change broker, introduce mqtt authentication

config.py

@@ -1,5 +1,11 @@
-ssid = 'telemetry'
+import secrets
 
-mqtt_server = '172.16.10.47'
-heartbeat_topic = b'IoT/rpipwThermometer/0/Heartbeat'
-watchdog_topic = b'IoT/Watchdog'
+SSID = 'telemetry'
+WPA_KEY = secrets.WPA_KEY
+MQTT_SERVER = '172.16.10.47'
+MQTT_LOGIN = 'thermo-anna'
+MQTT_PASSWORD = secrets.MQTT_PASSWORD
+HEARTBEAT_TOPIC = b'IoT/rpipwThermometer/0/Heartbeat'
+WATCHDOG_TOPIC = b'IoT/Watchdog'
+
+MAX_CONNECT_RETRY_CNT = 1000000

main.py

@@ -1,13 +1,12 @@
 # main.py -- put your code here!
 
-from umqttsimple import MQTTClient
+from umqttsimple import MQTTClient, MQTTException
 import time
 import ubinascii
 from machine import WDT
 import network
 import os
 import config
-import secrets
 
 last_message = 0
 message_interval = 5
@@ -20,20 +19,26 @@ client = None
 def init():
     wlan = network.WLAN(network.STA_IF)
     wlan.active(True)
-    wlan.connect(config.ssid, secrets.wpakey)
+    wlan.connect(config.SSID, config.WPA_KEY)
 
-    while (not wlan.isconnected()):
-        print('Not yet connected to WLAN')
+    connectCnt = 0
+    while (not wlan.isconnected() or connectCnt > config.MAX_CONNECT_RETRY_CNT):
+        connectCnt += 1
+    if (not wlan.isconnected()):
+        print("Failed to connect to wlan, restarting")
+        machine.reset()
 
     print('Connected to WLAN')
 
     global client
     clientId = ubinascii.hexlify(bytearray(os.urandom(16))).decode()
-    client = MQTTClient(clientId, config.mqtt_server, keepalive=60, ssl=True)
+    client = MQTTClient(clientId, config.MQTT_SERVER, keepalive=60, 
+        ssl=True, user=config.MQTT_LOGIN, password=config.MQTT_PASSWORD)
     client.set_callback(mqtt_callback)
     client.connect()
-    client.subscribe(config.watchdog_topic)
-    print(f"Connected to {config.mqtt_server} MQTT Broker")
+    print(f"Connected to MQTT broker {config.MQTT_SERVER} ")
+    client.subscribe(config.WATCHDOG_TOPIC)
+    print(f"Subscribed to {config.WATCHDOG_TOPIC}")
 
     global wdt
     wdt = WDT(timeout=5000)
@@ -44,7 +49,7 @@ def init():
 def mqtt_callback(topic, msg):
     global wdt, wdtCnt
     print(f"Received: {topic}: {msg}")
-    if topic == config.watchdog_topic:
+    if topic == config.WATCHDOG_TOPIC:
         wdtCnt += 1
         print(f"feed watchdog {wdtCnt}")
         wdt.feed()
@@ -57,7 +62,7 @@ def main():
     try:
         init()
     except Exception as e:
-        print(f"Some error when starting: {e}")
+        print(f"Some error when starting: {e.__class__.__name__}, {e}")
         time.sleep(15)
         machine.reset()