add prometheus role

roles/prometheus/molecule/default/converge.yml

@@ -0,0 +1,8 @@
+---
+- name: Converge
+  hosts: all
+
+  roles:
+    - role: genlab.prometheus
+      config_source_dir: prometheus
+      alertrules_source_dir: prometheus/rules

roles/prometheus/molecule/default/molecule.yml

@@ -0,0 +1,27 @@
+---
+dependency:
+  name: galaxy
+
+driver:
+  name: docker
+
+platforms:
+  - name: ubuntu
+    image: geerlingguy/docker-${MOLECULE_DISTRO:-ubuntu2404}-ansible:latest
+    pre_build_image: true
+    command: ${MOLECULE_DOCKER_COMMAND:-""}
+    volumes:
+      - /sys/fs/cgroup:/sys/fs/cgroup:rw
+    cgroupns_mode: host
+    privileged: true
+
+provisioner:
+  name: ansible
+
+verifier:
+  name: ansible
+
+lint: |
+  set -e
+  yamllint .
+  ansible-lint .

roles/prometheus/molecule/default/prometheus/prometheus.yml

@@ -0,0 +1,14 @@
+---
+global:
+  scrape_interval:     15s
+  evaluation_interval: 15s
+
+rule_files:
+  - /etc/prometheus/conf/alertules.yml
+  # - "first.rules"
+  # - "second.rules"
+
+scrape_configs:
+  - job_name: prometheus
+    static_configs:
+      - targets: ['localhost:9090']

roles/prometheus/molecule/default/prometheus/rules/alertrules.yml

@@ -0,0 +1,13 @@
+groups:
+- name: example
+  labels:
+    team: myteam
+  rules:
+  - alert: HighRequestLatency
+    expr: job:request_latency_seconds:mean5m{job="myjob"} > 0.5
+    for: 10m
+    keep_firing_for: 5m
+    labels:
+      severity: page
+    annotations:
+      summary: High request latency

roles/prometheus/molecule/default/verify.yml

@@ -0,0 +1,55 @@
+---
+- name: Verify
+  hosts: all
+  gather_facts: false
+  any_errors_fatal: true
+
+  tasks:
+
+    - name: "Include default vars"
+      ansible.builtin.include_vars:
+        dir: "{{ lookup('env', 'MOLECULE_PROJECT_DIRECTORY') }}/defaults/"
+        extensions: [ 'yml' ]
+
+    - name: "Check if Prometheus is installed"
+      changed_when: false
+      ansible.builtin.command: "prometheus --version"
+      register: prom_installed_version
+
+    - name: "Check Prometheus version"
+      ansible.builtin.assert:
+        that: "prom_installed_version.stdout is regex('{{ prometheus_version }}')"
+        success_msg: "Prometheus version {{ prometheus_version }} is installed and working"
+        fail_msg: "Prometheus version {{ prometheus_version }} is not installed or not working correctly"
+
+    # kics-scan ignore-block
+    - name: "Check if Prometheus is reachable"
+      ansible.builtin.uri:
+        url: "http://localhost:9090/-/healthy"
+        return_content: true
+        status_code: 200
+        method: GET
+        body_format: json
+      register: prom_health
+
+    - name: "Debug Prometheus health status"
+      ansible.builtin.assert:
+        that: "prom_health.content | trim == 'Prometheus Server is Healthy.'"
+        success_msg: "Prometheus is healthy"
+        fail_msg: "Prometheus is not healthy"
+
+    # kics-scan ignore-block
+    - name: "Check if Prometheus is ready"
+      ansible.builtin.uri:
+        url: "http://localhost:9090/-/ready"
+        return_content: true
+        status_code: 200
+        method: GET
+        body_format: json
+      register: prom_ready
+
+    - name: "Debug Prometheus readiness status"
+      ansible.builtin.assert:
+        that: "prom_ready.content | trim == 'Prometheus Server is Ready.'"
+        success_msg: "Prometheus is ready"
+        fail_msg: "Prometheus is not ready"