---
- name: 部署Node Exporter
  hosts: "{{ target_hosts | default('all') }}"
  become: yes
  vars:
    exporter_version: "1.7.0"
    exporter_port: 9100

  tasks:
    - name: 创建用户
      user:
        name: node_exporter
        system: yes
        shell: /usr/sbin/nologin
        create_home: no

    - name: 下载Node Exporter
      get_url:
        url: "https://github.com/prometheus/node_exporter/releases/download/v{{ exporter_version }}/node_exporter-{{ exporter_version }}.linux-amd64.tar.gz"
        dest: /tmp/node_exporter.tar.gz

    - name: 解压
      unarchive:
        src: /tmp/node_exporter.tar.gz
        dest: /tmp
        remote_src: yes

    - name: 安装二进制
      copy:
        src: "/tmp/node_exporter-{{ exporter_version }}.linux-amd64/node_exporter"
        dest: /usr/local/bin/node_exporter
        mode: '0755'
        remote_src: yes

    - name: 创建Systemd服务
      copy:
        content: |
          [Unit]
          Description=Node Exporter
          After=network.target

          [Service]
          User=node_exporter
          ExecStart=/usr/local/bin/node_exporter --web.listen-address=:{{ exporter_port }}
          Restart=always

          [Install]
          WantedBy=multi-user.target
        dest: /etc/systemd/system/node_exporter.service

    - name: 启动服务
      systemd:
        name: node_exporter
        state: started
        enabled: yes
        daemon_reload: yes

    - name: 验证
      shell: curl -s http://localhost:{{ exporter_port }}/metrics | head -5
      register: metrics
      changed_when: false

    - name: 显示状态
      debug:
        msg: "Node Exporter运行在端口 {{ exporter_port }}"