ansible-config/roles/prometheus/tasks/main.yml

---
- name: Create prometheus system user
  user:
    name: "{{ prometheus_user }}"
    shell: /bin/false
    home: /nonexistent
    create_home: no
    system: yes
    state: present

- name: Create prometheus directories
  file:
    path: "{{ item }}"
    state: directory
    owner: "{{ prometheus_user }}"
    group: "{{ prometheus_group }}"
    mode: '0755'
  loop:
    - "{{ prometheus_config_dir }}"
    - "{{ prometheus_config_dir }}/rules"
    - "{{ prometheus_config_dir }}/file_sd"
    - "{{ prometheus_data_dir }}"

- name: Check if Prometheus is already installed
  stat:
    path: "{{ prometheus_binary_dir }}/prometheus"
  register: prometheus_binary

- name: Check Prometheus version
  shell: "{{ prometheus_binary_dir }}/prometheus --version 2>&1 | head -1 | awk '{print $3}'"
  register: prometheus_installed_version
  when: prometheus_binary.stat.exists
  changed_when: false
  failed_when: false

- name: Download and install Prometheus
  block:
    - name: Download Prometheus {{ prometheus_version }}
      unarchive:
        src: "https://github.com/prometheus/prometheus/releases/download/v{{ prometheus_version }}/prometheus-{{ prometheus_version }}.linux-amd64.tar.gz"
        dest: /tmp
        remote_src: yes
        owner: root
        group: root
        mode: '0755'

    - name: Copy Prometheus binaries
      copy:
        src: "/tmp/prometheus-{{ prometheus_version }}.linux-amd64/{{ item }}"
        dest: "{{ prometheus_binary_dir }}/{{ item }}"
        owner: root
        group: root
        mode: '0755'
        remote_src: yes
      loop:
        - prometheus
        - promtool
      notify: restart prometheus

    - name: Copy console libraries
      copy:
        src: "/tmp/prometheus-{{ prometheus_version }}.linux-amd64/{{ item }}/"
        dest: "{{ prometheus_config_dir }}/{{ item }}/"
        owner: "{{ prometheus_user }}"
        group: "{{ prometheus_group }}"
        remote_src: yes
      loop:
        - consoles
        - console_libraries

    - name: Clean up downloaded files
      file:
        path: "/tmp/prometheus-{{ prometheus_version }}.linux-amd64"
        state: absent
  when: not prometheus_binary.stat.exists or (prometheus_installed_version.stdout != prometheus_version)

- name: Configure Prometheus
  template:
    src: prometheus.yml.j2
    dest: "{{ prometheus_config_dir }}/prometheus.yml"
    owner: "{{ prometheus_user }}"
    group: "{{ prometheus_group }}"
    mode: '0644'
    backup: yes
    validate: "{{ prometheus_binary_dir }}/promtool check config %s"
  notify: reload prometheus

- name: Create Prometheus systemd service
  template:
    src: prometheus.service.j2
    dest: /etc/systemd/system/prometheus.service
    mode: '0644'
  notify: restart prometheus

- name: Ensure Prometheus is started and enabled
  systemd:
    name: prometheus
    state: started
    enabled: yes
    daemon_reload: yes

- name: Wait for Prometheus to be ready
  uri:
    url: "http://localhost:{{ prometheus_port }}/metrics"
    status_code: 200
  register: prometheus_health
  until: prometheus_health.status == 200
  retries: 10
  delay: 5

- name: Check Prometheus targets status
  uri:
    url: "http://localhost:{{ prometheus_port }}/api/v1/targets"
  register: targets_response

- name: Display Prometheus status
  debug:
    msg:
      - "Prometheus version: {{ prometheus_version }}"
      - "Prometheus URL: http://{{ ansible_host }}:{{ prometheus_port }}"
      - "Active targets: {{ targets_response.json.data.activeTargets | length }}"