Refactor sensor data publishing and health check server configuration. Updated MQTT topic structure for individual data points, improved error handling, and added garbage collection to manage memory. Enhanced logging for health check server accessibility and sensor status updates.

sensor_bridge.py

@@ -1,6 +1,7 @@
 import logging
 import json
 import time
+import gc  # Add garbage collection
 from datetime import datetime, timezone
 from pymodbus.client import ModbusTcpClient
 from pymodbus.exceptions import ModbusException
@@ -31,7 +32,7 @@ def on_publish(client, userdata, mid):
 def read_and_publish_data(mqtt_client, modbus_client, host_info):
     """Read data from Modbus and publish to MQTT"""
     try:
-        # Check and establish Modbus connection
+        # Check and establish Modbus connection with explicit timeout
         if not modbus_client.is_socket_open():
             logging.info(f"Attempting to connect to {host_info['ip']}:{MODBUS_PORT}")
             connection_result = modbus_client.connect()
@@ -52,6 +53,13 @@ def read_and_publish_data(mqtt_client, modbus_client, host_info):
     except Exception as e:
         logging.error(f"Unexpected error from {host_info['ip']}: {e}", exc_info=True)
         return False
+    finally:
+        # Ensure connection is closed after each operation to prevent resource leaks
+        try:
+            if modbus_client and modbus_client.is_socket_open():
+                modbus_client.close()
+        except Exception as e:
+            logging.warning(f"Error closing modbus connection for {host_info['ip']}: {e}")
 
 def read_and_publish_temperature_humidity(mqtt_client, modbus_client, host_info):
     """Read temperature and humidity sensors"""
@@ -74,39 +82,45 @@ def read_and_publish_temperature_humidity(mqtt_client, modbus_client, host_info)
         humidity = raw_hum * 100 / 1000  # Correct formula: 0% to 100% RH
         logging.info(f"Raw humidity from {host_info['ip']}: {raw_hum}, Corrected: {humidity:.1f}%RH")
 
-        # Prepare new topic structure: Location/{location_name}/{sensor_type}/data
+        # Prepare new topic structure: Location/{location_name}/{type}/...
         location = host_info["location"]
         sensor_type = "temperature-humidity"
         current_time = datetime.now(timezone.utc).strftime("%Y-%m-%d %H:%M:%S")
         
-        # Create topic for combined data
-        data_topic = f"Location/{location}/{sensor_type}/data"
+        # Create base topic path
+        base_topic = f"Location/{location}/{sensor_type}"
         
-        # Create JSON payload with all data and status
-        payload = {
-            "timestamp": current_time,
-            "location": location,
-            "sensor_type": sensor_type,
-            "ip": host_info["ip"],
-            "status": "online",
-            "data": {
-                "temperature": round(temperature, 1),
-                "humidity": round(humidity, 1)
-            }
-        }
+        # Publish to individual topics
+        topics_data = [
+            (f"{base_topic}/Time", current_time),
+            (f"{base_topic}/Status", "online"),
+            (f"{base_topic}/Data/temperature", round(temperature, 1)),
+            (f"{base_topic}/Data/humidity", round(humidity, 1))
+        ]
         
-        # Publish combined data as JSON
-        result = mqtt_client.publish(data_topic, json.dumps(payload))
-        result.wait_for_publish()
+        # Publish all data
+        all_published = True
+        for topic, value in topics_data:
+            try:
+                # Convert value to string for MQTT
+                payload = str(value)
+                result = mqtt_client.publish(topic, payload)
+                result.wait_for_publish()
+                
+                if result.is_published():
+                    logging.info(f"Published to '{topic}': {payload}")
+                else:
+                    logging.error(f"Failed to publish to '{topic}': {payload}")
+                    all_published = False
+            except Exception as e:
+                logging.error(f"Error publishing to '{topic}': {e}")
+                all_published = False
         
-        logging.info(f"Published to '{data_topic}': {json.dumps(payload, indent=2)}")
-        
-        # Check if published successfully
-        if result.is_published():
-            logging.info(f"Successfully published temperature-humidity data for {location}")
+        if all_published:
+            logging.info(f"Successfully published all temperature-humidity data for {location}")
             return True
         else:
-            logging.error(f"Failed to publish temperature-humidity data from {host_info['ip']}")
+            logging.error(f"Failed to publish some temperature-humidity data from {host_info['ip']}")
             return False
 
     except ModbusException as e:
@@ -148,40 +162,46 @@ def read_and_publish_cwt_co2(mqtt_client, modbus_client, host_info):
         
         logging.info(f"Processed CWT values from {host_info['ip']} - Humidity: {humidity:.1f}%RH, Temperature: {temperature:.1f}°C, CO2: {co2_ppm}ppm")
         
