OpenUV: Fix update by skipping when protection window is null (home-assistant#154487)

Author: wbyoung

homeassistant/components/openuv/coordinator.py

@@ -68,18 +68,26 @@ async def _async_update_data(self) -> dict[str, Any]:
 
 
 class OpenUvProtectionWindowCoordinator(OpenUvCoordinator):
-    """Define an OpenUV data coordinator for the protetction window."""
+    """Define an OpenUV data coordinator for the protection window."""
 
     _reprocess_listener: CALLBACK_TYPE | None = None
 
     async def _async_update_data(self) -> dict[str, Any]:
         data = await super()._async_update_data()
 
         for key in ("from_time", "to_time", "from_uv", "to_uv"):
-            if not data.get(key):
-                msg = "Skipping update due to missing data: {key}"
+            # a key missing from the data is an error.
+            if key not in data:
+                msg = f"Update failed due to missing data: {key}"
                 raise UpdateFailed(msg)
 
+            # check for null or zero value in the data & skip further processing
+            # of this update if one is found. this is a normal condition
+            # indicating that there is no protection window.
+            if not data[key]:
+                LOGGER.warning("Skipping update due to missing data: %s", key)
+                return {}
+
         data = self._parse_data(data)
         data = self._process_data(data)