mafrosis / w1therm

Publish w1 type sensor readings on MQTT with Home Assistant autodiscovery

W1therm for Rpi and Home Assistant

A simple python app running in docker for reading w1 type sensors (such as DS1822, DS18S20 & DS18B20), and publish via MQTT. Autodiscovery for Home Assistant is baked in.

Building

The default base image is balenalib/raspberrypi3-python, which is suitable for raspberrypi3/4:

docker-compose build

Or, specify a different base image, for example a raspberrypi zero:

docker-compose build --build-arg BASE_IMAGE=balenalib/raspberry-pi-python

Running

You are required to specify at least two environment variables. Export these in your shell before running the docker-compose up command.

In the simplest configuration, an MQTT broker and an MQTT topic are required:

• MQTT_HOST=<hostname or IP>
• MQTT_TOPIC_ROOM=kitchen

And in Home Assistant autodiscovery mode:

• MQTT_HOST=<hostname or IP>
• HA_DEVICE=rpi4
• HA_SENSOR_NAME='Living Room'

HA DEVICE is required in Home Assistant to group the sensors against a device.

HA_SENSOR_NAME is the friendly name shown in the Home Assistant UI.

NOTE: in this configuration the MQTT topic is derived from the HA_SENSOR_NAME setting.

And to start the app:

docker-compose up

Debug

Setting the DEBUG environment var will cause sensor readings to be published to the docker logs.

Additionally ipdb is installed if you want to debug the python code.

MQTT Topic

The temperature/humidity messages are published on:

• home/<MQTT_TOPIC_ROOM>/temperature
• home/<MQTT_TOPIC_ROOM>/humidity