About this project

This is a project for capturing BLE data from a Xiaomi Mijia 2
hygrometer-thermometer and publishing it. The repository includes:

• A service to connect to a number of Mijia sensors over BLE and publish their readings to an MQTT broker following the Homie convention.
• A service to discover devices on an MQTT broker following the Homie convention and record their property value changes to an InfluxDB database.
• A library for implementing Homie devices.
• A library for implementing Homie controllers.
• A library for reading Mijia sensors.
• Generated bindings for talking to BlueZ on Linux.

The project originated from a
blog post,
and some ideas came from a
Python utility for talking to the same sensors,
especially this issue thread.

If you want a bit more back-story, there is also a slide deck.

License

Licensed under either of

• Apache License, Version 2.0
  (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license
  (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
dual licensed as above, without any additional terms or conditions.

Setup

To run this code on your Raspberry Pi, you will need:

• Some Xiaomi Mijia version 2 Bluetooth temperature and humidity sensors.
• A working Rust toolchain and Docker on your laptop.
• An MQTT broker to connect to (test.mosquitto.org works okay for testing, but you will want to deploy your own if you're monitoring your house).
• Something to read the measurements from MQTT. Homie Device Discovery is probably easiest for debugging.

After following these steps, you should end up with something that looks like this:

• Start by finding out which sensors you have:

  TARGET_SSH=pi@raspberrypi.local EXAMPLE=list-sensors ./run.sh
  

• Add each of the sensors to /home/pi/sensor_names.conf on the Raspberry Pi. Each line should be of the form:

  A4:C1:38:D7:21:17=Landing
  

  If you don't know the sensor names yet, just make some names up for now.

• You will also want to copy mijia-homie/.env.example to /home/pi/.env and edit it to suit your needs.

• You should then be able to run the publisher using run.sh with default arguments:

  TARGET_SSH=pi@raspberrypi.local ./run.sh
  

  This will start the publisher under systemd and show you the logs.

• It takes a while to connect to all of the sensors and start getting readings. Once everything is running, you can use HoDD to see your readings.

• If everything is visible in HoDD then you can add other integrations. Anything that understands Homie should be able to read your sensors. OpenHAB is what we're using, but take a look at the Homie Implementations page and see if anything inspires you.