lower max sessions

app.py

@@ -25,7 +25,7 @@ WPM_WINDOW = 10  # seconds for running mean calculation
 CALIBRATION_PERIOD = 5  # seconds before showing WPM
 SESSION_TIMEOUT = int(os.environ.get("SESSION_TIMEOUT", "30"))      # Max 30s per session
 INACTIVITY_TIMEOUT = int(os.environ.get("INACTIVITY_TIMEOUT", "10"))  # Close after 10s silence
-MAX_CONCURRENT_SESSIONS = int(os.environ.get("MAX_SESSIONS", "150"))
+MAX_CONCURRENT_SESSIONS = int(os.environ.get("MAX_SESSIONS", "50"))
 
 # Global config (shared across users)
 ws_url = ""
@@ -469,33 +469,37 @@ def auto_start_recording(session):
 
 
 def stop_session(session_id):
-    """Stop the websocket connection but keep the transcript."""
-    session = ensure_session(session_id)
-    
-    if not session.is_running:
-        # Already stopped
-        return get_transcription_html(session.transcription_text, session.status_message, session.current_wpm), session.session_id
-    
-    session.is_running = False
-    session.last_audio_time = None
+    """Stop the websocket connection and invalidate the session.
     
-    # Cancel the running task if any
-    if session._task is not None:
-        session._task.cancel()
-        session._task = None
-    
-    # Remove from active sessions
-    with _sessions_lock:
-        _active_sessions.pop(session.session_id, None)
-        active_count = len(_active_sessions)
+    Returns None for session_id so a fresh session is created on next recording.
+    This prevents duplicate session issues when users stop and restart quickly.
+    """
+    session = ensure_session(session_id)
+    old_transcript = session.transcription_text
+    old_wpm = session.current_wpm
     
-    print(f"Mic stopped - session {session.session_id[:8]} ended. Active sessions: {active_count}")
+    if session.is_running:
+        session.is_running = False
+        session.last_audio_time = None
+        
+        # Cancel the running task if any
+        if session._task is not None:
+            session._task.cancel()
+            session._task = None
+        
+        # Remove from active sessions
+        with _sessions_lock:
+            _active_sessions.pop(session.session_id, None)
+            active_count = len(_active_sessions)
+        
+        print(f"Mic stopped - session {session.session_id[:8]} ended. Active sessions: {active_count}")
     
-    # Keep the transcript but mark as ready for new session
-    session.status_message = "ready"
-    session.session_start_time = None
+    # Remove from registry - the session is done
+    cleanup_session(session.session_id)
     
-    return get_transcription_html(session.transcription_text, session.status_message, session.current_wpm), session.session_id
+    # Return None for session_id - a fresh session will be created on next recording
+    # This ensures no duplicate sessions when users stop/start quickly
+    return get_transcription_html(old_transcript, "ready", old_wpm), None
 
 
 def clear_history(session_id):
@@ -528,6 +532,18 @@ def clear_history(session_id):
 
 def process_audio(audio, session_id):
     """Process incoming audio and queue for streaming."""
+    # Check capacity early - if at max and this is a new user, reject immediately
+    with _sessions_lock:
+        at_capacity = len(_active_sessions) >= MAX_CONCURRENT_SESSIONS
+        is_active_user = session_id and any(s.session_id == session_id for s in _active_sessions.values())
+    
+    if at_capacity and not is_active_user:
+        return get_transcription_html(
+            "The server is currently at capacity, try again later.", 
+            "error", 
+            ""
+        ), session_id
+    
     # Always ensure we have a valid session first
     try:
         session = ensure_session(session_id)