From BoardsInterface class (hal.py) method 'mqtt_lib_import_str' has been removed as unnecessary. Improving class MQTTClient2 containing overridden method 'wait_msg' which implements timeout for waiting for broker answer. Example file 1_send_data.py has been changed to avoid adding timeout concerning waiting for broker answer to MESSAGE_RATE.

Author: tomekmalek

1_send_data.py

@@ -21,12 +21,11 @@
 # Main program
 board.network_connect()
 lo.connect()		# Connect to LiveObjects
-last = time.time()
-uptime = time.time()
+last = uptime = time.time()
 
 while True:
-	if time.time() >= last + MESSAGE_RATE:
+	if (time.time()) >= last + MESSAGE_RATE:
 		lo.addToPayload("uptime", int(time.time() - uptime))		# Add value to payload: name - value
 		lo.sendData()												# Sending data to cloud
-		lo.loop() 						# Check for incoming messages and if connection is still active
 		last = time.time()
+		lo.loop() 						# Check for incoming messages and if connection is still active

LiveObjects/Connection.py

@@ -58,14 +58,15 @@ def __init__(self, board, deviceID, port, apiKey, debug=True):
         if self.mode == LiveObjects.BoardsInterface.PYTHON:
             self.__mqtt = paho.Client(deviceID)
         elif self.mode == LiveObjects.BoardsInterface.MICROPYTHON:
-            self.ssl = port == 8883
 
-            class MQTTClient2(MQTTClient):  # overriding original method wait_msg due to infinite waiting
-                def wait_msg(self):
+            class MQTTClient2(MQTTClient):
+                TIMEOUT = 1000  # [ms]
+
+                def wait_msg(self):     # overriding original method wait_msg due to avoid infinite waiting
                     import select
                     poller = select.poll()
                     poller.register(self.sock, select.POLLIN)
-                    res = poller.poll(1000)
+                    res = poller.poll(MQTTClient2.TIMEOUT)
                     if not res:
                         res = None
                     self.sock.setblocking(True)
@@ -98,6 +99,7 @@ def wait_msg(self):
                     elif op & 6 == 4:
                         assert 0
 
+            self.ssl = port == SSL
             self.__mqtt = MQTTClient2(deviceID, self.__server, self.__port, "json+device",
                                       self.__apiKey, 0, self.ssl, {'server_hostname': self.__server})
 
@@ -145,13 +147,12 @@ def __onConnect(self, client="", userdata="", flags="", rc=""):
                 self.__mqtt.subscribe(b"dev/cfg/upd")
                 self.__sendConfig()
 
-
     def connect(self):
         if self.mode == LiveObjects.BoardsInterface.PYTHON:
             self.__mqtt.username_pw_set("json+device", self.__apiKey)
             self.__mqtt.on_connect = self.__onConnect
             self.__mqtt.on_message = self.__onMessage
-            if self.__port == 8883:
+            if self.__port == SSL:
                 filename = "/etc/ssl/certs/ca-certificates.crt"
                 self.__mqtt.tls_set(filename)
             self.__mqtt.connect(self.__server, self.__port, 60)

LiveObjects/hal.py

@@ -39,11 +39,6 @@ def get_lang_str(self):
     def get_lang_id(self):
         return self._lang_id
 
-    def mqtt_lib_import_str(self):
-        import_strings = {BoardsInterface.PYTHON: 'import paho.mqtt.client as paho',
-                          BoardsInterface.MICROPYTHON: 'from umqttrobust import MQTTClient'}
-        return import_strings[self._lang_id]
-
     def get_security_level(self):
         pass
 
@@ -70,7 +65,6 @@ def __init__(self, net_type):
         self._carrier_capability = (BoardsInterface.WIFI, BoardsInterface.LTE)
         self._wifi_tls_capability = True
         self._lte_tls_capability = True
-        self._mqtt_lib = super().mqtt_lib_import_str()
         self._credentials = super().create_credentials(self._net_type)
 
     def network_connect(self):
@@ -93,7 +87,6 @@ def __init__(self, net_type):
         self._net_type = BoardsInterface.WIFI if net_type == BoardsInterface.DEFAULT_CARRIER else net_type
         self._carrier_capability = (BoardsInterface.WIFI,)
         self._wifi_tls_capability = False
-        self._mqtt_lib = super().mqtt_lib_import_str()
         self._credentials = super().create_credentials(self._net_type)
 
     def network_connect(self):
@@ -114,7 +107,6 @@ def __init__(self, net_type):
         self._net_type = BoardsInterface.WIFI if net_type == BoardsInterface.DEFAULT_CARRIER else net_type
         self._carrier_capability = (BoardsInterface.WIFI,)
         self._wifi_tls_capability = True
-        self._mqtt_lib = super().mqtt_lib_import_str()
         self._credentials = super().create_credentials(self._net_type)
 
     def network_connect(self):
@@ -131,7 +123,6 @@ def __init__(self, net_type):
         self._net_type = BoardsInterface.EXISTING_NETWORK if net_type == BoardsInterface.DEFAULT_CARRIER else net_type
         self._carrier_capability = (BoardsInterface.EXISTING_NETWORK,)
         self._existing_network_tls_capability = True
-        self._mqtt_lib = super().mqtt_lib_import_str()
         self._credentials = super().create_credentials(self._net_type)
 
     def network_connect(self):