Inheritance with App classes in Appdaemon

I’ve just started to organize my automations through appdaemon, so I’m still learning. My initial plan was to simplify repeated scenarios, like power saving lights (turns off after x min) and motions detection.

I’ve created a PowersavingLight class that works well. It just uses a countdown timer to turn the lights off when the timer reaches 0. The timer is controlled by input_number entities in the UI and a cleaning mode switch that disables the timer. I was hoping to build off that functionality for certain lights that should respond to motion. The idea was to create a new class, MotionLight, that inherits the PowersavingLight class but I seem to be running into an error.

FYI, my python is quite rusty, but I thought the inheritance process works as follows.

import hassapi as hass
import globals
import os
import datetime

class PowersavingLight(hass.Hass):

    TIMER_PERIOD_S            = 5  # SECONDS
    SEC_PER_MIN               = 60

    def initialize(self):

        self.description = "EMPTY"
        self.duration = self.DEFAULT_TIMER_DURATION_M
        self.duration_id = None
        self.timer_handle = None
        self.time_remaining = None
        self.light = None
        self.cleaning_mode = "off"


import hassapi as hass
import globals
import powersaving_lights

# Motion activate lights.  Extends Power Saving lights

class MotionLight(PowersavingLight):

    def initialize(self):
        if "motion_sensor" in self.args:
            self.motion_sensor = self.args["motion_sensor"]

Here’s the error

2020-11-10 09:34:12.683826 INFO AppDaemon: Reloading Module: /conf/apps/
2020-11-10 09:34:12.683920 INFO AppDaemon: Loading App Module: motion_lights
2020-11-10 09:34:12.685086 INFO AppDaemon: Initializing app motion_lights using class MotionLight from module motion_lights
2020-11-10 09:34:12.686218 WARNING motion_lights: ------------------------------------------------------------
2020-11-10 09:34:12.686494 WARNING motion_lights: Unexpected error initializing app: motion_lights:
2020-11-10 09:34:12.686730 WARNING motion_lights: ------------------------------------------------------------
2020-11-10 09:34:12.687046 WARNING motion_lights: Traceback (most recent call last):
  File "/usr/local/lib/python3.8/site-packages/appdaemon/", line 907, in check_app_updates
    await self.init_object(app)
  File "/usr/local/lib/python3.8/site-packages/appdaemon/", line 294, in init_object
    "object": app_class(
TypeError: MotionLight() takes no arguments

What am I missing?

Hi @amclean1980,

You need to import the class PowersavingLight like:

from powersaving_lights import PowersavingLight

Also, you probably want to call the initialize from the parent class, ao in the MotionLight in the initialize function, you will need to do:


Let me know if this works, I am happy to help further if needed :slight_smile:

Xavi M.

ha, thanks. I was just reading about imports and realized my error. I was just about to delete the post because it’s pretty basic Python that I forgot.

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