olimp/roles/docker/tasks/main.yml

---
# =============================================================================
# DOCKER ROLE - tasks/main.yml
# =============================================================================

# ========== Fix runc BEFORE Docker install (LXC safety) ==========
- name: Ensure runc at safe version before Docker install (LXC only)
  apt:
    name: "runc=1.1.12-0ubuntu3"
    state: present
    allow_downgrade: yes
    allow_change_held_packages: yes
  become: yes
  tags: [docker, deploy_docker]
  when: ansible_virtualization_type in ['lxc', 'container']

# ========== Install Docker ==========
- name: Install Docker dependencies
  apt:
    name:
      - apt-transport-https
      - ca-certificates
      - curl
      - gnupg
      - lsb-release
    state: present
    update_cache: yes
  become: yes
  tags: [docker, deploy_docker]

- name: Add Docker GPG key
  apt_key:
    url: https://download.docker.com/linux/ubuntu/gpg
    state: present
  become: yes
  tags: [docker, deploy_docker]

- name: Add Docker repository
  apt_repository:
    repo: "deb [arch=amd64] https://download.docker.com/linux/ubuntu {{ ansible_distribution_release }} stable"
    state: present
    update_cache: yes
  become: yes
  tags: [docker, deploy_docker]

- name: Install Docker packages
  apt:
    name:
      - docker-ce
      - docker-ce-cli
      - containerd.io
    state: present
    update_cache: yes
    allow_downgrade: yes
    allow_change_held_packages: yes
  become: yes
  notify: restart docker
  tags: [docker, deploy_docker]

- name: Install Docker Compose plugin
  apt:
    name: docker-compose-plugin
    state: present
  become: yes
  tags: [docker, deploy_docker]

- name: Start and enable Docker service
  systemd:
    name: docker
    state: started
    enabled: yes
    daemon_reload: yes
  become: yes
  tags: [docker, deploy_docker]

- name: Wait for Docker to start
  pause:
    seconds: 5
  tags: [docker, deploy_docker]

- name: Verify Docker installation
  command: docker --version
  register: docker_version
  changed_when: false
  tags: [docker, deploy_docker]

- name: Show Docker version
  debug:
    msg: "Docker version: {{ docker_version.stdout }}"
  tags: [docker, deploy_docker]

- name: Verify Docker Compose installation
  command: docker compose version
  register: docker_compose_version
  changed_when: false
  tags: [docker, deploy_docker]

- name: Show Docker Compose version
  debug:
    msg: "Docker Compose version: {{ docker_compose_version.stdout }}"
  tags: [docker, deploy_docker]

# ========== Docker Monitoring Setup ==========
- name: Setup Docker monitoring
  block:
    - name: Create scripts directory
      file:
        path: /opt/scripts
        state: directory
        mode: '0755'
      become: yes

    - name: Deploy Docker metrics script
      copy:
        content: |
          #!/bin/bash
          # Docker metrics script for Node Exporter textfile collector
          
          OUTFILE="/var/lib/node_exporter/textfile_collector/docker_metrics.prom"
          
          # Get container counts
          TOTAL_CONTAINERS=$(docker ps -a -q 2>/dev/null | wc -l)
          RUNNING_CONTAINERS=$(docker ps -q 2>/dev/null | wc -l)
          EXITED_CONTAINERS=$((TOTAL_CONTAINERS - RUNNING_CONTAINERS))
          
          # Write metrics in Prometheus format
          cat << EOF > $OUTFILE
          # HELP docker_containers_total Total number of Docker containers
          # TYPE docker_containers_total gauge
          docker_containers_total $TOTAL_CONTAINERS
          # HELP docker_containers_running Number of running Docker containers  
          # TYPE docker_containers_running gauge
          docker_containers_running $RUNNING_CONTAINERS
          # HELP docker_containers_exited Number of exited Docker containers
          # TYPE docker_containers_exited gauge
          docker_containers_exited $EXITED_CONTAINERS
          EOF          
        dest: /opt/scripts/docker_metrics.sh
        mode: '0755'
      become: yes

    - name: Create systemd service for Docker metrics
      copy:
        content: |
          [Unit]
          Description=Docker metrics script
          After=docker.service
          
          [Service]
          User=root
          ExecStart=/opt/scripts/docker_metrics.sh          
        dest: /etc/systemd/system/docker-metrics.service
        mode: '0644'
      become: yes

    - name: Create systemd timer for Docker metrics
      copy:
        content: |
          [Unit]
          Description=Run Docker metrics every 30 seconds
          
          [Timer]
          OnBootSec=1min
          OnUnitActiveSec=30s
          
          [Install]
          WantedBy=timers.target          
        dest: /etc/systemd/system/docker-metrics.timer
        mode: '0644'
      become: yes

    - name: Ensure Node Exporter textfile directory exists
      file:
        path: /var/lib/node_exporter/textfile_collector
        state: directory
        owner: node_exporter
        group: node_exporter
        mode: '0755'
      become: yes

    - name: Enable and start Docker metrics timer
      systemd:
        name: docker-metrics.timer
        enabled: yes
        state: started
        daemon_reload: yes
      become: yes

    - name: Test Docker metrics script
      command: /opt/scripts/docker_metrics.sh
      register: metrics_test
      changed_when: false

    - name: Show Docker metrics test result
      debug:
        var: metrics_test.stdout
  tags: [docker, deploy_docker, monitoring]

# ========== Optional: Manual runc update for non-LXC hosts ==========
- name: Check current runc version (non-LXC only)
  command: runc --version
  register: runc_version_check
  ignore_errors: yes
  changed_when: false
  become: yes
  when: ansible_virtualization_type not in ['lxc', 'container']
  tags: [docker, runc_update]

- name: Update runc to v1.2.4 if needed (non-LXC only)
  block:
    - name: Download runc v1.2.4
      get_url:
        url: https://github.com/opencontainers/runc/releases/download/v1.2.4/runc.amd64
        dest: /tmp/runc.amd64
        mode: '0755'
      become: yes

    - name: Stop docker service
      systemd:
        name: docker
        state: stopped
      become: yes

    - name: Backup existing runc
      command: mv /usr/bin/runc /usr/bin/runc.bak
      args:
        creates: /usr/bin/runc.bak
      become: yes

    - name: Install new runc
      copy:
        src: /tmp/runc.amd64
        dest: /usr/bin/runc
        remote_src: yes
        mode: '0755'
      become: yes

    - name: Start docker service
      systemd:
        name: docker
        state: started
      become: yes

    - name: Clean up temporary runc file
      file:
        path: /tmp/runc.amd64
        state: absent
      become: yes

    - name: Verify new runc version
      command: runc --version
      register: new_runc_version
      become: yes

    - name: Show runc update result
      debug:
        msg: "runc updated to version: {{ new_runc_version.stdout }}"
      become: yes
  when: 
    - ansible_virtualization_type not in ['lxc', 'container']
    - runc_version_check is failed or "'1.2.4' not in runc_version_check.stdout"
    - ansible_architecture == "x86_64"
  become: yes
  tags: [docker, runc_update]