Role Name: DOCKER

Docker installer for Linux, with control over docker daemon startup. Optionally installs the following packages:

• docker compose
• kubectl
• kubectx ( dependent on kubectl )
• kubens ( installed with kubectx )

Requirements

None.

Role Variables

All of the listed variables are defined in defaults/main.yml. Individual variables can be set or overridden by setting them in a playbook for this role.

• docker_version: ( default: latest )
  • docker version to install
• docker_users: ( default: [] )
  • users to add to docker group
• enable_docker_daemon: ( default: yes )
  • whether to enable and start the docker daemon
  • set to no to run docker as a client
• docker_host: ( default: "" )
  • use in conjuction with enable_docker_daemon to point docker client at a docker host
• install_docker_compose: ( default: yes )
  • install docker compose
• docker_compose_version: ( default: latest )
  • version of docker compose to install
• docker_compose_install_dir: ( default: /usr/local/bin )
  • docker compose install dir
• install_kubectl: ( default: yes )
  • install kubectl
• kubectl_version: ( default: latest )
  • version of kubectl to install
• kubectl_install_dir: ( default: /usr/local/bin )
  • kubectl install dir
• install_kubectx: ( default: yes )
  • install kubectx and kubens
• kubectx_version: ( default: latest )
  • version of kubectx and kubens to install
• kubectx_install_path: ( default : /usr/local/bin/kubectx )
  • kubectx and kubens install path

Dependencies

None.

Example Playbook

Example below for the following:

• Installation of specific versions of docker, docker compose and kubectl
• Installation of docker as a client pointing to a specific docker host
• Addition of the root user to the docker group

- hosts: servers
  roles:
      - deluxebrain.docker
        docker_version: 5:19.03.5*
        enable_docker_daemon: no
        docker_host: "tcp://localhost:2375"
        docker_users:
          - root
        compose_version: 1.25.2
        kubectl_version: 1.17.2

Development Installation

The included files, requirements-dev.txt and requirements.txt install development and production dependencies accordingly.

The included Makefile includes several targets related to the installation of the development environment and the management of the development process.

Packages are managed through the pip-tools suite. This, and other development requirements, are installed through the requirements-dev.txt file.

# Create project virtual environment
# Install development dependencies into virtual environment
make install

pip-tools manages the project dependencies through the included requirements.in file, and is responsible both for the generation of the requirements.txt file and package installion into the virtual environment.

Note that this means that the requirements.txt file should not be manually edited and must be regenerated every time the requirements.in file is changed.

# Compile the requirements.in file to requirements.txt
# Install the requirements.txt pacakges into the virtual environment
make sync

Notes

Docker and apt

Docker is installed using the docker-ce apt package. The following apt command can be used to list all available versions:

apt-cache madison docker-ce

Docker and /etc/profile

The path for kubectx is setup in /etc/profile. Docker by default connects to containers using an interactive non-login shell, and hence by default /etc/profile and hence the path for kubectx will not be set.

The following demonstrates the use of kubectx with docker:

docker ps
$ instance

docker exec -it instance bash --login
$ root@instance:/#

License

MIT / BSD

Author Information

This role was created in 2020 by deluxebrain.