Generic docker systemd service deploy

Creates a systemd unit file that manages a docker image.

Requirements

• Pip installed on host
• Docker installed on the host
• python-mysqldb if you use the mariadb or postgres db type.
• pymongo if you use the mongo db type.
• A directory for the database data owned by the user with gid and uid 1000. Specify it in the variable docker_service_directory_db.

Role Variables

• enable_db: Boolean to enable database container deployment.
• enable_redis: Boolean to enable Redis container deployment.
• create_user_and_db: Boolean to enable the creation of a DB and a user. Only works with mariadb and mongo database backends.
• create_network: Boolean to enable docker network creation for the service and the DB.
• docker_service_prefix: Prefix for the in-docker services. This is useful to be able to restart all of them with one command: systemctl restart docker.*
• service_name: Name of the systemd service.
• method: pull or build to get the docker image.
• service_pre_command: Command to run before the docker_command one. Pull or build generally. Add - at the beginning of the command if you don't want the service start up to fail if this command fails.
• service_db_name: Name of the systemd DB service.
• docker_network_name: Name of the docker network for the service and DB.
• docker_image: Name of the docker image to launch as a service.
• docker_db_image: Name of the docker image to launch as the service's DB. Use the debian based one for postgres.
• docker_redis_image: Name of the docker image to launch as the service's Redis.
• docker_command: Docker command used to launch the container.
• docker_service_volume_name: Name of the docker volume for the service.
• db_type: mariadb (default), postgres or mongo.
• docker_service_directory_db: Path for the postgres/mongo db data.
• db_pass: Root password for the DB.
• db_user_pass: User password for the DB.
• db_config_port: Host port that will be binded for the DB setup.
• db_name: Name of the DB that will be created.
• db_user: Name of the user that will own the created DB.
• db_expose_port: Port to be exposed of the db.
• docker_service_directory_redis: Path for the Redis data.

Dependencies

None.

Example Playbook

- name: '[Pretask] Create directories'
  hosts: all
  vars:
    db_type: postgres
    docker_service_directory_db: /data/hello-world/db
  tasks:
    - name: Create db data directory
      file:
        path: "{{ docker_service_directory_db }}"
        state: directory
        owner: [user with uid 1000]
        group: [group with gid 1000]
        mode: 0700

- name: Deploy the docker image managed by a systemd service
  hosts: all
  vars:
    db_type: mariadb
    db_pass: 'changeme'
    db_user_pass: 'changeme'
    db_config_port: 3306
    db_name: hello-world
    db_user: hello-world
    service_name: hello-world
    docker_image: hello-world
    docker_command: /usr/bin/docker run --rm -i --name "{{ service_name }}" "{{ docker_image }}"
  roles:
    - role: generic_docker_systemd

If you are using postgres:

- name: '[Pretask] Create directories'
  hosts: all
  vars:
    db_type: postgres
    docker_service_directory_db: /data/hello-world/db
  tasks:
    - name: Create db data directory
      file:
        path: "{{ docker_service_directory_db }}"
        state: directory
        owner: [user with uid 1000]
        group: [group with gid 1000]
        mode: 0700

- name: Deploy the docker image managed by a systemd service
  hosts: all
  vars:
    db_type: postgres
    docker_db_image: postgres:11
    docker_service_directory_db: /data/hello-world/db
    db_user_pass: 'changeme'
    db_config_port: 5432
    db_name: hello-world
    db_user: hello-world
    service_name: hello-world
    docker_image: hello-world
    docker_command: /usr/bin/docker run --rm -i --name "{{ service_name }}" "{{ docker_image }}"
  roles:
    - role: generic_docker_systemd

If you are using mongo:

- name: '[Pretask] Create directories'
  hosts: all
  vars:
    db_type: mongo
    docker_service_directory_db: /data/hello-world/db
  tasks:
    - name: Create db data directory
      file:
        path: "{{ docker_service_directory_db }}"
        state: directory
        owner: [user with uid 1000]
        group: [group with gid 1000]
        mode: 0700

- name: Deploy the docker image managed by a systemd service
  hosts: all
  vars:
    db_type: mongo
    docker_db_image: mongo:4
    docker_service_directory_db: /data/hello-world/db
    db_user_pass: 'changeme'
    db_config_port: 27017
    db_name: hello-world
    db_user: hello-world
    service_name: hello-world
    docker_image: hello-world
    docker_command: /usr/bin/docker run --rm -i --name "{{ service_name }}" "{{ docker_image }}"
  roles:
    - role: generic_docker_systemd

Testing

To test the role you need molecule. And vagrant installed with VirtualBox.

There are too scenarios depending on the posible database backend, to test both of them use:

molecule test -s default
molecule test -s postgres
molecule test -s mongo

License

GPLv3

Author Information

m0wer: m0wer (at) autistici (dot) org