Only consider timestamps larger than 1 as a valid timestamp

custom_components/knmi/binary_sensor.py

@@ -31,7 +31,7 @@
             "description": coordinator.get_value(["liveweer", 0, "ltekst"]),
             "code": coordinator.get_value(["liveweer", 0, "wrschklr"]),
             "next_code": coordinator.get_value(["liveweer", 0, "wrsch_gc"]),
-            "timestamp": coordinator.get_value_datetime(["liveweer", 0, "wrsch_gts"]),
+            "timestamp": coordinator.get_value_datetime(["liveweer", 0, "wrsch_gts"], "-"),
         },
     ),
     KnmiSensorDescription(

custom_components/knmi/coordinator.py

@@ -73,7 +73,9 @@ def get_value(self, path: list[int | str], default=None) -> Any:
             _LOGGER.warning("Can't find a value for %s in the API response", path)
             return default
 
-    def get_value_datetime(self, path: list[int | str], default=None) -> datetime:
+    def get_value_datetime(
+        self, path: list[int | str], default=None
+    ) -> datetime | None:
         """
         Get a datetime value from the data by a given path.
         When the value is absent, the default (None) will be returned and an error will be logged.
@@ -83,8 +85,11 @@ def get_value_datetime(self, path: list[int | str], default=None) -> datetime:
 
         # Timestamp.
         if isinstance(value, int):
-            _LOGGER.debug("convert %s to datetime (from timestamp)", value)
-            return datetime.fromtimestamp(value, tz=timezone)
+            if value > 0:
+                _LOGGER.debug("convert %s to datetime (from timestamp)", value)
+                return datetime.fromtimestamp(value, tz=timezone)
+
+            return default
 
         # Time.
         if re.match(r"^\d{2}:\d{2}$", value):

tests/test_coordinator.py

@@ -74,7 +74,7 @@ async def test_get_value_datetime(hass: HomeAssistant, mocked_data, caplog):
 
     coordinator: KnmiDataUpdateCoordinator = hass.data[DOMAIN][config_entry.entry_id]
 
-    # Timestamp
+    # Timestamp.
     assert (
         str(coordinator.get_value_datetime(["liveweer", 0, "timestamp"]))
         == "2024-02-14 22:08:03+01:00"
@@ -84,6 +84,10 @@ async def test_get_value_datetime(hass: HomeAssistant, mocked_data, caplog):
         == "2024-02-14 23:00:00+01:00"
     )
 
+    # Timestamp, 0 or lower value.
+    coordinator.data["liveweer"][0]["wrsch_gts"] = 0
+    assert coordinator.get_value_datetime(["liveweer", 0, "wrsch_gts"]) is None
+
     # Time.
     assert (
         str(coordinator.get_value_datetime(["liveweer", 0, "sup"]))