refactor v2

app.py

@@ -17,7 +17,7 @@ app = Flask(__name__)
 app.config['SECRET_KEY'] = config.FLASK_CONFIG['secret_key']
 app.config['SEND_FILE_MAX_AGE_DEFAULT'] = config.FLASK_CONFIG.get('static_cache_timeout', 60)
 # Bez Eventlet (deprecated) – prosty tryb wątkowy.
-socketio = SocketIO(app, cors_allowed_origins="*", async_mode="threading", logger=False)
+socketio = SocketIO(app, cors_allowed_origins="*", async_mode='threading', logger=False)
 
 def get_file_hash(filename):
     full_path = os.path.join(app.static_folder, filename)
@@ -291,11 +291,32 @@ def api_outages(phase_id):
     finally:
         client.close()
 
+clients = 0
+task = None
+
+@socketio.on('connect')
+def handle_connect():
+    global clients, task
+    clients += 1
+    if task is None:
+        task = socketio.start_background_task(background_voltage_update)
+
+@socketio.on('disconnect')
+def handle_disconnect():
+    global clients
+    clients = max(0, clients - 1)
+
 def background_voltage_update():
+    global clients
     last_refresh = 0
     refresh_every_s = config.CHART_CONFIG.get("refresh_interval_seconds", 15)
+    interval_s = config.CHART_CONFIG['update_interval'] / 1000.0
 
     while True:
+        if clients == 0:
+            socketio.sleep(1)
+            continue
+
         try:
             voltages = {'timestamp': None}
 
@@ -305,29 +326,21 @@ def background_voltage_update():
                 if res['timestamp']:
                     voltages['timestamp'] = res['timestamp']
 
-            # aktualizacja gauge
             socketio.emit('voltage_update', voltages)
 
-            # cykliczny refresh wykresu + eventów
             now = time.time()
             if now - last_refresh >= refresh_every_s:
                 socketio.emit('refresh_timeseries', {'ts': int(now)})
                 last_refresh = now
 
         except Exception as e:
-            print(f"Worker Error: {e}")
+            app.logger.error(f"Worker Error: {e}")
 
-        #time.sleep(config.CHART_CONFIG['update_interval'] / 1000.0)
+        socketio.sleep(interval_s)
 
 if __name__ == '__main__':
     print("\n" + "="*50)
     print(f"Voltage Monitor API / Port: {config.FLASK_CONFIG['port']}")
     print("="*50 + "\n")
     
-    socketio.start_background_task(background_voltage_update)
-    socketio.run(
-        app,
-        host="0.0.0.0",
-        port=config.FLASK_CONFIG["port"],
-        allow_unsafe_werkzeug=True
-    )
+    socketio.run(app, host='0.0.0.0', port=config.FLASK_CONFIG['port'], allow_unsafe_werkzeug=True)