Class UserSession

get sessionId from sessionStorage if sessionId was undefined or null so get sessionId from localStorage

then return promise that resolve sesstionId that setDefaultHeader

parameter 'body' for sending to http return Response as result If status was 200 then checkTimeout will fire.

login and save sessionId into sessionStorage

logout and remove sessionId from localStorage/sessionStorage

save sessionId into localStorage and remove if sessionId was set into null or undefined or ''