docker-swarm.yml

---
- hosts: docker-nodes
  become: true
  vars:
    docker_swarm_addr: "{{ hostvars[inventory_hostname]['ansible_' + docker_swarm_interface]['ipv4']['address'] }}"
    docker_swarm_cert_expiry: '2160h0m0s' # Validity period for node certificates (default 2160h0m0s)
    docker_swarm_dispatcher_heartbeat_duration: '5s' # Dispatcher heartbeat period (default 5s)
    docker_swarm_interface: "enp0s8"
    # docker_swarm_managers_ansible_group: 'docker-swarm-managers'
    docker_swarm_networks:
      - name: 'my_net'
        driver: 'overlay'
        state: 'present'
      - name: 'test'
        driver: 'overlay'
        state: 'absent'
    docker_swarm_primary_manager: '{{ groups[docker_swarm_managers_ansible_group][0] }}'
    # docker_swarm_primary_manager: 'node0'
    docker_swarm_task_history_limit: '5' # Task history retention limit (default 5)
    # docker_swarm_workers_ansible_group: 'docker-swarm-workers'
    docker_swarm_port: "2377"
  tasks:
    - name: docker_swarm | Installing EPEL Repo (RedHat)
      yum:
        name: "epel-release"
        state: "present"
      when: >
            ansible_os_family == "RedHat" and
            ansible_distribution != "Fedora"

    - name: docker_swarm | Installing Pre-Reqs
      apt:
        name: "python-pip"
        state: "present"
      when: ansible_os_family == "Debian"

## Installing these for future functionality
    - name: docker_swarm | Installing Python Pre-Reqs
      pip:
        name: "{{ item }}"
        state: "present"
      with_items:
        - 'docker-py'
##

    - name: docker_swarm | Ensuring Docker Engine Is Running
      service:
        name: "docker"
        state: "started"

    - name: docker_swarm | Checking Swarm Mode Status
      command: "docker info"
      register: "docker_info"
      changed_when: false

    - name: docker_swarm | Init Docker Swarm Mode On First Manager
      command: >
              docker swarm init
              --listen-addr {{ docker_swarm_addr }}:{{ docker_swarm_port }}
              --advertise-addr {{ docker_swarm_addr }}
      when: >
            'Swarm: inactive' in docker_info.stdout and
            inventory_hostname == docker_swarm_primary_manager

    - name: docker_swarm | Capturing Docker Swarm Worker join-token
      command: "docker swarm join-token -q worker"
      changed_when: false
      register: "docker_swarm_worker_token"
      when: >
            inventory_hostname == docker_swarm_primary_manager

    - name: docker_swarm | Capturing Docker Swarm Manager join-token
      command: "docker swarm join-token -q manager"
      changed_when: false
      register: "docker_swarm_manager_token"
      when: >
            inventory_hostname == docker_swarm_primary_manager

    - name: docker_swarm | Defining Docker Swarm Manager Address
      set_fact:
        docker_swarm_manager_address: "{{ docker_swarm_addr }}:{{ docker_swarm_port }}"
      changed_when: false
      when: >
            inventory_hostname == docker_swarm_primary_manager

    - name: docker_swarm | Defining Docker Swarm Manager Address
      set_fact:
        docker_swarm_manager_address: "{{ hostvars[docker_swarm_primary_manager]['docker_swarm_manager_address'] }}"
      changed_when: false
      when: >
            inventory_hostname != docker_swarm_primary_manager

    - name: docker_swarm | Defining Docker Swarm Manager join-token
      set_fact:
        docker_swarm_manager_token: "{{ hostvars[docker_swarm_primary_manager]['docker_swarm_manager_token'] }}"
      changed_when: false
      when: >
            inventory_hostname != docker_swarm_primary_manager

    - name: docker_swarm | Defining Docker Swarm Worker join-token
      set_fact:
        docker_swarm_worker_token: "{{ hostvars[docker_swarm_primary_manager]['docker_swarm_worker_token'] }}"
      changed_when: false
      when: >
            inventory_hostname != docker_swarm_primary_manager

    - name: docker_swarm | Joining Additional Docker Swarm Managers To Cluster
      command: >
              docker swarm join
              --listen-addr {{ docker_swarm_addr }}:{{ docker_swarm_port }}
              --advertise-addr {{ docker_swarm_addr }}
              --token {{ docker_swarm_manager_token.stdout }}
              {{ docker_swarm_manager_address }}
      when: >
            inventory_hostname != docker_swarm_primary_manager and
            inventory_hostname not in groups[docker_swarm_workers_ansible_group] and
            'Swarm: active' not in docker_info.stdout and
            'Swarm: pending' not in docker_info.stdout

    - name: docker_swarm | Joining Docker Swarm Workers To Cluster
      command: >
             docker swarm join
             --listen-addr {{ docker_swarm_addr }}:{{ docker_swarm_port }}
             --advertise-addr {{ docker_swarm_addr }}
             --token {{ docker_swarm_worker_token.stdout }}
             {{ docker_swarm_manager_address }}
      when: >
            inventory_hostname in groups[docker_swarm_workers_ansible_group] and
            'Swarm: active' not in docker_info.stdout and
            'Swarm: pending' not in docker_info.stdout

    - name: docker_swarm | Capturing Docker Swarm Networks
      command: "docker network ls"
      changed_when: false
      register: "docker_networks"
      when: >
            inventory_hostname == docker_swarm_primary_manager

    - name: docker_swarm | Creating Docker Swarm Networks
      command: "docker network create --driver {{ item.driver }} {{ item.name }}"
      with_items: '{{ docker_swarm_networks }}'
      when: >
            inventory_hostname == docker_swarm_primary_manager and
            item.state|lower == "present" and
            item.name not in docker_networks.stdout

    - name: docker_swarm | Removing Docker Swarm Networks
      command: "docker network rm {{ item.name }}"
      with_items: '{{ docker_swarm_networks }}'
      when: >
            inventory_hostname == docker_swarm_primary_manager and
            item.state|lower == "absent" and
            item.name in docker_networks.stdout

## Below is for Ansible 2.2
    # - name: docker_swarm | Managing Docker Swarm Networks
    #   docker_network:
    #     name: "{{ item.name }}"
    #     driver: "{{ item.driver }}"
    #     state: "{{ item.state }}"
    #   with_items: '{{ docker_swarm_networks }}'
    #   when: >
    #         inventory_hostname == docker_swarm_primary_manager

    - name: docker_swarm | Updating Docker Swarm Dispatch Heartbeat Duration
      command: "docker swarm update --dispatcher-heartbeat {{ docker_swarm_dispatcher_heartbeat_duration }}"
      when: >
            inventory_hostname == docker_swarm_primary_manager

    - name: docker_swarm | Updating Docker Swarm Certificate Expiry Duration
      command: "docker swarm update --cert-expiry {{ docker_swarm_cert_expiry }}"
      when: >
            inventory_hostname == docker_swarm_primary_manager

    - name: docker_swarm | Updating Docker Swarm Task History Limit
      command: "docker swarm update --task-history-limit {{ docker_swarm_task_history_limit }}"
      when: >
            inventory_hostname == docker_swarm_primary_manager