Docker Support for LittleBrother

Overview

There is a docker image available to run a LittleBrother slave process. The easiest way to use it start as follows:

• Download the docker-compose.yml file from GitHub and store in a local directory. Alternatively, clone this repository by issuing

  git clone https://github.com/marcus67/docker-little-brother.git    
  

• Copy the template.env and save it as .env into the same directory.

• Read the following short sections to choose the right version of the image and acknowledge the security aspects.

• Continue with Section Running the Slave.

Tag Naming Conventions

The tag names of the images are derived from the pattern BRANCH-REVISION where BRANCH is either master or release and REVISION represents the number as listed in changes. The special tag latest is used for the most up-to-date release revision.

Security Details

• In order for LittleBrother to be able to kill processes, the configuration contains the option pid: host. This makes sure that the container sees ALL processes including those running outside the container.

• For the same reason the container has to be run in a privileged mode (using privileged:true). Ideally, this should be replaced by activating a set of Linux capabilities. For details see this issue.

• In order to be able to "speak" (that is play sound files), the process inside the container has to access the sound device of the host. This is made possible by mounting the file /etc/asound.conf and the device /dev/snd into the container. Note: This requirement is obsolete since notifications should be issued by LittleBrotherTaskbar now and no longer by the slave process.

Running the Container

Running the Regular Slave

• Edit the environment variables in the .env file. See the comments in the file.

• Open a shell in the directory containing docker-compose.yml.

• Start the container by issuing in the shell

  docker-compose up -d slave 
  

Running the Legacy Slave

The legacy slave can be used to enable notifications and audio playback using the application. However, this is not recommended. Please, consider installing LittleBrotherTaskbar instead.

The steps are the same as with the regular slave (see above) except for issuing

    docker-compose up -d legacy-slave