-        # Prepare new topic structure: Location/{location_name}/{sensor_type}/data
+        # Prepare new topic structure: Location/{location_name}/{type}/...
         location = host_info["location"]
         sensor_type = "CO2-gas"
         current_time = datetime.now(timezone.utc).strftime("%Y-%m-%d %H:%M:%S")
         
-        # Create topic for combined data
-        data_topic = f"Location/{location}/{sensor_type}/data"
+        # Create base topic path
+        base_topic = f"Location/{location}/{sensor_type}"
         
-        # Create JSON payload with all data and status
-        payload = {
-            "timestamp": current_time,
-            "location": location,
-            "sensor_type": sensor_type,
-            "ip": host_info["ip"],
-            "status": "online",
-            "data": {
-                "co2": co2_ppm,
-                "temperature": round(temperature, 1),
-                "humidity": round(humidity, 1)
-            }
-        }
+        # Publish to individual topics
+        topics_data = [
+            (f"{base_topic}/Time", current_time),
+            (f"{base_topic}/Status", "online"),
+            (f"{base_topic}/Data/co2", co2_ppm),
+            (f"{base_topic}/Data/temperature", round(temperature, 1)),
+            (f"{base_topic}/Data/humidity", round(humidity, 1))
+        ]
         
-        # Publish combined data as JSON
-        result = mqtt_client.publish(data_topic, json.dumps(payload))
-        result.wait_for_publish()
+        # Publish all data
+        all_published = True
+        for topic, value in topics_data:
+            try:
+                # Convert value to string for MQTT
+                payload = str(value)
+                result = mqtt_client.publish(topic, payload)
+                result.wait_for_publish()
+                
+                if result.is_published():
+                    logging.info(f"Published to '{topic}': {payload}")
+                else:
+                    logging.error(f"Failed to publish to '{topic}': {payload}")
+                    all_published = False
+            except Exception as e:
+                logging.error(f"Error publishing to '{topic}': {e}")
+                all_published = False
         
-        logging.info(f"Published to '{data_topic}': {json.dumps(payload, indent=2)}")
-        
-        # Check if published successfully
-        if result.is_published():
-            logging.info(f"Successfully published CO2-gas data for {location}")
+        if all_published:
+            logging.info(f"Successfully published all CO2-gas data for {location}")
             return True
         else:
-            logging.error(f"Failed to publish CO2-gas data from {host_info['ip']}")
+            logging.error(f"Failed to publish some CO2-gas data from {host_info['ip']}")
             return False
             
     except ModbusException as e:
@@ -222,6 +242,7 @@ def main_loop():
         # Main loop to read and publish data from all hosts
         while True:
             for host_info in MODBUS_HOSTS:
+                modbus_client = None
                 error_message = None
                 try:
                     modbus_client = ModbusTcpClient(
@@ -246,11 +267,15 @@ def main_loop():
                     sensor_tracker.record_failure(host_info, error_message, mqtt_client)
                     logging.error(f"Error processing {host_info['location']} ({host_info['ip']}): {e}", exc_info=True)
                 finally:
-                    try:
-                        modbus_client.close()
-                        logging.debug(f"Closed connection to {host_info['ip']}")
-                    except:
-                        pass
+                    # Ensure modbus connection is always closed
+                    if modbus_client:
+                        try:
+                            modbus_client.close()
+                            logging.debug(f"Closed connection to {host_info['ip']}")
+                        except Exception as close_error:
+                            logging.warning(f"Error closing connection to {host_info['ip']}: {close_error}")
+                        finally:
+                            modbus_client = None  # Explicit cleanup
                         
                 # Add small delay between processing each sensor
                 time.sleep(1)
@@ -260,6 +285,9 @@ def main_loop():
             logging.info(f"Cycle completed - Online: {summary['online_sensors']}/{summary['total_sensors']} sensors "
                         f"({summary['health_percentage']:.1f}% health), "
                         f"Alerts: {summary['alerted_sensors']}")
+            
+            # Force garbage collection every cycle to prevent memory buildup
+            gc.collect()
                 
             logging.info(f"Waiting {PUBLISH_INTERVAL} seconds until next cycle...")
             time.sleep(PUBLISH_INTERVAL)