I want each time a user logs out from my application its session in the Reporting REST Service also to expire. I tried to perform the Unregister Client request with a custom code. However, I need the clientId and there is no straightforward way to get its value from the viewer.
It turns out that the Reporting REST Service keeps its own client sessions that are different from the hosting application sessions. For that reason, the Telerik Reporting REST Service doesn't know whether a user is logged in/out in the main application. Therefore, a Logout functionality in the viewer will be beneficial for scenarios like the described one.