Is it possible to get the hostname of the host PC connecting to AppStream or Workspaces?

Hello! In general it is not possible to get the hostname of the local device from which you are connecting.

The CLIENTNAME key is typically filled in when connecting via Remote Desktop; however, AppStream and WorkSpaces are managed application streaming and desktop-as-a-service services. When you connect using the browser- or system-based clients, you are not connecting the same way as you would in an RDP-type connection. That said, it is technically possible to connect to your systems via RDP (and thus get CLIENTNAME), though we usually only suggest this for troubleshooting purposes. As a best practice, we recommend connecting via each service's client for regular, ongoing end-user connections.

WorkSpaces and AppStream are virtual computers in the AWS Cloud. They work the same as traditional physical Windows systems. When you launch software, you are running them on the AppStream instance and/or WorkSpace itself. We would need to learn more about how the application works; however, you may be able to provide the name of the current AppStream instance and/or WorkSpace itself by checking HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\ComputerName\ActiveComputerName. This registry key typically contains the current computer name of the Windows system, which in the case of AppStream and WorkSpaces, would be the name of the specific virtual instance to which you are connected.

Keep in mind that this value may not be consistent across different sessions, particularly with AppStream, so it might be something you would have to dynamically check and update via a script.