Home Assistant Git Exporter

config/custom_components/versatile_thermostat/keep_alive.py

@@ -0,0 +1,63 @@
+"""Building blocks for the heater switch keep-alive feature.
+
+The heater switch keep-alive feature consists of regularly refreshing the state
+of directly controlled switches at a configurable interval (regularly turning the
+switch 'on' or 'off' again even if it is already turned 'on' or 'off'), just like
+the keep_alive setting of Home Assistant's Generic Thermostat integration:
+ https://www.home-assistant.io/integrations/generic_thermostat/
+"""
+
+import logging
+from collections.abc import Awaitable, Callable
+from datetime import timedelta, datetime
+
+from homeassistant.core import HomeAssistant, CALLBACK_TYPE
+from homeassistant.helpers.event import async_track_time_interval
+
+
+_LOGGER = logging.getLogger(__name__)
+
+
+class IntervalCaller:
+    """Repeatedly call a given async action function at a given regular interval.
+
+    Convenience wrapper around Home Assistant's `async_track_time_interval` function.
+    """
+
+    def __init__(self, hass: HomeAssistant, interval_sec: float) -> None:
+        self._hass = hass
+        self._interval_sec = interval_sec
+        self._remove_handle: CALLBACK_TYPE | None = None
+
+    @property
+    def interval_sec(self) -> float:
+        """Return the calling interval in seconds."""
+        return self._interval_sec
+
+    def cancel(self):
+        """Cancel the regular calls to the action function."""
+        if self._remove_handle:
+            self._remove_handle()
+            self._remove_handle = None
+
+    def set_async_action(self, action: Callable[[], Awaitable[None]]):
+        """Set the async action function to be called at regular intervals."""
+        if not self._interval_sec:
+            return
+        self.cancel()
+
+        async def callback(_time: datetime):
+            try:
+                _LOGGER.debug(
+                    "Calling keep-alive action '%s' (%ss interval)",
+                    action.__name__,
+                    self._interval_sec,
+                )
+                await action()
+            except Exception as e:  # pylint: disable=broad-exception-caught
+                _LOGGER.error(e)
+                self.cancel()
+
+        self._remove_handle = async_track_time_interval(
+            self._hass, callback, timedelta(seconds=self._interval_sec)
+        )