systemctl-mqtt

systemctl-mqtt

MQTT client triggering & reporting shutdown on systemd-based systems

Setup

$ pip3 install --user --upgrade systemctl-mqtt
$ systemctl-mqtt --mqtt-host HOSTNAME_OR_IP_ADDRESS

On debian-based systems, a subset of dependencies can optionally be installed via:

$ sudo apt-get install --no-install-recommends python3-jeepney python3-paho-mqtt

Usage

Schedule Poweroff

Schedule poweroff by sending a MQTT message to topic systemctl/hostname/poweroff.

$ mosquitto_pub -h MQTT_BROKER -t systemctl/hostname/poweroff -n

Shutdown Report

systemctl-mqtt subscribes to logind's PrepareForShutdown signal.

systemctl halt|poweroff|reboot triggers a message with payload true on topic systemctl/hostname/preparing-for-shutdown.

Lock Screen

Lock screen by sending a MQTT message to topic systemctl/hostname/lock-all-sessions.

$ mosquitto_pub -h MQTT_BROKER -t systemctl/hostname/lock-all-sessions -n

Suspend

$ mosquitto_pub -h MQTT_BROKER -t systemctl/hostname/suspend -n

Monitor ActiveState of System Units

$ mosquitto_pub --monitor-system-unit foo.service \
    --monitor-system-unit bar.service …

enables reports on topic systemctl/[hostname]/unit/system/[unit_name]/active-state.

Home Assistant 🏡

Automatic Discovery

When MQTT Discovery is enabled (default in Home Assistant ≥0.117.0), the following entities will be added automatically:

• binary_sensor.[hostname]_logind_preparing_for_shutdown
• button.[hostname]_logind_lock_all_sessions
• button.[hostname]_logind_poweroff
• button.[hostname]_logind_suspend
• sensor.[hostname]_unit_system_[unit_name]_active_state for --monitor-system-unit [unit_name]

Pass --homeassistant-discovery-prefix custom-prefix to systemctl-mqtt when using a custom discovery topic prefix.

Manual YAML Configuration

Send Poweroff Command

# https://www.home-assistant.io/docs/mqtt/broker/#configuration-variables
mqtt:
  broker: BROKER_HOSTNAME_OR_IP_ADDRESS
  # credentials, additional options…

script:
  poweroff_raspberry_pi:
    sequence:
      service: mqtt.publish
      data:
        topic: systemctl/raspberrypi/poweroff

homeassistant:
  customize:
    script.poweroff_raspberry_pi:
      friendly_name: poweroff pi
      icon: mdi:power

Trigger Automation on Shutdown

automation:
- trigger:
    platform: mqtt
    topic: systemctl/raspberrypi/preparing-for-shutdown
    payload: 'true'
  action:
    service: switch.turn_off
    entity_id: switch.desk_lamp

Docker 🐳

1. Clone this repository.
2. Edit docker-compose.yml.
3. Load AppArmor profile: sudo apparmor_parser ./docker-apparmor-profile
4. sudo docker-compose up --build

Pre-built docker image are available at https://hub.docker.com/r/fphammerle/systemctl-mqtt/tags

Annotation of signed tags docker/* contains docker image digests: https://github.com/fphammerle/systemctl-mqtt/tags

MQTT via TLS

TLS is enabled by default. Run systemctl-mqtt --mqtt-disable-tls … to disable TLS.

MQTT Authentication

systemctl-mqtt --mqtt-username me --mqtt-password-file /run/secrets/password …
# or for testing (unsafe):
systemctl-mqtt --mqtt-username me --mqtt-password secret …

Adapt Poweroff Delay

systemctl-mqtt --poweroff-delay-seconds 60 …