src: add user session detection implementationwinlinux

Detect user login and logout for Linux and Windows.

Report an active interactive session through the /refresh response
so a new ogserver instance can update the session status.

Poll the session change in 5 second intervals in a thread. Use the
same event socket previously used by the old session detection
mechanism to notify a session change.

Use the method check_interactive_session_change in each
ogOperations.py to report the session status.
Return values:
	None: no session changes are found
	True: login
	False: logout

Windows
check_interactive_session_change uses the WMI API to obtain session
information. Obtain the list of sessions associated to interactive
sessions and then filter the sessions with a valid user.

Linux
Check if any user has the DISPLAY or WAYLAND_DISPLAY environment
variable defined as that means there is an interactive session
in execution.

1 files changed, 29 insertions, 1 deletions

diff --git a/src/linux/ogOperations.py b/src/linux/ogOperations.py
index 4728201..10efaa4 100644
--- a/src/linux/ogOperations.py
+++ b/src/linux/ogOperations.py
@@ -7,6 +7,7 @@
 # (at your option) any later version.
 
 import os
+import psutil
 import subprocess
 from subprocess import CalledProcessError
 from src.log import OgError
@@ -15,6 +16,9 @@ from src.ogRest import ThreadState
 
 class OgLinuxOperations:
 
+    def __init__(self):
+        self.session = False
+
     def _restartBrowser(self, url):
         raise OgError('Function not implemented')
 
@@ -66,4 +70,28 @@ class OgLinuxOperations:
         raise OgError('Function not implemented')
 
     def refresh(self, ogRest):
-        return {"status": "LINUX"}
+        if self.session:
+            session_value = 'LINUXS'
+        else:
+            session_value = 'LINUX'
+        return {"status": session_value}
+
+    def check_interactive_session_change(self):
+        old_status = self.session
+        has_logged_user = False
+        for user in psutil.users():
+            if user.terminal:
+                try:
+                    process = psutil.Process(user.pid)
+                    env = process.environ()
+                    if "DISPLAY" in env or "WAYLAND_DISPLAY" in env:
+                        has_logged_user = True
+                        break
+
+                except (psutil.NoSuchProcess, psutil.AccessDenied):
+                    continue
+        self.session = has_logged_user
+
+        if self.session != old_status:
+            return self.session
+        return None