powermeter: catch invalid values for power and energy

pyfritzhome/devicetypes/fritzhomedevicepowermeter.py

@@ -34,8 +34,17 @@ def has_powermeter(self):
     def _update_powermeter_from_node(self, node):
         _LOGGER.debug("update powermeter device")
         val = node.find("powermeter")
-        self.power = int(val.findtext("power"))
-        self.energy = int(val.findtext("energy"))
+
+        try:
+            self.power = int(val.findtext("power"))
+        except Exception:
+            pass
+
+        try:
+            self.energy = int(val.findtext("energy"))
+        except Exception:
+            pass
+
         try:
             self.voltage = int(val.findtext("voltage"))
         except Exception:

tests/responses/powermeter/device_list_faulty.xml

@@ -10,13 +10,10 @@
             <devicelock>0</devicelock>
         </switch>
         <powermeter>
-            <power>0</power>
-            <energy>0</energy>
-            <voltage>0</voltage>
         </powermeter>
         <temperature>
             <celsius>285</celsius>
             <offset>0</offset>
         </temperature>
     </device>
-</devicelist>
+</devicelist>

tests/test_fritzhomedevicepowermeter.py

@@ -74,7 +74,7 @@ def test_faulty_powermeter_properties(self):
         self.fritz.update_devices()
         device = self.fritz.get_device_by_ain("08761 0000434")
 
-        assert device.energy == 0
-        assert device.power == 0
-        assert device.voltage == 0
+        assert device.energy is None
+        assert device.power is None
+        assert device.voltage is None
         assert device.current is None