce":"1b1b3f4c-5ee5-4765-b3e8-262e5ffb092c","acr":null,"oxd_id":"5ceb7c97-4e02-4133-a391-66ad0a2de4e9","redirect_url":"https://gluu-de.local/","client_id":"IvaaS","client_secret":"ivaas_secret","user_id":"Test User","user_secret":"P@ssw0rd"}}', m_leftString=''} 2017-10-26 20:38:14,600 TRACE [org.xdi.oxd.server.Processor] Command: {"command":"authorization_code_flow","params":{"scope":"openid","nonce":"1b1b3f4c-5ee5-4765-b3e8-262e5ffb092c","acr":null,"oxd_id":"5ceb7c97-4e02-4133-a391-66ad0a2de4e9","redirect_url":"https://gluu-de.local/","client_id":"IvaaS","client_secret":"ivaas_secret","user_id":"Test User","user_secret":"P@ssw0rd"}} 2017-10-26 20:38:14,601 TRACE [org.xdi.oxd.server.service.HttpService] Created TRUST_ALL client. 2017-10-26 20:38:14,622 DEBUG [org.xdi.oxd.server.op.AuthorizationCodeFlowOperation] Authorization code is blank. 2017-10-26 20:38:14,622 TRACE [org.xdi.oxd.server.Processor] Send back response: {"status":"error","data":{"error":"internal_error","error_description":"Unknown internal server error occurs."}} 2017-10-26 20:38:14,622 ERROR [org.xdi.oxd.server.SocketProcessor] Quit. Enable to process command. ``` I have investigated oxd server sources and found that while proccessing AUTHORIZATION_CODE_FLOW command, OXD prepare AuthorizeClient with request and execute it. If authorizationCode property in response is blank, "Authorization code is blank." message is printed(what I exactly see in the log) and null response is returned, I assume that it lead to "Unknown internal server error occurs" for client . Could you please suggest where did I go wrong?How to resolve this issue? Thank you in advance