homelab/ansible/archive/playbooks/ai/deploy_ansible_mcp_watchtower.yml

---
# Deploy a custom Ansible MCP server on Watchtower.
#
# Usage:
#   cd /home/chester/homelab/ansible
#   ansible-playbook -i inventory/hosts.ini playbooks/ai/deploy_ansible_mcp_watchtower.yml
#
# Validate only:
#   ansible-playbook -i inventory/hosts.ini playbooks/ai/deploy_ansible_mcp_watchtower.yml --check

- name: Deploy Ansible MCP server on Watchtower
  hosts: watchtower
  become: true
  gather_facts: true

  vars:
    mcp_service_name: ansible-mcp
    mcp_install_dir: /opt/ansible-mcp
    mcp_state_dir: /var/lib/ansible-mcp
    mcp_user: chester
    mcp_group: chester
    mcp_transport: streamable-http
    mcp_host: 0.0.0.0
    mcp_port: 8449

    mcp_repo_root: /home/chester/homelab/ansible
    mcp_inventory: inventory/hosts.ini
    mcp_allowed_playbook_dirs: playbooks
    mcp_allowed_playbooks: ""
    mcp_api_token: "{{ lookup('env', 'ANSIBLE_MCP_API_TOKEN') | default('', true) }}"
    mcp_max_extra_vars_bytes: 16384
    mcp_blocked_extra_vars_keys: "ansible_password,ansible_become_password,vault_password"

    # Full-write mode is enabled by default here to match requested behavior.
    # Keep confirm enforcement enabled in server guardrails.
    mcp_allow_write: true
    mcp_require_confirm_for_write: true

    mcp_default_timeout: 900
    mcp_max_timeout: 3600

    mcp_python_packages:
      - ansible-core>=2.16,<2.19
      - mcp>=1.0.0

  tasks:
    - name: Assert API token is configured for HTTP transport
      ansible.builtin.assert:
        that:
          - mcp_transport == "stdio" or (mcp_api_token | length) > 0
        fail_msg: >-
          HTTP transport requires ANSIBLE_MCP_API_TOKEN to be set in the control
          shell environment before running this playbook.
        success_msg: "Transport/auth configuration validated."

    - name: Assert service account exists
      ansible.builtin.getent:
        database: passwd
        key: "{{ mcp_user }}"

    - name: Ensure installation and state directories exist
      ansible.builtin.file:
        path: "{{ item.path }}"
        state: directory
        owner: "{{ item.owner }}"
        group: "{{ item.group }}"
        mode: "{{ item.mode }}"
      loop:
        - { path: "{{ mcp_install_dir }}", owner: "{{ mcp_user }}", group: "{{ mcp_group }}", mode: "0755" }
        - { path: "{{ mcp_state_dir }}", owner: "{{ mcp_user }}", group: "{{ mcp_group }}", mode: "0750" }

    - name: Copy MCP server script
      ansible.builtin.copy:
        src: ../../scripts/ansible_mcp_server.py
        dest: "{{ mcp_install_dir }}/ansible_mcp_server.py"
        owner: "{{ mcp_user }}"
        group: "{{ mcp_group }}"
        mode: "0755"
      notify: Restart ansible mcp service

    - name: Ensure Python venv exists
      ansible.builtin.command: "python3 -m venv {{ mcp_install_dir }}/.venv"
      args:
        creates: "{{ mcp_install_dir }}/.venv/bin/python"
      changed_when: false

    - name: Install MCP server dependencies in venv
      ansible.builtin.pip:
        name: "{{ mcp_python_packages }}"
        virtualenv: "{{ mcp_install_dir }}/.venv"
        state: present
      notify: Restart ansible mcp service

    - name: Install systemd unit for ansible mcp service
      ansible.builtin.copy:
        dest: "/etc/systemd/system/{{ mcp_service_name }}.service"
        owner: root
        group: root
        mode: "0644"
        content: |
          [Unit]
          Description=Ansible MCP Server
          Wants=network-online.target
          After=network-online.target

          [Service]
          Type=simple
          User={{ mcp_user }}
          Group={{ mcp_group }}
          WorkingDirectory={{ mcp_repo_root }}
          Environment=ANSIBLE_MCP_REPO_ROOT={{ mcp_repo_root }}
          Environment=ANSIBLE_MCP_INVENTORY={{ mcp_inventory }}
          Environment=ANSIBLE_MCP_ALLOWED_PLAYBOOK_DIRS={{ mcp_allowed_playbook_dirs }}
          Environment=ANSIBLE_MCP_ALLOWED_PLAYBOOKS={{ mcp_allowed_playbooks }}
          Environment=ANSIBLE_MCP_API_TOKEN={{ mcp_api_token }}
          Environment=ANSIBLE_MCP_ALLOW_WRITE={{ mcp_allow_write | ternary('true', 'false') }}
          Environment=ANSIBLE_MCP_REQUIRE_CONFIRM={{ mcp_require_confirm_for_write | ternary('true', 'false') }}
          Environment=ANSIBLE_MCP_DEFAULT_TIMEOUT={{ mcp_default_timeout }}
          Environment=ANSIBLE_MCP_MAX_TIMEOUT={{ mcp_max_timeout }}
          Environment=ANSIBLE_MCP_MAX_EXTRA_VARS_BYTES={{ mcp_max_extra_vars_bytes }}
          Environment=ANSIBLE_MCP_BLOCKED_EXTRA_VARS_KEYS={{ mcp_blocked_extra_vars_keys }}
          Environment=ANSIBLE_MCP_STATE_DIR={{ mcp_state_dir }}
          Environment=ANSIBLE_MCP_TRANSPORT={{ mcp_transport }}
          Environment=ANSIBLE_MCP_HOST={{ mcp_host }}
          Environment=ANSIBLE_MCP_PORT={{ mcp_port }}
          ExecStart={{ mcp_install_dir }}/.venv/bin/python {{ mcp_install_dir }}/ansible_mcp_server.py --transport {{ mcp_transport }} --host {{ mcp_host }} --port {{ mcp_port }}
          Restart=on-failure
          RestartSec=3

          [Install]
          WantedBy=multi-user.target
      notify:
        - Reload systemd
        - Restart ansible mcp service

    - name: Ensure ansible mcp service is enabled and running
      ansible.builtin.systemd:
        name: "{{ mcp_service_name }}"
        enabled: true
        state: started

    - name: Verify MCP health endpoint
      ansible.builtin.uri:
        url: "http://127.0.0.1:{{ mcp_port }}"
        method: GET
        return_content: true
        status_code: 200
      changed_when: false
      register: _mcp_http_probe
      failed_when: false

    - name: Show deployment summary
      ansible.builtin.debug:
        msg:
          - "Ansible MCP deployed to watchtower"
          - "Service: {{ mcp_service_name }}"
          - "Transport: {{ mcp_transport }}"
          - "Endpoint: {{ mcp_host }}:{{ mcp_port }}"
          - "Repo root: {{ mcp_repo_root }}"
          - "Allow write: {{ mcp_allow_write }}"
          - "Auth enabled: {{ (mcp_api_token | length) > 0 }}"
          - "Require confirm for write: {{ mcp_require_confirm_for_write }}"
          - "Explicit playbook allowlist set: {{ (mcp_allowed_playbooks | length) > 0 }}"
          - "HTTP probe status: {{ _mcp_http_probe.status | default('n/a') }}"

  handlers:
    - name: Reload systemd
      ansible.builtin.systemd:
        daemon_reload: true

    - name: Restart ansible mcp service
      ansible.builtin.systemd:
        name: "{{ mcp_service_name }}"
        state: restarted