Fix compatibility issues with old FW that doesn't support LWT

Author: epdevlab

inelsmqtt/devices/__init__.py

@@ -140,8 +140,9 @@ def is_available(self) -> bool:
             bool: True/False
         """
         gw = self.__mqtt.messages().get(self._Device__gw_connected_topic)
-        if not GW_CONNECTED.get(gw):
-            return False
+        if gw is not None:
+            if not GW_CONNECTED.get(gw):
+                return False
 
         val = self.__mqtt.messages().get(self._Device__connected_topic)
         if isinstance(val, (bytes, bytearray)):

setup.py

@@ -3,7 +3,7 @@
 
 setup(
     name="elkoep-mqtt",
-    version="0.2.27",
+    version="0.2.28",
     url="https://github.com/epdevlab/elkoep-mqtt",
     license="MIT",
     author="Elko EP s.r.o.",