prometheus: Collect metrics from rabbitmq

The rabbitmq_prometheus plugin is available in RabbitMQ 3.8.

https://www.rabbitmq.com/prometheus.html

Implements: blueprint rabbitmq-prometheus
Co-Authored-By: Mark Goddard <mark@stackhpc.com>
Change-Id: I4d69a93a6c70db8d40626042cdbe773747b238ae

ansible/group_vars/all.yml

@@ -430,6 +430,7 @@ prometheus_node_exporter_port: "9100"
 prometheus_mysqld_exporter_port: "9104"
 prometheus_haproxy_exporter_port: "9101"
 prometheus_memcached_exporter_port: "9150"
+prometheus_rabbitmq_exporter_port: "15692"
 # Default cadvisor port of 8080 already in use
 prometheus_cadvisor_port: "18080"
 
@@ -1077,6 +1078,7 @@ enable_prometheus_ceph_mgr_exporter: "no"
 enable_prometheus_openstack_exporter: "{{ enable_prometheus | bool }}"
 enable_prometheus_elasticsearch_exporter: "{{ enable_prometheus | bool and enable_elasticsearch | bool }}"
 enable_prometheus_blackbox_exporter: "{{ enable_prometheus | bool }}"
+enable_prometheus_rabbitmq_exporter: "{{ enable_prometheus | bool and enable_rabbitmq | bool }}"
 
 prometheus_alertmanager_user: "admin"
 prometheus_openstack_exporter_interval: "60s"

ansible/roles/prometheus/templates/prometheus.yml.j2

@@ -47,6 +47,15 @@ scrape_configs:
 {% endfor %}
 {% endif %}
 
+{% if enable_prometheus_rabbitmq_exporter | bool %}
+  - job_name: rabbitmq
+    static_configs:
+      - targets:
+{% for host in groups['rabbitmq'] %}
+        - '{{ 'api' | kolla_address(host) | put_address_in_context('url') }}:{{ hostvars[host]['prometheus_rabbitmq_exporter_port'] }}'
+{% endfor %}
+{% endif %}
+
 {% if enable_prometheus_memcached_exporter | bool %}
   - job_name: memcached
     static_configs:

releasenotes/notes/prometheus-rabbitmq-f7d6ebf0d611a819.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    Adds support for collecting Prometheus metrics from RabbitMQ. This is
+    enabled by default when Prometheus and RabbitMQ are enabled, and may be
+    disabled by setting ``enable_prometheus_rabbitmq_exporter`` to ``false``.