docker-openluup

A Dockerfile and Composefile for creation of a Debian or Alpine based openluup container.

OpenLuup is a pure Lua open-source emulation of the Vera Luup environment. This image provides a runtime environment and includes all Vera Lua libraries. In addition, a CoAP library for Lua, luacoap is included.

The Dockerized openluup environment is based on the openLuup installation script and starts with a running OpenLuup instance on port 3480 using a modified version of the openluup_reload script. This modified script adds a hook that captures the stop signal send to the container and calls the luup stop API call to gracefully shutdown a container.

The docker image of openLuup is available from Docker Hub as vwout/openluup and comes in two flavors: based on Debian (tagged 'slim') and based on Alpine (tagged 'alpine'). This image contains the master branch code of openLuup.

Base image	Label	Layers	Vcs Revision
Debian 10 'Buster' (slim)
Alpine 3.11

Running

To start openLuup, invoke docker and add options like volume mounts (see below) to your liking:

docker run -p 3480:3480 vwout/openluup

When a container is started in this manner, the configuration and plugins are stored with the container. This means that when the container is removed, the configuration is also lost.

The docker-compose.yml file in the repository defines the openLuup image in two variants (using the master and development branch of openLuup), for both a debian and alpine based image and contains a definition for mapping ports, binding a local directory for plugin development and mounting named volumes.

docker-compose up openluup-development

Configuration

The image runs openLuup with AltUI out of the box. Confguration is easiest via AltUI, which is available on http://localhost:3480/, which redirects to http://localhost:3480/data_request?id=lr_ALTUI_Handler&command=home#. Additionally, openLuup provides a console interface for easy operational access at http://localhost:3480/console.

OpenLuup is installed in /etc/cmh-ludl/. This folder and the folders /etc/cmh-ludl/backup/ and /etc/cmh-lu are shared as volumes to store user files or retrieve backups of the user_data JSON file.

Environment

• USER_DATA_JSON: To provide a custom user_data.json file, mount it as /etc/cmh-ludl/user_data.json, or set the path to an alternative user_data JSON file using the environment variable USER_DATA_JSON. Setting the environment variable will load the provided userdata. openLuup will not update the userdata to the file. The json is only used during startup. To obtain the configuration, use user_data.json from /etc/cmh-ludl/, or pick a backup from /etc/cmh-ludl/backup/.
• TZ: The timezone used in the container can be set using the TZ environment variable. The image defaults to UTC. Both timezone names (e.g. 'Europe/Amsterdam') and UTC offsets (e.g. 'GMT+2').

Persisting configuration

To keep the openLuup configuration and plugin data even when removing the openLuup container, use volumes. The following docker-compose.yml defines a volume that will contain the configuration and plugin files:

version: '2.3'

services:
  openluup:
    image: vwout/openluup:alpine
    ports:
      - "3480:3480"
    restart: unless-stopped
    volumes:
      - type: volume
        source: cmh-ludl
        target: /etc/cmh-ludl/

volumes:
  cmh-ludl:
    name: openluup-env
    labels:
      org.label-schema.description: "openLuup environment with plugins and userdata"

For easiest operation during development, use the docker-compose.yml file in the repository. It creates 3 named volumes (openluup-env, openluup-logs, openluup-backups) and contain the openLuup environment, logs and backups respectively.

You can also do this manually. Start by creating docker volumes:

docker volume create openluup-env
docker volume create openluup-logs
docker volume create openluup-backups

Create an openLuup container, e.g. based on Alpine linux and mount the created (still empty) volumes:

docker run -d \
       -v openluup-env:/etc/cmh-ludl/ \
       -v openluup-logs:/etc/cmh-ludl/logs/ \
       -v openluup-backups:/etc/cmh-ludl/backup/ \
       -p 3480:3480
       vwout/openluup:alpine

Any configuration change that you apply on openLuup or AltUI, like installing and configuring plugins, will be saved on the openluup-env volume. This volume will not be removed when the container stops or the image is removed. The data is only deleted upon a docker volume rm action.

Credits

Credits for the alpine based lua (and luarocks) image go to Andriy Kornatskyy for his docker-library for lua. The alpine image for openLuup is using alpine directly instead of using akorn/luarocks because that lua-alpine base image is compiled for posix instead of linux, which prevents the usage of modules installed via luarocks, and also for size optimization reasons.