MQTT2Docker

Bash scripts to perform simple Docker container management through MQTT, and send container events to MQTT.

Scripts

• mqtt2docker subscribes to MQTT and performs simple operations (like Start, Stop) on containers
• docker2mqtt subscribes to Docker events API and publishes them on MQTT

mqtt2docker

Publish messages to mqtt/<containerName>/cmd to send commands to a container.

Example: START a container named portainer: send a message to the topic mqtt/portainer/cmd with the payload start (payload is not case-sensitive)

Commands (payloads) available

• START
• STOP
• RESTART
• PAUSE
• UNPAUSE
• KILL

docker2mqtt

The script will publish all events occurring on a container to mqtt/<containerName>/stat.

Example: when a container named portainer starts: a message to the topic mqtt/portainer/stat is published with the payload start.

Env variables

Use environment variables as configurations:

• MQTT_HOST: host where the MQTT broker is running (if not specified: localhost)
• MQTT_UID: UID of the user that will run the mosquitto_sub/mosquitto_pub commands (if not specified: 1000)

sudo bash MQTT_HOST=127.0.0.1 MQTT_UID=1000 mqtt2docker.sh

Premises

• Scripts read or write on the Docker API socket (/var/run/docker.sock), so they must run as root
• Scripts are written in pure Bash, but require mosquitto-client (MQTT client) and jq (JSON parser) packages
• Calls to mosquitto_pub and mosquitto_sub are performed by another user different than root
• Both scripts can run on Docker containers mapping the /var/run/docker.sock as a bind volume

TODO

• Create Docker images
• (More) Setting customization - or pass arguments to the script to be part of the mosquitto_sub/mosquitto_pub args
• Add binary pub/sub endpoints (ON/OFF - like payloads)

Changelog

• 0.1 - Initial release