enable setting expiration_interval in prometheus client
For some metrics with high inertia (like Openstack)
expiration interval prevents appearing of data gaps.
PROD-18242
Change-Id: I7939db8f32a1abf6ab8bde0166858c43ca178d3c
diff --git a/telegraf/files/output/prometheus_client.conf b/telegraf/files/output/prometheus_client.conf
index 6677bc2..b60f26a 100644
--- a/telegraf/files/output/prometheus_client.conf
+++ b/telegraf/files/output/prometheus_client.conf
@@ -1,4 +1,7 @@
[[outputs.{{ name }}]]
{%- if values is defined %}
listen = "{{ values.bind.address }}:{{ values.bind.port }}"
+{%- if values.expiration_interval is defined %}
+expiration_interval = "{{ values.expiration_interval }}"
+{%- endif %}
{%- endif %}