Merge pull request #69 from tyler-8/metricscfg

Add support for Netbox metrics configurations

Author: lae

README.adoc

@@ -305,6 +305,17 @@ netbox_webhooks_enabled: false
 
 Toggle `netbox_webhooks_enabled` to `true` to enable webhooks for NetBox.
 
+[source,yaml]
+netbox_metrics_enabled: true
+
+Toggle `netbox_metrics_enabled` to `true` to enable application metrics (via https://github.com/korfuri/django-prometheus[django-prometheus]). This adds relevant pieces of configuration for proper metrics handling. (https://netbox.readthedocs.io/en/stable/additional-features/prometheus-metrics/[more info]).
+
+[source,yaml]
+netbox_metrics_dir: netbox_metrics
+netbox_metrics_path: "/run/{{ netbox_metrics_dir }}"
+
+The directory name where the metrics files are stored can be set with `netbox_metrics_dir`. However, `netbox_metrics_path` must remain the default (seen above) in order to work with `systemd` and the `RuntimeDirectory` parameter (which only points to `/run`).
+
 [source,yaml]
 netbox_keep_uwsgi_updated: false
 

defaults/main.yml

@@ -32,6 +32,10 @@ netbox_redis_ssl_enabled: false
 
 netbox_webhooks_enabled: false
 
+netbox_metrics_enabled: false
+netbox_metrics_dir: netbox_metrics
+netbox_metrics_path: "/run/{{ netbox_metrics_dir }}"
+
 netbox_config:
   #SECRET_KEY:
   ALLOWED_HOSTS:

templates/configuration.py.j2

@@ -1,6 +1,18 @@
 import json
-
+import os
 {{ ansible_managed | comment }}
+
+{% if netbox_metrics_enabled %}
+if "prometheus_multiproc_dir" in os.environ:
+    try:
+        import prometheus_client
+        import uwsgi
+        prometheus_client.values.ValueClass = prometheus_client.values.MultiProcessValue(
+            _pidFunc=uwsgi.worker_id)
+    except ImportError:
+        pass  # not running in uwsgi
+{% endif %}
+
 DATABASE = {
     'NAME': '{{ netbox_database }}',
     'USER': '{{ netbox_database_user }}',
@@ -28,6 +40,10 @@ REDIS = {
 WEBHOOKS_ENABLED = True
 {% endif %}
 
+{% if netbox_metrics_enabled %}
+METRICS_ENABLED = True
+{% endif %}
+
 {% for setting, value in netbox_config.items() %}
 {% if value in [True, False] %}
 {{ setting }} = {{ 'True' if value else 'False' }}

templates/netbox.service.j2

@@ -31,6 +31,9 @@ DeviceAllow=/dev/urandom r
 DeviceAllow=/dev/zero r
 ProtectHome=yes
 NoNewPrivileges=yes
+{% if netbox_metrics_enabled %}
+RuntimeDirectory={{ netbox_metrics_dir }}
+{% endif %}
 
 [Install]
 WantedBy=multi-user.target

templates/uwsgi.ini.j2

@@ -16,8 +16,13 @@ chdir={{ netbox_current_path }}/netbox
 static-map=/{{ _base_path }}static={{ netbox_current_path }}/netbox/static
 logger={{ netbox_application_log }}
 req-logger={{ netbox_requests_log }}
+{% if netbox_metrics_enabled %}
+env=prometheus_multiproc_dir={{ netbox_metrics_path }}
+{% endif %}
 {% for key, value in netbox_uwsgi_options.items() %}
+{% if 'prometheus_multiproc_dir' not in value|string %}
 {{ key }}={{ value }}
+{% endif %}
 {% endfor %}
 
 # vim: ft=dosini

tests/group_vars/netbox

@@ -18,6 +18,7 @@ netbox_database_host: 10.0.3.1
 netbox_database_password:
 netbox_database_user: postgres
 netbox_webhooks_enabled: true
+netbox_metrics_enabled: true
 netbox_redis_host: 10.0.3.1
 netbox_uwsgi_options:
   buffer-size: 65535

tests/test.yml

@@ -25,3 +25,6 @@
     - name: Ensure that NetBox returns a successful HTTP response
       uri:
         url: "http://{{ inventory_hostname }}:8080"
+    - name: Check that Netbox metrics endpoint works
+      uri:
+        url: "http://{{ inventory_hostname }}:8080/metrics"