chore: Configurable prometheus system user, group (#307)

Signed-off-by: Mahendra Paipuri <mahendra.paipuri@gmail.com>

roles/prometheus/defaults/main.yml

@@ -227,4 +227,7 @@ prometheus_alert_rules:  # noqa yaml[line-length]  # noqa line-length
       severity: warning
 # yamllint enable rule:line-length
 
+prometheus_system_group: 'prometheus'
+prometheus_system_user: "{{ prometheus_system_group }}"
+
 prometheus_stop_timeout: '600s'

roles/prometheus/meta/argument_specs.yml

@@ -150,6 +150,16 @@ argument_specs:
         default:
           - "prometheus/targets/*.yml"
           - "prometheus/targets/*.json"
+      prometheus_system_group:
+        description:
+          - "System group for Prometheus."
+        type: "str"
+        default: "prometheus"
+      prometheus_system_user:
+        description:
+          - "System user for Prometheus."
+        type: "str"
+        default: "prometheus"
       prometheus_stop_timeout:
         description:
           - "How long to wait for Prometheus to shutdown. This is passed as a systemd TimeoutStopSec time spec."

roles/prometheus/tasks/configure.yml

@@ -4,7 +4,7 @@
     src: "alert.rules.j2"
     dest: "{{ prometheus_config_dir }}/rules/ansible_managed.rules"
     owner: root
-    group: prometheus
+    group: "{{ prometheus_system_group }}"
     mode: 0640
     validate: "{{ _prometheus_binary_install_dir }}/promtool check rules %s"
   when:
@@ -18,7 +18,7 @@
     src: "{{ item }}"
     dest: "{{ prometheus_config_dir }}/rules/"
     owner: root
-    group: prometheus
+    group: "{{ prometheus_system_group }}"
     mode: 0640
     validate: "{{ _prometheus_binary_install_dir }}/promtool check rules %s"
   with_fileglob: "{{ prometheus_alert_rules_files }}"
@@ -33,7 +33,7 @@
     dest: "{{ prometheus_config_dir }}/prometheus.yml"
     force: true
     owner: root
-    group: prometheus
+    group: "{{ prometheus_system_group }}"
     mode: 0640
     validate: "{{ _prometheus_binary_install_dir }}/promtool check config %s"
   no_log: "{{ false if (lookup('env', 'CI')) or (lookup('env', 'MOLECULE_PROVISIONER_NAME')) else true }}"
@@ -46,7 +46,7 @@
     dest: "{{ prometheus_config_dir }}/web.yml"
     force: true
     owner: root
-    group: prometheus
+    group: "{{ prometheus_system_group }}"
     mode: 0640
 
 - name: Configure prometheus static targets
@@ -56,7 +56,7 @@
     dest: "{{ prometheus_config_dir }}/file_sd/{{ item.key }}.yml"
     force: true
     owner: root
-    group: prometheus
+    group: "{{ prometheus_system_group }}"
     mode: 0640
   with_dict: "{{ prometheus_targets }}"
   when: prometheus_targets != {}
@@ -67,6 +67,6 @@
     dest: "{{ prometheus_config_dir }}/file_sd/"
     force: true
     owner: root
-    group: prometheus
+    group: "{{ prometheus_system_group }}"
     mode: 0640
   with_fileglob: "{{ prometheus_static_targets_files }}"

roles/prometheus/tasks/install.yml

@@ -1,16 +1,16 @@
 ---
 - name: Create prometheus system group
   ansible.builtin.group:
-    name: prometheus
+    name: "{{ prometheus_system_group }}"
     system: true
     state: present
 
 - name: Create prometheus system user
   ansible.builtin.user:
-    name: prometheus
+    name: "{{ prometheus_system_user }}"
     system: true
     shell: "/usr/sbin/nologin"
-    group: prometheus
+    group: "{{ prometheus_system_group }}"
     createhome: false
     home: "{{ prometheus_db_dir }}"
 
@@ -18,8 +18,8 @@
   ansible.builtin.file:
     path: "{{ prometheus_db_dir }}"
     state: directory
-    owner: prometheus
-    group: prometheus
+    owner: "{{ prometheus_system_user }}"
+    group: "{{ prometheus_system_group }}"
     mode: 0755
 
 - name: Create prometheus configuration directories
@@ -27,7 +27,7 @@
     path: "{{ item }}"
     state: directory
     owner: root
-    group: prometheus
+    group: "{{ prometheus_system_group }}"
     mode: 0770
   with_items:
     - "{{ prometheus_config_dir }}"

roles/prometheus/templates/prometheus.service.j2

@@ -9,8 +9,8 @@ After=local-fs.target
 [Service]
 Type=simple
 Environment="GOMAXPROCS={{ ansible_processor_vcpus|default(ansible_processor_count) }}"
-User=prometheus
-Group=prometheus
+User={{ prometheus_system_user }}
+Group={{ prometheus_system_group }}
 ExecReload=/bin/kill -HUP $MAINPID
 ExecStart={{ _prometheus_binary_install_dir }}/prometheus \
 {% if not prometheus_agent_mode %}