Add support for contact sensor (T110) (#877)

Initial support for T110 contact sensor & T110 fixture by courtesy of @ngaertner.

kasa/smart/modules/__init__.py

@@ -8,6 +8,7 @@ from .childdevicemodule import ChildDeviceModule
 from .cloudmodule import CloudModule
 from .colormodule import ColorModule
 from .colortemp import ColorTemperatureModule
+from .contact import ContactSensor
 from .devicemodule import DeviceModule
 from .energymodule import EnergyModule
 from .fanmodule import FanModule
@@ -45,5 +46,6 @@ __all__ = [
     "ColorTemperatureModule",
     "ColorModule",
     "WaterleakSensor",
+    "ContactSensor",
     "FrostProtectionModule",
 ]

kasa/smart/modules/contact.py

@@ -0,0 +1,42 @@
+"""Implementation of contact sensor module."""
+
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+from ...feature import Feature
+from ..smartmodule import SmartModule
+
+if TYPE_CHECKING:
+    from ..smartdevice import SmartDevice
+
+
+class ContactSensor(SmartModule):
+    """Implementation of contact sensor module."""
+
+    REQUIRED_COMPONENT = None  # we depend on availability of key
+    REQUIRED_KEY_ON_PARENT = "open"
+
+    def __init__(self, device: SmartDevice, module: str):
+        super().__init__(device, module)
+        self._add_feature(
+            Feature(
+                device,
+                id="is_open",
+                name="Open",
+                container=self,
+                attribute_getter="is_open",
+                icon="mdi:door",
+                category=Feature.Category.Primary,
+                type=Feature.Type.BinarySensor,
+            )
+        )
+
+    def query(self) -> dict:
+        """Query to execute during the update cycle."""
+        return {}
+
+    @property
+    def is_open(self):
+        """Return True if the contact sensor is open."""
+        return self._device.sys_info["open"]