Base Device

SmartDevice class

The basic functionalities of all supported devices are accessible using the common SmartDevice base class.

The property accesses use the data obtained before by awaiting SmartDevice.update(). The values are cached until the next update call. In practice this means that property accesses do no I/O and are dependent, while I/O producing methods need to be awaited. See Update Cycle for more detailed information.

Note

The device instances share the communication socket in background to optimize I/O accesses. This means that you need to use the same event loop for subsequent requests. The library gives a warning (“Detected protocol reuse between different event loop”) to hint if you are accessing the device incorrectly.

Methods changing the state of the device do not invalidate the cache (i.e., there is no implicit SmartDevice.update() call made by the library). You can assume that the operation has succeeded if no exception is raised. These methods will return the device response, which can be useful for some use cases.

Errors are raised as SmartDeviceException instances for the library user to handle.

Simple example script showing some functionality:

import asyncio
from kasa import SmartPlug

async def main():
    p = SmartPlug("127.0.0.1")

    await p.update()  # Request the update
    print(p.alias)  # Print out the alias
    print(p.emeter_realtime)  # Print out current emeter status

    await p.turn_off()  # Turn the device off

if __name__ == "__main__":
    asyncio.run(main())

If you want to perform updates in a loop, you need to make sure that the device accesses are done in the same event loop:

import asyncio
from kasa import SmartPlug

async def main():
    dev = SmartPlug("127.0.0.1")  # We create the instance inside the main loop
    while True:
        await dev.update()  # Request an update
        print(dev.emeter_realtime)
        await asyncio.sleep(0.5)  # Sleep some time between updates

if __name__ == "__main__":
    asyncio.run(main())

Refer to device type specific classes for more examples: SmartPlug, SmartBulb, SmartStrip, SmartDimmer, SmartLightStrip.

Energy Consumption and Usage Statistics

Note

In order to use the helper methods to calculate the statistics correctly, your devices need to have correct time set. The devices use NTP and public servers from NTP Pool Project to synchronize their time.

Energy Consumption

The availability of energy consumption sensors depend on the device. While most of the bulbs support it, only specific switches (e.g., HS110) or strips (e.g., HS300) support it. You can use has_emeter to check for the availability.

Usage statistics

You can use on_since to query for the time the device has been turned on. Some devices also support reporting the usage statistics on daily or monthly basis. You can access this information using through the usage module (kasa.modules.Usage):

dev = SmartPlug("127.0.0.1")
usage = dev.modules["usage"]
print(f"Minutes on this month: {usage.usage_this_month}")
print(f"Minutes on today: {usage.usage_today}")

API documentation