feat: create a variable for node exporter command

Users can override this list to customize collectors.
The TLS flag still prepends the --web.config.file entry when tls_cert_exists is true, so that behavior is unchanged.

Author: dudy-duce

roles/edpm_telemetry/defaults/main.yml

@@ -43,6 +43,27 @@ edpm_telemetry_image_download_retries: "{{ edpm_download_retries | default(5) }}
 # list of tripleo telemetry services to stop during EDPM adoption
 edpm_telemetry_old_tripleo_compute_sevices:
   - tripleo_ceilometer_agent_compute.service
+
+# Command options for node_exporter. This can be overridden to enable/disable collectors
+# Keep this as a list of strings which will be rendered into the container JSON command.
+edpm_telemetry_node_exporter_cmd:
+  - "--web.disable-exporter-metrics"
+  - "--collector.systemd"
+  - "--collector.systemd.unit-include=(edpm_.*|ovs.*|openvswitch|virt.*|rsyslog)\\.service"
+  - "--no-collector.dmi"
+  - "--no-collector.entropy"
+  - "--no-collector.thermal_zone"
+  - "--no-collector.time"
+  - "--no-collector.timex"
+  - "--no-collector.uname"
+  - "--no-collector.stat"
+  - "--no-collector.hwmon"
+  - "--no-collector.os"
+  - "--no-collector.selinux"
+  - "--no-collector.textfile"
+  - "--no-collector.powersupplyclass"
+  - "--no-collector.pressure"
+  - "--no-collector.rapl"
 # Instruction for distribution of container health check scripts
 edpm_telemetry_healthcheck_sources:
   ceilometer_agent_compute: ceilometer_agent

roles/edpm_telemetry/templates/node_exporter.json.j2

@@ -7,25 +7,11 @@
     "ports": ["9100:9100"],
     "command": [
 {% if tls_cert_exists|bool %}
-        "--web.config.file=/etc/node_exporter/node_exporter.yaml",
+    "--web.config.file=/etc/node_exporter/node_exporter.yaml",
 {% endif %}
-        "--web.disable-exporter-metrics",
-        "--collector.systemd",
-        "--collector.systemd.unit-include=(edpm_.*|ovs.*|openvswitch|virt.*|rsyslog)\\.service",
-        "--no-collector.dmi",
-        "--no-collector.entropy",
-        "--no-collector.thermal_zone",
-        "--no-collector.time",
-        "--no-collector.timex",
-        "--no-collector.uname",
-        "--no-collector.stat",
-        "--no-collector.hwmon",
-        "--no-collector.os",
-        "--no-collector.selinux",
-        "--no-collector.textfile",
-        "--no-collector.powersupplyclass",
-        "--no-collector.pressure",
-        "--no-collector.rapl"
+{% for arg in edpm_telemetry_node_exporter_cmd %}
+    {{ arg | to_json }}{% if not loop.last %},{% endif %}
+{% endfor %}
     ],
     "net": "host",
     "environment": {