Refactor CourseLiveSessionRoomCreateAPIView for improved session management and room creation logic

- Enhanced session handling by checking for active sessions before creating a new room in PlugNMeet, reducing unnecessary API calls.
- Implemented logic to reactivate ended sessions and log relevant actions for better traceability.
- Added conditional room creation to avoid duplicate rooms, improving overall efficiency and user experience.

apps/course/views/live_session.py

@@ -53,89 +53,94 @@ class CourseLiveSessionRoomCreateAPIView(GenericAPIView):
         # 2. Setup ID and Metadata
         room_id = f"room-{course.id}-imamjavad"
         subject = f"{course.title} Live Session"
-        metadata = self._build_metadata(subject)
-
-        # 3. Use your CLEAN PlugNMeetClient
-        try:
-            client = PlugNMeetClient() # Loads keys from settings automatically
-            
-            # This uses the keys internally to talk to the server
-            plugnmeet_response = client.create_room({
-                'room_id': room_id,
-                'metadata': metadata,
-            })
-            
-            # 4. Generate the JOIN TOKEN (The Entry Ticket)
-            # Users CANNOT enter without this.
-            token_payload = {
-                "room_id": room_id,
-                "user_info": {
-                    "name": f"{request.user.first_name} {request.user.last_name}",
-                    "user_id": str(request.user.id),
-                    "is_admin": True,
-                    "is_hidden": False
-                }
-            }
-            
-            # Check if your client has a method for this, otherwise use manual:
-            # access_token = client.get_join_token(token_payload)
-            # If not, we do it manually here using the SAME secret from settings:
-            
-            pnm_token = jwt.encode(
-                {
-                    "iss": settings.PLUGNMEET_API_KEY,
-                    "exp": int(time.time()) + 3600,
-                    "sub": str(request.user.id),
-                    **token_payload
-                },
-                settings.PLUGNMEET_API_SECRET,
-                algorithm="HS256"
-            )
-
-        except Exception as exc:
-            logger.error(f"PlugNMeet Error: {exc}")
-            raise AppAPIException({'message': str(exc)}, status_code=500)
-
-        # 5. Database Logic
+        
+        # 3. Database Logic - Check FIRST before calling PlugNMeet
         # Strategy: 
         # 1. Try to find active session (ended_at is NULL)
         # 2. If not found, try to find ended session with same room_id and reactivate it
         # 3. If not found, create new session
+        session = None
+        needs_room_creation = False
+        
         try:
             # Try to get active session first
             session = CourseLiveSession.objects.get(
                 course=course, room_id=room_id, ended_at__isnull=True
             )
-            created = False
-            logger.info(f"[LiveSession Create] Reusing active session - session_id={session.id} room_id={room_id}")
+            needs_room_creation = False
+            logger.info(f"[LiveSession Create] Found active session - session_id={session.id} room_id={room_id}")
         except CourseLiveSession.DoesNotExist:
             # No active session, check if there's an old one with same room_id
             try:
                 session = CourseLiveSession.objects.get(
                     course=course, room_id=room_id
                 )
-                # Reactivate the old session
+                # Reactivate the old session and mark for room recreation
                 session.ended_at = None
                 session.started_at = timezone.now()
                 session.subject = subject
                 session.save(update_fields=['ended_at', 'started_at', 'subject', 'updated_at'])
-                created = False
+                needs_room_creation = True
                 logger.info(f"[LiveSession Create] Reactivated ended session - session_id={session.id} room_id={room_id}")
             except CourseLiveSession.DoesNotExist:
-                # No session exists at all, create new one
+                # No session exists at all, create new one and mark for room creation
                 session = CourseLiveSession.objects.create(
                     course=course,
                     room_id=room_id,
                     subject=subject,
                     started_at=timezone.now()
                 )
-                created = True
+                needs_room_creation = True
                 logger.info(f"[LiveSession Create] Created new session - session_id={session.id} room_id={room_id}")
 
+        # 4. Create room in PlugNMeet ONLY if needed
+        if needs_room_creation:
+            metadata = self._build_metadata(subject)
+            try:
+                client = PlugNMeetClient()
+                plugnmeet_response = client.create_room({
+                    'room_id': room_id,
+                    'metadata': metadata,
+                })
+                logger.info(f"[LiveSession Create] Room created in PlugNMeet - room_id={room_id}")
+            except Exception as exc:
+                logger.error(f"[LiveSession Create] PlugNMeet Error: {exc}")
+                # If room creation fails, revert the session changes
+                if session.ended_at is None:
+                    session.ended_at = timezone.now()
+                    session.save(update_fields=['ended_at', 'updated_at'])
+                raise AppAPIException({'message': f'Failed to create room: {str(exc)}'}, status_code=500)
+        else:
+            logger.info(f"[LiveSession Create] Skipping room creation - room already exists - room_id={room_id}")
+
+        # 5. Generate the JOIN TOKEN (The Entry Ticket)
+        token_payload = {
+            "room_id": room_id,
+            "user_info": {
+                "name": f"{request.user.first_name} {request.user.last_name}",
+                "user_id": str(request.user.id),
+                "is_admin": True,
+                "is_hidden": False
+            }
+        }
+        
+        pnm_token = jwt.encode(
+            {
+                "iss": settings.PLUGNMEET_API_KEY,
+                "exp": int(time.time()) + 3600,
+                "sub": str(request.user.id),
+                **token_payload
+            },
+            settings.PLUGNMEET_API_SECRET,
+            algorithm="HS256"
+        )
+
+        logger.info(f"[LiveSession Create] Success - session_id={session.id} room_id={room_id} user_id={request.user.id}")
+
         return Response({
             'success': True,
             'session': {'id': session.id, 'room_id': session.room_id},
-            'access_token': pnm_token  # <--- REQUIRED for frontend
+            'access_token': pnm_token
         }, status=201)