---
- name: Install prometheus
  apt:
    name:
      - prometheus

- name: Configure prometheus
  template:
    src: prometheus.yml.j2
    dest: /etc/prometheus/prometheus.yml
    owner: prometheus
    group: prometheus
    mode: u=rw,g=r,o=r
  vars:
    prometheus__config:
      alerting:
        alertmanagers:
          - static_configs:
              - targets: "{{ prometheus__alertmanager_targets }}"
      rule_files:
        - /etc/prometheus/rules.yml
      scrape_configs: "{{ prometheus__scraping
                          | prometheus__convert_jobs }}"
  notify:
    - Restart prometheus

- name: Configure prometheus default
  template:
    src: default.j2
    dest: /etc/default/prometheus
    owner: root
    group: root
    mode: u=rw,g=r,o=r
  notify:
    - Restart prometheus

- name: Configure prometheus rules
  template:
    src: rules.yml.j2
    dest: /etc/prometheus/rules.yml
    owner: prometheus
    group: prometheus
    mode: u=rw,g=r,o=r
    validate: "promtool check rules %s"
  vars:
    prometheus__rules:
      groups: "{{ prometheus__alert_rules
                  | dict2items(key_name='name', value_name='rules') }}"
  notify:
    - Reload prometheus

- name: Enable prometheus
  systemd:
    name: prometheus
    enabled: true
    state: started
...