From 7562b4164b0d79f233f6bc967a03ad582ef7b03b Mon Sep 17 00:00:00 2001
From: Martin Hjelmare <marhje52@kth.se>
Date: Mon, 14 May 2018 22:52:44 +0200
Subject: [PATCH] Fix key error upon missing node (#14460)

* This is needed after gateway ready message generates an update while
  persistence is off, or while the gateway node hasn't been presented
  yet.
---
 homeassistant/components/mysensors.py | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/homeassistant/components/mysensors.py b/homeassistant/components/mysensors.py
index f5ad59095dc..6721669a026 100644
--- a/homeassistant/components/mysensors.py
+++ b/homeassistant/components/mysensors.py
@@ -495,8 +495,9 @@ def gw_callback_factory(hass):
         _LOGGER.debug(
             "Node update: node %s child %s", msg.node_id, msg.child_id)
 
-        child = msg.gateway.sensors[msg.node_id].children.get(msg.child_id)
-        if child is None:
+        try:
+            child = msg.gateway.sensors[msg.node_id].children[msg.child_id]
+        except KeyError:
             _LOGGER.debug("Not a child update for node %s", msg.node_id)
             return