Add collectd support to telegraf container

Telegraf can collect sample from collectd via UDP.
Configure collectd to exposed samples and telegraf to collect them.

Change-Id: Ie868a4c23cb793e6054e14ee1209a56256c130ac
Depends-On: I33b1a3fe606bf5bd4a08901c7bf274aed5303055

ansible/group_vars/all.yml

@@ -137,6 +137,8 @@ congress_api_port: "1789"
 
 cloudkitty_api_port: "8889"
 
+collectd_udp_port: "25826"
+
 designate_api_port: "9001"
 designate_bind_port: "53"
 designate_mdns_port: "5354"

ansible/roles/collectd/templates/collectd.conf.j2

@@ -4,3 +4,8 @@ LoadPlugin cpu
 LoadPlugin interface
 LoadPlugin load
 LoadPlugin memory
+LoadPlugin network
+
+<Plugin "network">
+    Server "{{ hostvars[inventory_hostname]['ansible_' + api_interface]['ipv4']['address'] }}" "{{ collectd_udp_port }}"
+</Plugin>

ansible/roles/telegraf/templates/telegraf.conf.j2

@@ -21,6 +21,13 @@
   percpu = true
   totalcpu = true
   fielddrop = ["time_*"]
+{% if enable_collectd | bool and inventory_hostname in groups['collectd'] %}
+[[inputs.socket_listener]]
+  service_address = "udp://{{ hostvars[inventory_hostname]['ansible_' + api_interface]['ipv4']['address'] }}:{{ collectd_udp_port }}"
+  name_prefix = "collectd_"
+  data_format = "collectd"
+  collectd_typesdb = ["/usr/share/collectd/types.db"]
+{% endif %}
 [[inputs.disk]]
   ignore_fs = ["tmpfs", "devtmpfs"]
 [[inputs.diskio]]